NOTE: This document is exported from a MS Word document that contains complex formatting and images, including mathematical expressions. These are not reproduced in this plain text file. Formulas are not valid in this text file as they contain non-ASCII characters that have been removed per PDS standards. We strongly recommend using the original EPPS_DDR_SIS.DOCX or PDF version of this document (EPPS_DDR_SIS.PDF) included in the same directory in the archive volume. MESSENGER: Software Interface Specification for the Derived Data Records of the Energetic Particle and Plasma Spectrometer Version 2C Prepared by George Ho, Lawrence Brown, Lillian Nguyen, Michele Gannon, and Michael Reid Johns Hopkins University Applied Physics Laboratory Jim Raines University of Michigan Document Review This document and the archive it describes have been through PDS Peer Review and have been accepted into the PDS archive. George Ho, MESSENGER EPPS Instrument Scientist, has reviewed and approved this document. Jim Raines, MESSENGER FIPS Instrument Scientist, has reviewed and approved this document. Susan Ensor, MESSENGER Science Operations Center Lead, has reviewed and approved this document. Table of Contents 1 Purpose and Scope of Document 6 1.1 Purpose 6 1.2 Scope 6 2 Applicable Documents 7 3 Relationships with Other Interfaces 8 4 Roles and Responsibilities 8 5 Data Product Characteristics and Environment 8 5.1 Instrument Overview 8 5.1.1 FIPS Overview 8 5.1.2 EPS Overview 10 5.2 Data Product Overview 13 5.2.1 EPS Data Products 13 5.2.2 FIPS Data Products 15 5.3 Data Processing 21 5.3.1 Data Processing Level 21 5.3.2 Data Product Generation 22 5.3.3 Data Flow 22 5.3.4 Labeling and Identification 24 5.4 Standards Used in Generating Data Products 35 5.4.1 PDS Standards 35 5.4.2 Time Standards 36 5.4.3 Coordinate Systems 37 5.4.4 Data Storage Conventions 37 5.5 Data Validation 37 6 Detailed Data Product Specification 38 6.1 Data Product Structure and Organization 38 6.2 Handling Errors 39 6.3 Data Format Description 39 6.4 Label and Header Descriptions 39 6.5 File Naming Conventions 42 6.6 Archive Volume and File Size 44 6.7 Directory Structure and Contents for EPPS Documentation Volume 45 6.7.1 Directory Contents 45 6.8 Directory Structure and Contents for EPPS Data Volume 47 6.8.1 Directory Contents 47 7 Archive Release Schedule to PDS 48 8 Appendices 49 8.1 EPS_PITCH_ANGLES.FMT Table Columns 49 8.2 EPS_PASD_NUMERIC_DDR.FMT Table Columns 49 8.3 FIPS_PCHANG_DDR.FMT Table Columns 50 8.4 FIPS_ERPCHANG_DDR.FMT Table Columns 51 8.5 FIPS_ESPEC_DDR.FMT Table Columns 52 8.6 FIPS_NOBS_DDR.FMT Table Columns 52 8.7 FIPS_ARRDIR_DDR.FMT Table Columns 53 8.8 FIPS_FLUXMAP_DDR.FMT Table Columns 54 8.9 FIPS_NTP_DDR.FMT Table Columns 55 8.10 FIPS_ROTMSO_DDR.FMT Table Columns 56 8.11 SPICE Kernel Files Used in MESSENGER Data Products 56 8.12 CODMAC/NASA Definition of Processing Levels 57 8.13 MESSENGER Glossary and Acronym List 58 Table 1 Revision History Version Author Date Description Sections 1A L. Nguyen 5/22/2012 Initial revision All 1B M. Gannon 5/25/2012 Minor updates from APL team review All 1C J. Raines M. Gannon 10/17/2012 Updates from the EPPS PDS Peer Review of the Sample Archive for DDR All 1D P. Bedini 1/29/2013 Editorial updates All 1E M. Reid 1/29/2013 Replaced text indicating a draft version of this document with approved & release version. Document Review, pg. 2 1F J. Raines M. Gannon 11/06/2013 Updates to incorporate new FIPS Advanced Products All 1G G. Ho J. Raines S. Ensor 1/17/2014 Updates to DDR descriptions and applicable documents 1.2, 2, 5.2.1 1H J. Raines M. Reid 6/13/2014 Added information about the FIPS Viewing Normalization products; fixed larger document formatting. 5.2.2, 5.3.4, 6.5, 6.8, 8.7, 8.8 1I M. Reid 7/16/2014 Removed references to the FIPS Pixel FOV table. They were moved to the CDR SIS. Corrected document volume directory structure diagram. 5.2.2.6, 5.3, 6.5, 6.7, 8 1J J. M. Raines M. Reid 11/19/2014 Modified to incorporate substitution of FIPS_ARRDIR product with FLUXMAP and addition of ERPCHANG product. Added ERPCHANG product. Removed FIPS_FOVPIX directory (FIPA_* files moved to Document Vol. CALIBRATION). Modifications to ROTSMO label. Formatting. 5.1.1, 5.2, 5.3.4, 6.8, 8.3, 8.7. 1K J. M. Raines M. Gannon 1/27/2015 Edits to FIPS Flux Map and FIPS Pitch Angle product descriptions. Correction of minor typographical errors. 5.2.2.3, 5.2.2.5 1L S. Ensor 1/16/2016 Final edits (partial) All 1M J. M. Raines M. Gannon 1/28/2016 Final edits 1.1.4 and others 1N M. Reid 8/10/2016 Added description of the new Daily Pitch Angle Spectrogram products. 1.2, 5.2, 5.3, 6.5, 6.8, 8.2 2A 2B M. RG. Ho, M. Reid, S. Ensor 01/10/2017 Revisions based on the November 2016 PDS peer review. Daily EPS pitch angle spectrogram products added. All 2C M. J. J. Raines 02/10/2017 Added further discussion of the FIPS data. 5.2.2.1 Purpose and Scope of Document Purpose This document serves to provide users of the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) Energetic Particle and Plasma Spectrometer (EPPS) data products with a detailed description of the EPPS instrument, data product generation, validation, and storage. Note that the EPPS is made up of two instrument subsystems, the Fast Imaging Plasma Spectrometer (FIPS), and the Energetic Particle Spectrometer (EPS). The FIPS and EPS are described in individual sections within this document. They are referred to separately when necessary and referred to as the EPPS instrument when dealing with areas common to both instruments. The FIPS covers the lower energy range of particles and measures the mass per charge (m/q), energy per charge (E/q), and incoming direction of each charged particle. The EPS covers the higher energy range and measures mass, energy, and incoming direction of each particle. The MESSENGER EPPS data products are deliverables to the Planetary Data System (PDS) and the scientific community that it supports. All data formats are based on the PDS standard. Scope The EPPS science data are divided into two categories: Level 2 edited raw data (referred to as experiment data records or EDRs) and processed data (referred to as reduced data records or RDRs). RDRs are generated from EDRs, and represent data calibrated to a physical unit such as particle intensity (Level 3), resampled Level 4 data products, or derived Level 5 data products. RDRs consist of Calibrated Data Records (CDRs), Derived Data Records (DDRs), and Derived Analysis Products (DAPs). This Software Interface Specification (SIS) describes the EPPS DDR data products. For EPS, DDRs consist of three products: pitch angle values, pitch angle distribution spectrograms over selected ranges of energies for selected time periods, and daily pitch angle distribution spectrograms. For FIPS, DDRs consist of seven products that provide data for spatial and temporal distributions of observed density for major ion species, and for selected ion species and time periods, energy spectra, pitch angle distributions, ion flux, density, temperature, and pressure, and viewing normalizations for each energy scan. The DDR data were delivered to the PDS as CODMAC (Committee on Data Management and Computation) Level 4 data. EPPS's DDRs are formatted to include standard PDS labels. A detailed description of all data products in the EPPS DDR follows. In addition, this SIS describes the EPPS documentation volume, which contains products related to both the EDR- and RDR-level archives. The contents of the documentation volume enables one to conduct useful analysis of the DDRs. The documentation volume is described in greater detail in section 6.6. Applicable Documents The MESSENGER EPPS SIS is responsive to the following documents: Planetary Data System Standards Reference, Feb 27, 2009, Version 3.8. JPL D-7669, Part-2. MESSENGER Data Management and Archiving Plan. The Johns Hopkins University, APL. Document ID number 7384-9019 MESSENGER Mercury: Surface, Space Environment, Geochemistry, Ranging; A mission to Orbit and Explore the Planet Mercury, Concept Study, March 1999. Document ID number FG632/ 99-0479 [PLR] Appendix 7 to the discovery program Plan; Program Level Requirement for the MESSENGER Discovery project; June 20, 2001. The following documents may be referenced for details on the EPPS instruments: Livi et al., MESSENGER Energetic Particle Spectrometer (EPPS/EPS) Calibration Report, 2004 (at PDS Geosciences node: messgc_0001/EPS/EPS_CAL_RPT). Zurbuchen et al. (The Fast Ion Plasma Spectrometer (FIPS) calibration report, MESSENGER Project report, 2004) Andrews et al. (The Energetic Particle and Plasma Spectrometer Instrument on the MESSENGER Spacecraft, Space Science Reviews Volume 131, Numbers 1-4, August 2007) Raines et al. (Distribution and compositional variations of plasma ions in Mercury's space environment: The first three Mercury years of MESSENGER observations, Journal of Geophysical Research, 118, p1604-1619, 2013) Gilbert et al. (Background noise in space-based time-of-flight sensors, Reviews of Scientific Instrumentation, in review, 2014) Gershman et al. (Post-processing modeling and removal of background noise in space-based time-of-flight sensors, Deep Blue, 2013, http://hdl.handle.net/2027.42/100358) Raines et al. (MESSENGER observations of the plasma environment near Mercury, Planetary and Space Science 59, p2004-2015, 2011) Ho et al. (Spatial distribution and spectral characteristics of energetic electrons in Mercury's magnetosphere, J. Geophys. Res., doi:10.1029/2012JA017983, 117, 2012) Gershman et al. (Magnetic Flux Pile-up and Plasma Depletion in Mercury's Subsolar Magnetosheath, Journal of Geophysical Research: Space Physics, 118, p7181-7199, 2013) Slavin et al. (MESSENGER Observations of Extreme Loading and Unloading of Mercury's Magnetic Tail, Science, 329, p665-668, 2010, doi: 10.1126/science.1188067) Ho et al. (Observations of Suprathermal Electrons in Mercury's Magnetosphere during the three MESSENGER Flybys, Planetary and Space Sci., 59, p2016-2025, 2011) Relationships with Other Interfaces The EPPS DDR data products were stored at the MESSENGER Science Operations Center (SOC) during the MESSENGER mission. The data products were transferred to the PDS Planetary Plasma Interactions (PPI) Node according to the delivery schedule in section 7. The data in the DDR files is stored in PDS ASCII TABLE objects unless stated otherwise (section 5.2). Roles and Responsibilities The roles and responsibilities of the instrument teams, The Johns Hopkins University Applied Physics Laboratory (APL), Applied Coherent Technology Corporation (ACT), and the Planetary Data System (PDS), are discussed in sections 5.3.2 and 5.3.3. Data Product Characteristics and Environment Instrument Overview FIPS Overview The Fast Imaging Plasma Spectrometer (FIPS) measures the energy per charge (E/q), time-of-flight (TOF), and incident angles for plasma ions entering the sensor. Intensities, velocity distributions, and mass per charge (m/q) distributions are derived from these measurements and make up FIPS primary science data. These data are used to understand the kinetic properties, angular distributions, and composition of Mercury magnetospheric ions, and contribute to the characterization of the planetary magnetic field. Ions measured by FIPS pass through an electrostatic analyzer (ESA), located at the entrance to the sensor; a post-acceleration chamber between the output of the ESA and the carbon foil; and a time-of-flight telescope. The ESA at the entrance to FIPS acts as a wide-angle lens for ions, with a 1.4 sr field of view. It allows only ions with a specific E/q band to enter through its output plane. This band is stepped through 64 values to complete one measurement cycle (scan), nominally from 0.046-13.3 keV/e. FIPS is normally operated in one of two stepping rates: one step per second (normal mode), or one step per 100 milliseconds (burst mode). When delays due to high-voltage ramp-ups are included, these result in cycle times of 64 sec and 8 sec, respectively. The operation of FIPS is highly configurable via table upload. The time spent in each step can, in principal, be set to arbitrary values, different for each step (nominally set at 100ms/1s for burst/regular mode). Associated with each E/q step is a deflection voltage, a threshold, a settling time, and an integration (dwell) time. Ions exit the output plane of the ESA and are then accelerated in the post acceleration chamber. This acceleration is done to give low-energy ions sufficient energy to penetrate the carbon foil. The acceleration also helps to reduce energy straggling and angular scattering - effects that cause degradation in mass resolution and imaging. When ions exit the carbon foil, secondary electrons are liberated. These electrons travel to the Start MCP (microchannel plate), providing a timing-start signal and incident angle information via impact location on a position-sensing anode. The ion then travels through the TOF chamber and strikes the Stop MCP, providing a timing-stop signal and allowing computation of TOF. From E/q and TOF, m/q can be computed. FIPS can measure species from H to Fe, 1-60 amu/e (or higher). Individual ions are identified in FIPS data from their E/q and TOF measurements. A simple model is used to predict the TOF range expected for each ion as a function of E/q, referred to as the E/q-TOF track for that ion. This model includes the effects of energy lost upon passage through the carbon foil, as well delays due to electron flight time and electronic processing. All events with measured TOF within the predicted range for a particular ion are assigned to that ion. To improve signal to noise, E/q-TOF tracks for some ions are grouped together. In this dataset, H+, He+, and He2+ are assigned from their respective individual ion tracks. Two ion groups are defined: O+ group (m/q = 16 - 20; including O+ and water group ions) and Na+ group (m/q = 21-30; including Na+, Mg+, and Si+). Additional details concerning this process are given in [8]. Figure 1 Cross-section of the FIPS sensor showing both the ESA and TOF section [7]. Ions are analyzed by their energy per charge, 2D position, and total time of flight. FIPS uses a double coincidence technique to greatly reduce background noise. However, spurious double-coincidence counts still do occur. These counts come from two main sources: the extension of very high count proton measurements into other times of flight, and the release of small numbers ions from surface processes within the instrument [9]. While all major ion species reported here can be analyzed from the raw data, accuracy is significantly improved by removing these spurious counts. A detailed noise model and removal method has been developed [10] and is employed on the data in this work at the individual scan level. After species are identified in E/q-TOF space and noise counts removed, the resulting counts for species s (Ci,s) at each measured (E/q)i are transformed to phase space density (fi,s) in units of s3 m-6. Using the CDR fluxes (Ji,s) in sec-1 cm-2 sr-1, this conversion is achieved using the following relationship: f_(i,s)=J_(i,s) m_s/(v_(i,s)^2 C) where vi,s is velocity, ms is ion mass (in amu) and C is a unit conversion factor, 1.6022 10-20 (cm2 s keV)-1 . The details of the conversion of counts to phase space density are provided in the EDR2CDR document, available in the CALIBRATION directory of the EPPS documentation volume. Details of FIPS operations can be found in [7]. EPS Overview EPS is a compact TOF telescope with two main components: a TOF section and a Solid State Detectors (SSD) array. The SSD array comprises six ion-implanted planar silicon detectors, each with four pixels (two dedicated to ion measurements and two to electron measurements) for a total of 24 SSD elements. Particles enter the system through a mechanical collimator that delimits the look direction into the instrument. Particles that pass through the collimator then transit through a thin, composite Start foil (polyimide + aluminum, 10 ?g/cm2) and onto the TOF region of the instrument. Figure 2 Cross-section of the EPS sensor. The particle tranverses from left to right in the figure and terminates at the SSD. The primary particle generates secondary electrons when it passes through both the front and stop foil. These electrons are being steered toward the anodes at the bottom of the figure. Electrons are released from the inner surface of the Start foil and focused to a well-defined region on an MCP to generate the START signal in a dedicated anode. The incident ions are not significantly affected by the electric fields of the focusing optics. After a 6 cm flight path, ions traverse the Stop foil, which is a polyimide + palladium (19 ?g/cm2) composite foil. The secondary electrons released by the stop foil are steered to the MCP and generate the STOP signal. Electron trajectory simulations show that there is less than 2 ns dispersion in the transit time of the secondary electron from the foil to the MCP. Sub-nanosecond dispersion is required so as not to misidentify ion species. If both a START and STOP signal (double coincidence) are registered, then the time, t, for the particle to travel a known distance (d=6 cm) can be determined. For triple coincidence we must have the START, STOP, and also the energy measured (Emeas) by the SSDs. Using these measured parameters, we can calculate the mass (M) and the incident energy (E) of each ion using the following equations: Etrue takes into account the small energy loss of the ions passing through the stop foil, and the energy loss and pulse-height defect in the SSDs. EToF takes into account the even smaller energy loss or gain in the start foil, and may also include up to ~2.5 keV electrostatic pre-acceleration of ions that remain charged on exiting the start foil. If the energy of the incident particle is not large enough to trigger the SSD, then only t is measured and the pulse height of the start anode is used to discriminate whether it is a light (M~1 amu), or heavy (M > 1 amu) ion. At the same value of TOF, heavy ions have been shown to generate substantially more secondary electrons than do protons. Besides composition measurements, the particle's angular direction can be determined. The pair of start and stop anodes provide the polar entrance angle of the incident particle. The polar angle of +80 to -80 is divided into six equal sectors (nominally 27). Electron measurements Energetic electrons have higher penetration power than ions at the same energy. The SSDs dedicated to electron detection in EPS are covered by a thin layer (flashing) of 1?m of aluminum. This dead layer stops protons with energy less then ~250 keV; Electrons, on the other hand, lose less than 10 keV by the interaction with this dead layer. Electrons are identified in EPS by the presence of an energy signal. The TOF spectra collected in the adjacent SSD (without flashing) are used during ground data analysis for checking and correcting for the proton contamination. "Calibration" for a particle instrument like EPS means determining the following: Transfer function from counts into flux (physical units) Characteristic of "Rate-out" versus "Rate-in" Response to low energy and high energy particle background Response to visible and ultraviolet light Response to high magnetic field All these functions need to be characterized and the relevant parameters need to be determined before flight. Transfer Function Flux, differential intensity, and phase space density The number of particles N that traverse an area A during a time t can be characterized by the flux F [1/cm2/s] N= A * t * F or by the intensity I [1/cm2/s/sr] N= A * t * ? I cos() d? where ? is solid angle and is angle to the area normal. Here, the geometric characteristics of the sensor determine the limits on the integration. Often used is the quantity differential intensity f [1/cm2/s/sr/keV], defined as the number of particles with energy between E and E+?E that traverse the area A during the time t, where N(E)=f(E) * A * t * ?? * ?E In three dimensions, with ? being the polar angle and f the azimuthal angle of a polar reference system: d3N(E,?,f)=f(E, ?, f) * A cos() * t * dE cos ? d? df Note that f(E, ?, f) is related to the phase-space density psd (number of particles in the configuration space element d3R and with velocity between v and v+ d3v) by the simple relationship in the non-relativistic limit (valid for ions measured by EPS but not for the higher energy electrons): psd(s3/ cm6)=f(1/cm2/s/sr/keV) * m/v2 For relativistic particles, one generally utilizes momentum space rather than velocity space, and the corresponding expression is: psd(s3/gm.cm6) = f(1/cm2/s/sr/keV) / p2 Where "p" is momentum. Definition of sensor transfer function and geometric factor The number of counts N of particles of mass m, in the energy band around mean energy E, angular band ?? around mean polar direction ?, and angular band ?f around the mean azimuthal direction f, measured by the instrument during the time dt can be expressed as: N(E, ?, f; m) = dt * ??E ??? ??f f(E, ?, f; m) * A cos() * dE cos ? d? df If f(E, ?, f) is a Dirac d function (monoenergetic, infinitely narrow beam), then N(E, ?, f; m) = dt * f(E, ?, f; m) * G(E, ?, f; m) Where G(E, ?, f; m) [cm2 sr keV] is the transfer function of the instrument. In the other limit, when the flux is completely isotropic (all directions the same) N(E; m) = dt * f(E; m) * GF(E; m) GF is called geometric factor. In this representation we also include the species and energy dependence, which is a measure of the efficiency of the system (count rate/flux), and typically is a function of energy and species. Since the true geometric factor (or GF') is only the geometric mean (constant for energy and species) of the entrance system, we can rewrite GF = GF'*?(E, m, ?, f). The goal of the calibration is to characterize the function GF(E, ?, f; m), so that from measurements of the count rates it is possible to constrain f(E, ?, f; m). Note that an exact inversion of the integral is rarely possible, and we can compute only the coefficients of some tailored expansion of f(E, ?, f; m), such as in spherical harmonics (Legendre polynomials). The accuracy of these coefficients depends on both the raster coverage of the measurements and on the calibration. Collimator The EPS collimator consists of four concentric half circular plates that have holes aligned with a common point of origin at the center of the EPS TOF telescope. The size and number of collimator holes define the geometric factor GF of the instrument. The many-holes collimator design minimizes the scattering of ions and electrons at the collimator while restricting the field-of-view (FOV) of the instrument. GEANT4 simulation (which can stimulate the full GF(E, ?, f; m), not just the GF') shows that the geometry factor for the total SSD area to be 0.016 cm2 sr. The simulation accounted for gaps between the detectors, but did not allow for the guard ring dead area between the large and small pixels (~1mm wide) or the losses in the two grids used to mount the thin foils. Hence, before grid losses, the total large pixel geometry factor is therefore GFSSD = 0.0152 cm2 sr, and the small pixels would be 0.0008 cm2 sr. The grid losses are actual blockages, so these should be included in the geometry factor. EPS used 40-lines-per-inch grids on the foils that are 86% transmissive. Therefore, for the 12 large pixels, we have a total geometry factor of 0.862x0.0152, or 0.011 cm2 sr, and each large pixel is 1/12 of that, or GFSSD-Large = 0.001 cm2 sr. For the 12 small pixels, we have a total geometry factor of 5.6x10-4 cm2 sr, or GFSSD-Small = 4.7x10-5 cm2 sr per pixel. The current simulation does not model the scattering of low energy ion and electron in the collimator; hence the current value of GFSSD is constant with energy and look direction. Disclaimer: EPS suffered a high-voltage failure shortly after launch [15]; subsequently the TOF section never operated in flight. Hence the following paragraph does not apply to the EPS flight data, we include here for completeness only. GFTOF for the Low Energy Ions (TOF-only) is roughly twice the SSD values, or ~0.03 cm2 sr. Note that the needed Transfer Factor GF depends also on the counting efficiency ? (E, m, ?, f) which depends, in turn, on species and instrument mode. However, these values were never conclusively determined. During the time of instrument check out shortly after launch, EPS's TOF section suffered a failure [15]; subsequently, EPS lost its ability to measure ions by elemental mass species. All in-flight EPS data contains null TOF values, hence, EPS can now only measure N(E) = dt * f(E) * GFSSD GFSSD is now the geometric factor and represents a measure of the efficiency of the system (count rate/flux), and is constant with look direction, energy and species. This is the standard approximate conversion of count rate to intensity assuming the channel efficiency is part of the geometry factor. The shape of the energy spectrum also affects the response, here we assume a monotonic energy spectra within the energy width of the channel. Data Product Overview The DDR data products generated by the EPS and FIPS subsystems are described in this section. For all of the DDR products there is a detached PDS label file, which describes the contents of one data file. Each label file has the same base name as the data file it is describing, with the extension ".LBL" to denote a label file. The label file defines the start time and end of the observation, product creation time, and the structure of the ASCII tables. Each data file contains the data collected on a given Earth day. EPS Data Products The EPS portion of the data archive consists of tables of EPS pitch angle values, pitch angle distribution function spectrograms in the form of browse plots, and daily pitch angle distribution spectrograms in the form of browse [SE1]plots and text data files. These data products are derivate from the "Shaped" channel on EPS which is an integrated (hardware) channel. The hardware channel responded to all particles (ion and electron) that are above the threshold (~30 keV). Our experience at Mercury's magnetosphere is that the primary particles are mostly energetic electrons. Please note that the D03 detector on the EPS has a very high background and is not useable for any of these science data products. Pitch Angle Computation The pitch angle is defined as the instantaneous angle between the particle flow direction and the measured in-situ magnetic field, with 0 degrees being where the particle is traveling along the field and 180 degrees where the particle is traveling in the opposite direction. Both vectors (the particle flow direction and the magnetic field) are measured in the spacecraft frame. The pitch angle values are calculated using the EPS odd-shaped channels. These hardware channels correspond to ions or electrons that are above the instrument threshold (nominally ~35 keV), and are not affected by prioritization in the instrument software. For a rapidly falling energy spectrum, these counts would be dominated at the lowest energies. These values should be used in conjunction with the rate channels for which intensity is computed. The particle flow direction for each of the six EPS look directions is obtained by using the MESSENGER SPICE pointing kernels (c-kernels) and the EPS frame kernel. The magnetic field measurements are taken from MESSENGER Magnetometer (MAG) Level 1 1-second averaged data; see the MAG instrument DDR SIS. Pitch Angles Product The pitch angle value tables contain the pitch angle for each of the six look directions reported at the same cadence as the EPS LoRes Spectral rate measurements (see EPPS CDR SIS document). Each file thus has a one-to-one relationship with a corresponding LoRes spectral file. Constant normalization factors and background subtractions have been applied to these channels to offset any bias in the threshold setting. Channel 01 is set to be one and all other channels are normalized to that. The channel chosen for normalization is arbitrary and does not impact the use of these data products as they are supposed to be used in conjunction with the properly calibrated rate channels. The formula used is Adjusted Value = Scaling * Raw Value + Offset. The constant scaling and offset values are given in Table 2. Please note that the D03 detector on EPS has a very high background and is not useable for any science data product. Select Pitch Angle Distribution Spectrogram Product The pitch angle distribution shown in the pitch angle spectrogram browse [SE2]plots is plotted using the pitch angle values and time-averaged within the time interval accordingly. We averaged the particle measurement in 120-second bins. Pitch angle bins are 22.5 degrees wide, and run from 0 to 180 degrees. For the pitch angle distribution spectrogram, the color scale is normalized to the maximum counts for the time interval covered by the current plot (i.e. the intensity color scale varies between plots). The products provided in the EPS_PITCH_ANGLES_SPECTROGRAM directory in this volume are selected based on the criteria outlined by Ho et al. [JGR, 2012] on events that are at least 10 times above the instrument background at the lowest energy channel 36-57 keV. Pitch angle spectrogram products are provided for all orbital periods in the EPS_PA_DAILY_SPECTROGRAM directory. Channel Name Scaling Offset SHAPED_COUNTS D00 1.0412691533565521 15.11127820611 SHAPED_COUNTS D01 1 0 SHAPED_COUNTS D02 0.7014738321304321 10.141375184059143 SHAPED_COUNTS D03 SHAPED_COUNTS D04 1.338530421257019 18.39651709794998 SHAPED_COUNTS D05 1.3527332693338394 7.795897737145424 SHAPED_COUNTS D06 1.4293411076068878 27.3230662047863 SHAPED_COUNTS D07 0.805070623755455 3.0807372108101845 SHAPED_COUNTS D08 0.9233275651931763 32.62595450878143 SHAPED_COUNTS D09 0.5404207110404968 -0.39973045140504837 SHAPED_COUNTS D10 0.31776440143585205 22.942654877901077 SHAPED_COUNTS D11 0.15649390034377575 -22.306587459519506 Table 2 Constant values used to adjust the count rate for the shaped channels. D01 is the channel to which all others were fit in order to arrive at these values, while D03 is unlike the others and cannot be fit, so it remains unadjusted. Daily Pitch Angle Distribution Spectrogram Product The Daily Pitch angle Spectrogram products are similar to the Select products described above, but are provided as daily products that cover the entire orbital phase of the mission. Additionally, a text data file (.TAB) accompanies each browse plot. The data file contains the same pitch angle distributions as plotted in the browse [SE3]product (.PNG), but as data points. FIPS Data Products Except where noted below, these data products are derived from individual event (PHA) words, which have full angle and TOF information. Using PHA words enables the finest possible separation into ion species as well as distinguishing incident angles. Noise removal in E/q - TOF space is performed before accumulation for all ions except H+, for which noise removal is not needed. The orbital regions for which data is provided varies by product, as described below. Within these, data is provided for time steps whenever the instrument was operating in a nominal mode and when the data was of sufficient quality for scientific analysis. These conditions are met for the vast majority of times throughout the mission. In particular, many of these products are provided in regions determined by hand-picked or modeled bow shock and magnetopause boundaries. Boundary picking was done by the MAG team at a level of accuracy sufficient for the relatively low time resolution FIPS data (10s - 60s). Where these were not available, the model given by Slavin et al. [14] is used. Differential Energy Flux Spectra Differential energy flux spectra in units of (keV/e)-1 sec-1 cm-2 sr-1 are provided for all 5 ion species throughout the entire magnetosphere and magnetosheath regions crossed by the spacecraft during each orbit. These spectra cover the full energy per charge range of FIPS, which ws 0.046 - 13.3 keV/e during most of the mission. See the FIPA_EYYYYDOY.DAT file for exact energy range. They are derived in a manner completely analogous to CDR differential energy flux spectra (dJi,s/dEi) except that the total number of PHA event words for a given species at each E/q step is used in place of on-board accumulated count rates (except protons). See EPPS_FIPS_EDR2CDR.DOCX for more details. For protons, this product is derived from on-board accumulated rates just as for the CDR version, so that for protons only this product is a duplicate of the CDR version. This duplication was intended to allow users to primarily use DDR data only in their scientific analysis. However, the differential energy spectra for protons only are not organized according to the FIPA_EYYYYDOY.DAT files as are the rest of the ion species in this product. The protons are instead organized by E/q step, just as they are in the CDR version. Please refer to the EPPS CDR SIS for more information. The CDR proton rate spectra product is also needed to determine which of the available E/q tables to use for all species in this product. This requirement to use CDR products in conjunction with their DDR counterparts was unintended and will be removed in a future release. Observed Density Observed density (nobs,s, in cm-3) for all ion species is provided for all 5 ion species throughout all orbit regions. This product serves to determine the spatial and temporal distribution of these ions and is the foundation DDR data product for FIPS. For protons, this product is derived from on-board accumulated rates rather than PHA event words, for much higher signal to noise ratio. Observed densities are computed from differential energy flux spectra Ji,s in two stages: First, dJi,s/dEi is converted to phase-space density (fi,s, s3 m-6) f_(i,s)= 6.2414?10?^19 (m_s/(v_(i,s)^2 ))(?dJ?_(i,s)/?dE?_i ) Second, fi,s integrated over all velocities (vi,s) and solid angle (?O) for a full scan to yield observed density (nobs,s) for species s It is important to note that no correction has been made for limited field of view in this calculation. This correction requires knowledge of the true velocity distribution function in which the measured particles reside and is therefore beyond the scope of this data product. The net result is that nobs values reported are not in general equal to the ambient plasma density. More information about calculation of nobs and the limited FIPS field of view can be found in [10, 11]. Angular Flux Maps Integrated ion flux, Js(?,?), as a function of flow direction in MSO coordinates are provided for all 5 ion species throughout the entire magnetosphere and magnetosheath regions crossed by the spacecraft during each orbit. This product replaces the Arrival Direction Histogram (ARRDIR) product as it more a more useful representation of plasma behavior. Angular Flux Maps may be used in conjunction with pitch angle distributions to understand the location and motion of ions relative to Mercury. The discrete integration of phase space density (f) is performed over ion speed (v) in the standard way, leaving the two angular dimensions unchanged: J_s (?,?)=?_i.giff_(i,s) (?,?)v_(i,s)^3 dv_i Very low count rates can make this product difficult to interpret. For some ions, this situation is mitigated by summing over several, often many, FIPS scans until sufficient counts are available. In other cases, counts for a particular ion are so low the required number of counts would require summation over large regions of space, making the arrival directions again difficult to interpret. Therefore, these cases are not included in the data. Summing over multiple scans brings with it the need to normalize the arrival direction distributions for the amount of time that a particular incident angle could be observed. In normal operations, the MESSENGER spacecraft rotates around the spacecraft Y-axis (YMSGR) to optimize viewing for different instruments. FIPS orientation is fixed relative to the spacecraft, so that the FIPS FOV rotates with the MESSENGER spacecraft. This results in significant variation in observing time for look directions in MSO coordinates. These variations in observing time have been normalized out of the fluxes included in this data product. Despite this normalization, the finite sensitivity of FIPS can still result in reduced measured ion flux from arrival directions with low observing time. In practice, this does not usually affect the typically qualitative interpretation of these maps. The user could mitigate this effect by reducing the variability of observing time: Only flux from directions that are viewed within a fixed fraction (e.g. 0.1) of the maximum observation time for a given time accumulation could be included in arrival direction histograms. This restriction is not applied to delivered data from this data product. The FLUXMAP data product is constructed and normalized as follows: Two arrays representing a full 4p steradian FOV are created at the 10 native angle binning of FIPS. This results in an 18 x 36 element array for the polar and azimuthal angle bins, respectively. The first of these is used for the average flux, FLUX, while the second is used for the average measurement time, VIEWTIME. The FLUX matrix for each energy scan is created from PHAs as follows: Find the rotation matrix, ROTMSO, (described below) for the day (YYYYDOY) and index which corresponds to the scan Form the unit velocity vector: Convert the incident polar and azimuthal angles of the event from FIPS spherical coordinates to FIPS Cartesian coordinates. Use the usual manner for spherical to Cartesian conversion, using 1 for the r component. Invert the direction by multiplying all components by -1. This changes the FOV coordinates to flow direction. Rotate to MSO via multiplication by the ROTMSO. Convert the resultant MSO vector to spherical coordinates. Round angles down to the nearest 10. Add the flux value multiplied by the PHA solid angle into a temporary 18 x 36 matrix using the rounded-down angles. Convert entire FIPS spherical MCP map to MSO using the steps from (ii) for each coordinate pair. Round angles down to the nearest 10. Add the MCP pixel solid angles into a second temporary 18 x 36 matrix using the rounded-down angles. Divide the temporary flux by the temporary solid angle,, element-by-element. The VIEWTIME matrix for each energy scan is created as follows: Calculate the average step measurement time for the scan Add that value into every element of the VIEWTIME matrix Set to 0 any matrix location for which the corresponding solid angle matrix value is 0 (this will remove unobserved locations from the result). Sum FLUX and VIEWTIME over all accumulation scans Form the properly normalized product by dividing (element by element) the FLUX (summed over scans) and VIEWTIME (summed over scans). FLUXMAP=(?.gifFLUX)/(?.gifVIEWTIME) Arrival Direction (Retired Product) This product class was retired after the Mercury Orbit Year 2 mission phase. The Angular Flux Map products described in the previous section supersede it. Since the Arrival Direction products remain in version V1.0 of the data set in the FIPS DDR archive volume at the PDS, a description of them is retained in this document. This product provides observed density as a function of arrival direction in the instrument frame (incident polar and azimuthal angle) in MSO coordinates for selected ions and regions around Mercury. The discrete integration of phase space density (f) is performed in the velocity dimension (v) only, leaving the two angular dimensions unchanged: n_(obs, s) (?,?)=?_i.giff_(i,s) (?,?)v_(i,s)^2 dv_i The above quantity, termed "observed density", is analogous to density in each angular bin formed only from the counts observed in that bin. It differs from that performed in the Angular Flux Map product by one power of v which introduced in that product to change from a density to a flux quantity. The Arrival Direction Histogram product is identical in several ways to the Angular Flux Maps product that replaced it: It can be difficult to interpret due to very low count rates, a problem which is partially mitigated by summing over FIPS scans. This summing then requires proper normalization, performed in exactly the same manner as described in detail for Angular Flux Maps. This product may be used in conjunction with pitch angle distributions to understand the location and motion of ions relative to Mercury. The ARRDIR data product is constructed and normalized exactly as described above for the Angular Flux Maps, with two exceptions (with the ARRDIR array replacing the FLUXMAP array): The velocity vector must NOT be inverted by reversing the sign of each component. Multiply the weight from each PHA is added into the ARRDIR array. It is not multiplied by the particle speed. (Modify step 2.b.iv. above.) Pitch Angle Distributions For an ion in the presence of a magnetic field, the angle between the velocity vector and the local magnetic field direction is referred to as pitch angle. For populations of plasma ions, pitch angle distribution histograms can be formed by counting the number of ions within a given pitch angle range (PCHANG data product). This histogram may also be separated into measured E/q bins, forming energy-resolved pitch angle distributions (ERPCHANG data product). Pitch angle distributions give information on the velocity of ions along magnetic field lines, character of velocity distributions and the general plasma environment. Care must be taken when interpreting pitch angle distributions in the instrument frame (such as these) when the plasma has a non-negligible bulk velocity. Both the PCHANG and ERPCHANG products are provided for all 5 ion species throughout the entire magnetosphere and magnetosheath regions crossed by the spacecraft during each orbit. The pitch angle distribution for a given time period consists of a histogram of these angles in 10 bins for all the ion events (PHA words) in the time period. Energy-resolved pitch angle distributions are also separated into the native FIPS E/q stepping bins. Pitch angle distributions are provided for selected ions and time periods, when sufficient statistics exist to make the product meaningful for scientific studies. The PCHANG data product is normalized as follows: Two arrays representing pitch angles 0-180 are created at 10 binning, resulting in two 18-element arrays. The first of these is used for the average flux, FLUX, while the second is used for viewing normalization, VIEWTIME. The FLUX array for each energy scan is created from PHAs as follows: Find the rotation matrix, ROTMSO, (described below) for the day (YYYYDOY) and index which corresponds to the scan Form the unit velocity vector: Convert the incident polar and azimuthal angles of the event from FIPS spherical coordinates to FIPS Cartesian coordinates. Use the usual manner for spherical to Cartesian conversion, using 1 for the r component. Invert by multiplying all components by -1. This changes the FOV coordinates to flow direction. Rotate to MSO via multiplication by the ROTMSO. Average the MAG CDR vectors (already in MSO) that fall within the FIPS scan time to one value Calculate the angular separation between this vector and the average MAG vector. Round down angle to nearest 10. Add the flux value multiplied by the PHA solid angle into a temporary 18 element array using the rounded-down angles. Convert entire FIPS spherical MCP map to MSO using the steps from (ii) for each coordinate pair. Round angles down to the nearest 10. Calculate the angular separation between the MCP vectors and the average MAG vector. Round down angle to nearest 10. Add the MCP pixel solid angles into a second temporary 18 element array using the rounded-down angles. Divide the flux temp by the solid angle temp, element-by-element. The VIEWTIME array for each energy scan is created as follows: Calculate the average step measurement time for the scan Add that value into every element of the VIEWTIME array. Set to 0 any array location for which the corresponding solid angle array value is 0 (this will remove unobserved locations from the result). Sum FLUX and VIEWTIME over all accumulation scans Form the properly normalized product by dividing (element by element) the FLUX (summed over scans) and VIEWTIME (summed over scans). PCHANG=(?.gifFLUX)/(?.gifVIEWTIME) The ERPCHANG product is formed in an analogous fashion, with the additional separation by E/q step. In this case, the weighting value in the 'FLUX' numerator is average phase space density. Kinetic Properties Under several conditions, full number density, n, temperature, T, and pressure, P, can be calculated directly from counts. (In contrast, when these conditions are not fulfilled, only the partial, observed densities, described above in 5.2.2.2, can be determined.) The conditions are as follows: There must be sufficient counts to produce a well-defined energy spectrum. When necessary, counts from multiple scans are summed to meet this criterion. The plasma must be subsonic. That is, where vb is the plasma bulk velocity and Vth is the plasma thermal velocity. The plasma must be nearly isotropic. That is, where T? is the plasma temperature perpendicular to the magnetic field and T|| is the plasma temperature parallel to the magnetic field. This data is provided where these assumptions are most likely to hold: a) throughout the magnetosphere and b) the dayside magnetosheath within a 45 cone angle around the XMSO axis. Furthermore, the data are averaged over multiple FIPS scans so as to minimize the effect on the recovered n and T of transients (e.g. high speed flows) which violate the assumptions. However, for studies involving features near the time scale of the averaged data and/or inside the magnetosheath, users are strongly cautioned to evaluate the validity of the assumptions themselves. This is most easily done by comparing velocity distribution functions, computed from differential energy flux spectra and averaged to the same period as this data, to those formed from a non-drifting Maxwell-Boltzmann velocity distribution formed from the recovered n and T (with bulk speed of zero). For protons, this product is derived from on-board accumulated rates rather than PHA event words, for much higher signal to noise ratio. Data is summed over multiple scans to increase signal to noise. Furthermore, this data is produced only those accumulations which exceed a minimum count level (20 counts). Extensive testing has shown that computing these products from PHA event words for ions heavier than protons is not practical at fixed time steps of the order of a few minutes. Therefore, these ions are not included in this product. When these conditions are fulfilled, we compute n and vth directly from measured velocity distribution functions (formed from differential energy flux spectra) using a numerical method of solving the system of moment equations [Gershman et al., 2013]. T and P are then calculated using the usual relations: where kb is the Boltzmann constant. The units of the recovered plasma parameters are cm-3, MK, and nPa for n, T, and P, respectively. The quoted uncertainties of these parameters are a function of only number of counts used to create each distribution, following Gershman et al., 2013. There are small additional uncertainties that result as the measured energy spectra approach the limits of conditions (2) and (3) above. These additional uncertainties are difficult to quantify and not included in the reported uncertainties. Viewing Normalization The FIPS Viewing Normalization data product contains a rotation matrix (ROTMSO) from FIPS cartesian to MSO coordinates, for each FIPS energy scan. This matrix can be used to rotate ion incident angles in CDR PHA data into MSO coordinates needed for producing normalized directional maps (e.g. FLUXMAP or PCHANG) for arbitrary time resolutions, in multiples of 10s. Data Processing Data Processing Level There is one EPPS PDS Documentation Archive Volume and one EPPS PDS Data Archive Volume. The data volume contains level 4 CODMAC data products, also known as DDRs. Each product has a unique file name and conforms to the file naming convention in section 6.5. All DDR products were stored at the MESSENGER Science Operations Center (SOC) during the MESSENGER mission. Volumes were transferred to the PDS PPI Node following the procedure in section 5.3.3. Data Product Generation The EPPS DDR files were produced by the EPS and FIPS teams. A Java program derived from the MIDL (Mission Independent Data Layer) analysis software developed by APL was used to generate the DDRs. The FIPS data were produced using Interactive Data Language (IDL) software routines developed at the University of Michigan. The DDR data products were made available to the MESSENGER Science Team for initial evaluation and validation. At the end of the evaluation and validation period, the data were organized and stored in the directory structure described in section 6.8 for transfer to the PPI Node. The transmittal process is described in section, 5.3.3. An initial release of the documentation volume accompanied the initial release of the data volume. Thereafter, updates to the documentation volume were made with each data delivery to document the data quality for the delivery, changes to products including calibration updates, and other updates as appropriate. PDS provides public access to the data products through its online distribution system. These products support engineering analysis, direct science analysis, and construction of other science products. Data Flow The MESSENGER SOC operates under the auspices of the MESSENGER Project Scientist to plan data acquisition, generate, and validate data archives. The SOC supports and works with the Mission Operations Center (MOC), the Science Team, instrument scientists, and the PDS. Figure 1 MESSENGER data flow shows the flow of data within the MESSENGER project and out to PDS. The MOC handles raw data flow to and from the MESSENGER spacecraft and the SOC converts the raw telemetry into EDRs, which are subsequently converted into CDRs and DDRs by the Science Team. Documentation, CDRs, and DDRs are delivered to the PDS Planetary Plasma Interactions (PPI) node. All SPICE kernels used in CDR and DDR processing are delivered to the PDS Navigation and Ancillary Information (NAIF) node. The delivery process is detailed below. The MESSENGER SOC delivered data for the EPPS DDR data volume to the PDS PPI Node in standard product packages. Each package comprises data and ancillary data files, organized into directory structures consistent with the volume design described in section 6.8. The initial release contained the documents and required files for the EPPS documentation volume, organized into directory structures as described in section 6.7. Subsequent releases to the EPPS documentation volume contained updates as appropriate. In preparation for delivery, the directory structure is compressed into a single "zip archive" file for transfer to the PDS node. The zip archive preserves the directory structure internally so that it can be recreated after delivery to the PDS node. Also included in the transfer is a checksum file created using the MD5 algorithm. This provides an independent method of verifying the integrity of the zip file after it has been sent. Within days of receipt of the delivery the PDS node acknowledges receipt of the archive and checksum file. If acknowledgement is not received, or if problems are reported, the MESSENGER SOC immediately takes corrective action to affect successful transfer. Delivery size determines the transfer mechanism: electronic or shipping a hard drive. The PDS node uncompresses the zip archive file and checks for data integrity using the checksum file. The node performs any additional verification and validation of the data provided and reports any discrepancies or problems to the MESSENGER SOC. The node performs these checks within about two weeks from receipt of the delivery. After inspection has been completed to the satisfaction of the PDS node, the node issues an acknowledgement of successful receipt of the data to the MESSENGER SOC. Following receipt of a data delivery the PDS node organizes the data into a PDS volume archive structure within its online data system. Newly delivered data are made available publicly from PDS once accompanying labels and other documentation have been validated. Labeling and Identification The PDS label conforms to PDS version 3.8 standards. For more information about this standard consult the PDS Standards Reference Document. The label is detached and in a separate PDS label file. The purpose of the PDS label is to describe the data product and provide ancillary information about the data product. There is a PDS label file for every EPPS DDR data file. There is one DATA_SET_ID assigned to the EPPS DDR data. The DDRs are further grouped into data products and are identified by the STANDARD_DATA_PRODUCT_ID keyword and the file naming convention, section 6.5. Example label file content is shown here for every DDR data product. Note that the data are contained within an ASCII table and the details of the table structure are described by an external ASCII format file (*.FMT). The columns in each format file are described separately in the Appendix. EPS Pitch Angles Label A sample EPS Pitch Angles DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ FILE_RECORDS = 5798 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 167 /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "EPSP_A2012010DDR_V1" PRODUCT_VERSION_ID = "V1" PRODUCT_CREATION_TIME = 2012-05-09T21:04:27 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "EPS_PITCH_ANGLES_DDR" SOFTWARE_NAME = "MIDLMessengerDDRGenerator" SOFTWARE_VERSION_ID = "1.0" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "ENERGETIC PARTICLE SPECTROMETER" INSTRUMENT_ID = "EPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-EPS-DDR-V1.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED EPS DDR V1.0" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" START_TIME = 2012-010T00:00:49 STOP_TIME = 2012-010T23:59:45 SPACECRAFT_CLOCK_START_COUNT = "234641115" SPACECRAFT_CLOCK_STOP_COUNT = "234727451" ^HEADER = ("EPSP_A2012010DDR_V1.TAB", 1) ^ASCII_TABLE = ("EPSP_A2012010DDR_V1.TAB", 2) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 1 BYTES = 167 DESCRIPTION = "The first record of this file is the header section. The header contains column headings to improve usability." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 7 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 167 ROWS = 5798 DESCRIPTION = " This table contains Pitch Angles between the measured flow vector direction and the magnetic field for each of the 6 sectors of the MESSENGER EPS instrument. The complete column definitions are contained in an external file found in the LABEL directory of the archive volume. Additional details are contained in the DDR SIS document." NOTE = "Data Quality: 0" ^STRUCTURE = "EPS_PITCH_ANGLES.FMT" END_OBJECT = ASCII_TABLE END EPS Select Pitch Angle Spectrogram Label A sample EPS Select Pitch Angle Spectrogram DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ RECORD_TYPE = UNDEFINED INTERCHANGE_FORMAT = BINARY /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "EPS_PAS_2012074205045_V1" PRODUCT_VERSION_ID = "V1" PRODUCT_CREATION_TIME = 2012-05-09T17:00:00 PRODUCT_TYPE = "BROWSE" STANDARD_DATA_PRODUCT_ID = "EPS_PITCH_ANGLE_SPECTROGRAM_DDR" SOFTWARE_NAME = "MIDLMessengerDDRGenerator" SOFTWARE_VERSION_ID = "1.0" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "ENERGETIC PARTICLE SPECTROMETER" INSTRUMENT_ID = "EPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-EPS-DDR-V1.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED EPS DDR V1.0" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" START_TIME = 2012-03-14T20:50:45 STOP_TIME = 2012-03-15T00:23:45 SPACECRAFT_CLOCK_START_COUNT = "240245710" SPACECRAFT_CLOCK_STOP_COUNT = "240258490" ^DOCUMENT = "EPS_PAS_2012074205045_V1.PNG" OBJECT = DOCUMENT DOCUMENT_NAME = "EPS_PAS_2012074205045_V1" DOCUMENT_FORMAT = PNG DOCUMENT_TOPIC_TYPE = "BROWSE IMAGE" INTERCHANGE_FORMAT = BINARY PUBLICATION_DATE = 2012-05-09T17:00:00 SOURCE_PRODUCT_ID = { "EPSL_R2012074EDR_V1.DAT", "MAGSC_SCIAVG12075_01_V00.TAB", "MAGSC_SCIAVG12074_01_V00.TAB", "EPSL_R2012075EDR_V1.DAT" } LINES = 400 LINE_SAMPLES = 850 SAMPLE_TYPE = MSB_UNSIGNED_INTEGER SAMPLE_BITS = 8 DESCRIPTION = "PNG file containing a spectrogram representation of the summation of the shaped count rates in detectors 0-10 except detector 3. The counts are binned in time (120 s) and pitch angle (22.5 deg). Constant normalization factors and background subtractions (see SIS for Table) have been applied to these rates." END_OBJECT = DOCUMENT END EPS Daily Pitch Angle Spectrogram Plot Label A sample EPS Daily Pitch Angle Spectrogram Plot DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ RECORD_TYPE = UNDEFINED INTERCHANGE_FORMAT = BINARY /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "EPS_PASD_IMAGE_2014100_DDR_V01" PRODUCT_VERSION_ID = "V1" PRODUCT_CREATION_TIME = 2017-005T16:43:05 PRODUCT_TYPE = "BROWSE" STANDARD_DATA_PRODUCT_ID = "EPS_PA_SPEC_DDR" SOFTWARE_NAME = "MIDLMESSENGERDDRGENERATOR" SOFTWARE_VERSION_ID = "1.0" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "ENERGETIC PARTICLE AND PLASMA SPECTROMETER" INSTRUMENT_ID = "EPPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-EPS-DDR-V1.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED EPS DDR V1.0" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" START_TIME = 2014-04-10T00:00:00 STOP_TIME = 2014-04-10T23:59:59 SPACECRAFT_CLOCK_START_COUNT = "2/039411999" SPACECRAFT_CLOCK_STOP_COUNT = "2/039498398" ^DOCUMENT = "EPS_PASD_IMAGE_2014100_DDR_V01.PNG" OBJECT = DOCUMENT DOCUMENT_NAME = "EPS_PASD_IMAGE_2014100_DDR_V01" DOCUMENT_FORMAT = PNG DOCUMENT_TOPIC_TYPE = "BROWSE IMAGE" INTERCHANGE_FORMAT = BINARY PUBLICATION_DATE = 2017-01-09 SOURCE_PRODUCT_ID = { "EPSL_R2014100EDR_V1.DAT", "MAGSC_SCIAVG14100_01_V08.TAB", "EPSL_R2014101EDR_V1.DAT" } LINES = 400 LINE_SAMPLES = 850 SAMPLE_TYPE = MSB_UNSIGNED_INTEGER SAMPLE_BITS = 8 DESCRIPTION = " PNG file containing a spectrogram representation of the summation of the shaped count rates in detectors 0-10 except detector 3. The counts are binned in time (120 s) and pitch angle (22.5 deg). Constant normalization factors and background subtractions (see SIS for Table) have been applied to these rates." END_OBJECT = DOCUMENT END EPS Daily Pitch Angle Spectrogram Data Label A sample EPS Daily Pitch Angle Spectrogram data DDR file label is shown below: PDS_VERSION_ID = "PDS3" RECORD_TYPE = "FIXED_LENGTH" RECORD_BYTES = 406 FILE_RECORDS = 720 PRODUCT_ID = "EPS_PASD_NUMERIC_2014100_DDR_V01" PRODUCT_VERSION_ID = "1" PRODUCT_CREATION_TIME = 2017-005T16:43:05 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "EPS_PASD_NUMERIC_DDR" SOFTWARE_NAME = "EPSDAILYPITCHANGLEPDSCSVFILEWRITER" SOFTWARE_VERSION_ID = "1.0" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "ENERGETIC PARTICLE AND PLASMA SPECTROMETER" INSTRUMENT_ID = "EPPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-EPS-DDR-V1.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED EPS DDR V1.0" MISSION_PHASE_NAME = "MERCURY ORBIT YEAR 4" TARGET_NAME = "MERCURY" SOURCE_PRODUCT_ID = { "EPSL_R2014100EDR_V1.DAT", "MAGSC_SCIAVG14100_01_V08.TAB", "EPSL_R2014101EDR_V1.DAT" } START_TIME = 2014-04-10T00:00:00 STOP_TIME = 2014-04-10T23:59:58 SPACECRAFT_CLOCK_START_COUNT = "2/039411999" SPACECRAFT_CLOCK_STOP_COUNT = "2/039498398" ^HEADER = ("EPS_PASD_NUMERIC_2014100_DDR_V01.TAB", 1) ^ASCII_TABLE = ("EPS_PASD_NUMERIC_2014100_DDR_V01.TAB", 2) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 1 BYTES = 406 DESCRIPTION = "The first record of this file is the header section. The header contains column headings to improve usability." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 17 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 406 ROWS = 720 DESCRIPTION = "The table contains charged particle rate data from the MESSENGER EPS instrument binned by Pitch Angle." ^STRUCTURE = "EPS_PASD_NUMERIC_DDR.FMT" END_OBJECT = ASCII_TABLE END FIPS Pitch Angles Label (PCHANG) A sample FIPS Pitch Angles DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ FILE_RECORDS = 1350 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 2799 /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "FIPS_PCHANG_2012001_DDR_V01" PRODUCT_VERSION_ID = "V1" PRODUCT_CREATION_TIME = 2012-05-08T23:35:42 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "FIPS_PCHANG_DDR" SOFTWARE_NAME = "mfips_decode_pha.pro" SOFTWARE_VERSION_ID = "1.0" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "FAST IMAGING PLASMA SPECTROMETER" INSTRUMENT_ID = "FIPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-FIPS-DDR-V2.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED FIPS DDR V2.0" SOURCE_PRODUCT_ID = "FileByFile" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" START_TIME = 2012-01-01T00:00:00 STOP_TIME = 2012-01-01T23:59:59 SPACECRAFT_CLOCK_START_COUNT = "233863466" SPACECRAFT_CLOCK_STOP_COUNT = "233949802" ^HEADER = ("FIPS_PCHANG_2012001_DDR_V01.TAB", 1) ^ASCII_TABLE = ("FIPS_PCHANG_2012001_DDR_V01.TAB", 4) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 3 BYTES = 8397 DESCRIPTION = "The first 3 records of this file are the header section. The header contains column headings to improve usability." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 3 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 2799 ROWS = 1350 DESCRIPTION = " This table contains FIPS Flux-Pitch angle histograms." ^STRUCTURE = "FIPS_PCHANG_DDR.FMT" END_OBJECT = ASCII_TABLE END Energy-Resolved Pitch Angle Distributions (ERPCHANG) Label A sample FIPS ERPCHANG DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ FILE_RECORDS = 5 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 16218 /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "FIPS_ERPCHANG_2011174_V1" PRODUCT_VERSION_ID = "1" PRODUCT_CREATION_TIME = 2014-11-06T16:00:00 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "FIPS_ERPCHANG" SOFTWARE_NAME = "MFIPS_DDR_SAMPLE.PRO" SOFTWARE_VERSION_ID = "0.1" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "ENERGETIC PARTICLE AND PLASMA SPECTROMETER" INSTRUMENT_ID = "EPPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-FIPS-DDR-V2.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED FIPS DDR V2.0" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" START_TIME = 2011-06-23T10:45:40.419666 STOP_TIME = 2011-06-23T22:53:43.420605 SPACECRAFT_CLOCK_START_COUNT = "1/217313408.800" SPACECRAFT_CLOCK_STOP_COUNT = "1/217357091.000" ^HEADER = ("FIPS_ERPCHANG_2011174_DDR_V01.TAB", 1) ^ASCII_TABLE = ("FIPS_ERPCHANG_2011174_DDR_V01.TAB", 4) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 3 BYTES = 48654 DESCRIPTION = "The first four records of this file are the header section. The header contains column headings to improve usability." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 7 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 16218 ROWS = 2 DESCRIPTION = " This table contains 2 dimensional pitch angle histograms as described in EPPS DDR SIS." ^STRUCTURE = "FIPS_ERPCHANG_DDR.FMT" END_OBJECT = ASCII_TABLE END FIPS Energy Spectra Label A sample FIPS Energy Spectra DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ FILE_RECORDS = 1350 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 4824 /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "FIPS_ESPEC_2012001_DDR_V01" PRODUCT_VERSION_ID = "V1" PRODUCT_CREATION_TIME = 2012-05-08T23:35:41 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "FIPS_ESPEC_DDR" SOFTWARE_NAME = "mfips_decode_pha.pro" SOFTWARE_VERSION_ID = "1.0" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "FAST IMAGING PLASMA SPECTROMETER" INSTRUMENT_ID = "FIPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-FIPS-DDR-V2.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED FIPS DDR V2.0" SOURCE_PRODUCT_ID = "FileByFile" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" START_TIME = 2012-01-01T00:00:00 STOP_TIME = 2012-01-01T23:59:59 SPACECRAFT_CLOCK_START_COUNT = "233863466" SPACECRAFT_CLOCK_STOP_COUNT = "233949802" ^HEADER = ("FIPS_ESPEC_2012001_DDR_V01.TAB", 1) ^ASCII_TABLE = ("FIPS_ESPEC_2012001_DDR_V01.TAB", 4) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 3 BYTES = 19094472 DESCRIPTION = "The first 3 records of this file are the header section. The header contains column headings to improve usability." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 7 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 4824 ROWS = 1350 DESCRIPTION = " This table contains FIPS energy spectra for selected ion species." ^STRUCTURE = "FIPS_ESPEC_DDR.FMT" END_OBJECT = ASCII_TABLE END FIPS Observed Density Label A sample FIPS Observed Density DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ FILE_RECORDS = 1350 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 216 /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "FIPS_NOBS_2012001_DDR_V01" PRODUCT_VERSION_ID = "V1" PRODUCT_CREATION_TIME = 2012-05-08T23:35:42 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "FIPS_NOBS_DDR" SOFTWARE_NAME = "mfips_decode_pha.pro" SOFTWARE_VERSION_ID = "1.0" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "FAST IMAGING PLASMA SPECTROMETER" INSTRUMENT_ID = "FIPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-FIPS-DDR-V2.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED FIPS DDR V2.0" SOURCE_PRODUCT_ID = "FileByFile" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" START_TIME = 2012-01-01T00:00:00 STOP_TIME = 2012-01-01T23:59:59 SPACECRAFT_CLOCK_START_COUNT = "233863466" SPACECRAFT_CLOCK_STOP_COUNT = "233949802" ^HEADER = ("FIPS_NOBS_2012001_DDR_V01.TAB", 1) ^ASCII_TABLE = ("FIPS_NOBS_2012001_DDR_V01.TAB", 4) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 3 BYTES = 648 DESCRIPTION = "The first 3 records of this file are the header section. The header contains column headings to improve usability." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 20 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 216 ROWS = 1350 DESCRIPTION = " This table contains FIPS differential energy intensities for selected ion species." ^STRUCTURE = "FIPS_NOBS_DDR.FMT" END_OBJECT = ASCII_TABLE END FIPS Arrival Direction Label (Retired Product) A sample FIPS Arrival Direction DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ FILE_RECORDS = 42 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 9158 /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "FIPS_ARRDIR_2012054_DDR_V01" PRODUCT_VERSION_ID = "01" PRODUCT_CREATION_TIME = 2013-06-04T21:22:22 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "FIPS_ARRDIR_DDR" SOFTWARE_NAME = "mfips_ddr_sample.pro" SOFTWARE_VERSION_ID = "0.1" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "FAST IMAGING PLASMA SPECTROMETER" INSTRUMENT_ID = "FIPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-FIPS-DDR-V1.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED FIPS DDR V1.0" SOURCE_PRODUCT_ID = "FileByFile" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" SPACECRAFT_CLOCK_START_COUNT = "1/238523075.000" START_TIME = 2012-02-23T22:20:08.845 SPACECRAFT_CLOCK_STOP_COUNT = "1/238524872.000" STOP_TIME = 2012-02-23T22:50:05.845 ^HEADER = ("FIPS_ARRDIR_2012054_DDR_V01.TAB", 1) ^ASCII_TABLE = ("FIPS_ARRDIR_2012054_DDR_V01.TAB", 4) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 3 BYTES = 9158 DESCRIPTION = "The first three records of this file are the header section. The header contains column headings to improve usability." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 7 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 9158 ROWS = 39 DESCRIPTION = " This table contains FIPS ion flux as a function of arrival direction which have been accumulated in time enough to be meaningfully interpreted." ^STRUCTURE = "FIPS_ARRDIR_DDR.FMT" END_OBJECT = ASCII_TABLE END FIPS Angular Flux Map Label A sample FIPS Angular Flux Map DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ FILE_RECORDS = 5 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 9162 /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "FIPS_FLUXMAP_2011174_V1" PRODUCT_VERSION_ID = "1" PRODUCT_CREATION_TIME = 2014-11-06T16:00:00 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "FIPS_FLUXMAP" SOFTWARE_NAME = "MFIPS_DDR_SAMPLE.PRO" SOFTWARE_VERSION_ID = "0.1" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "ENERGETIC PARTICLE AND PLASMA SPECTROMETER" INSTRUMENT_ID = "EPPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-FIPS-DDR-V2.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED FIPS DDR V2.0" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" START_TIME = 2011-06-23T10:45:40.420458 STOP_TIME = 2011-06-23T22:53:43.420605 SPACECRAFT_CLOCK_START_COUNT = "1/217313408.800" SPACECRAFT_CLOCK_STOP_COUNT = "1/217357091.000" ^HEADER = ("FIPS_FLUXMAP_2011174_DDR_V01.TAB", 1) ^ASCII_TABLE = ("FIPS_FLUXMAP_2011174_DDR_V01.TAB", 4) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 3 BYTES = 27486 DESCRIPTION = "The first four records of this file are the header section. The header contains column headings to improve usability." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 7 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 9162 ROWS = 2 DESCRIPTION = " This table contains angular flux map data as described in EPPS DDR SIS." ^STRUCTURE = "FIPS_FLUXMAP_DDR.FMT" END_OBJECT = ASCII_TABLE END FIPS Kinetic Properties Label A sample FIPS Kinetic Properties DDR file label is shown below: PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ FILE_RECORDS = 42 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 176 /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "FIPS_NTP_2012054_DDR_V01" PRODUCT_VERSION_ID = "01" PRODUCT_CREATION_TIME = 2013-06-04T21:22:22 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "FIPS_NTP_DDR" SOFTWARE_NAME = "mfips_ddr_sample.pro" SOFTWARE_VERSION_ID = "0.1" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "FAST IMAGING PLASMA SPECTROMETER" INSTRUMENT_ID = "FIPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-FIPS-DDR-V2.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED FIPS DDR V2.0" SOURCE_PRODUCT_ID = "FileByFile" MISSION_PHASE_NAME = "MERCURY ORBIT" TARGET_NAME = "MERCURY" SPACECRAFT_CLOCK_START_COUNT = "1/238523075.000" START_TIME = 2012-02-23T22:20:08.845 SPACECRAFT_CLOCK_STOP_COUNT = "1/238524872.000" STOP_TIME = 2012-02-23T22:50:05.845 ^HEADER = ("FIPS_NTP_2012054_DDR_V01.TAB", 1) ^ASCII_TABLE = ("FIPS_NTP_2012054_DDR_V01.TAB", 4) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 3 BYTES = 176 DESCRIPTION = " This table contains FIPS ion number densities and temperatures, as well as the pressure calculated from their product. Quantities are calculated after sufficient time accumulation to allow meaningful interpretation." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 13 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 176 ROWS = 39 DESCRIPTION = " This table contains FIPS NTP values." ^STRUCTURE = "FIPS_NTP_DDR.FMT" END_OBJECT = ASCII_TABLE END FIPS Viewing Normalization Products Labels FIPS Cartesian to MSO Coordinates Rotation Matrix (ROTMSO) PDS_VERSION_ID = "PDS3" /* ** FILE FORMAT ** */ FILE_RECORDS = 1303 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 195 /* ** GENERAL DATA DESCRIPTION PARAMETERS ** */ PRODUCT_ID = "FIPS_ROTMSO_2010001_DDR_V01" PRODUCT_VERSION_ID = "01" PRODUCT_CREATION_TIME = 2014-06-04T10:00:00 PRODUCT_TYPE = "DDR" STANDARD_DATA_PRODUCT_ID = "FIPS_ROTMSO_DDR" SOFTWARE_NAME = "MFIPS_DDR_SAMPLE.PRO" SOFTWARE_VERSION_ID = "0.1" INSTRUMENT_HOST_NAME = "MESSENGER" INSTRUMENT_NAME = "ENERGETIC PARTICLE AND PLASMA SPECTROMETER" INSTRUMENT_ID = "EPPS" DATA_SET_ID = "MESS-E/V/H/SW-EPPS-3-FIPS-DDR-V2.0" DATA_SET_NAME = "MESSENGER E/V/H/SW EPPS CALIBRATED FIPS DDR V2.0" MISSION_PHASE_NAME = "MERCURY 4 CRUISE" TARGET_NAME = "MERCURY" SPACECRAFT_CLOCK_START_COUNT = "1/170791497.000" START_TIME = 2010-01-01T00:00:23.676 SPACECRAFT_CLOCK_STOP_COUNT = "1/170877732.000" STOP_TIME = 2010-01-01T23:57:38.677 ^HEADER = ("FIPS_ROTMSO_2010001_DDR_V01.TAB", 1) ^ASCII_TABLE = ("FIPS_ROTMSO_2010001_DDR_V01.TAB", 4) OBJECT = HEADER HEADER_TYPE = TEXT INTERCHANGE_FORMAT = "ASCII" RECORDS = 3 BYTES = 585 DESCRIPTION = "The first three records of this file are the header section. The header contains column headings to improve usability." END_OBJECT = HEADER OBJECT = ASCII_TABLE COLUMNS = 5 INTERCHANGE_FORMAT = ASCII ROW_BYTES = 195 ROWS = 1300 DESCRIPTION = " This table contains rotation matrix from FIPS cartesian to MSO for each energy scan." ^STRUCTURE = "FIPS_ROTMSO_DDR.FMT" END_OBJECT = ASCII_TABLE END Standards Used in Generating Data Products PDS Standards The EPPS DDR data products are constructed according to the data object concepts developed by the PDS. By adopting the PDS format, the data products are consistent in content and organization with other planetary data collections. In the PDS standard, the DDR data file is grouped into objects with PDS labels describing the objects. Each DDR data product consists of two files: A data file containing an ASCII table object (the primary data), in fixed field format. ASCII table objects are in either comma separated value (CSV) format (EPS) or are whitespace delimited (FIPS). This makes the ASCII data extremely easy to read by many commercial off-the-shelf programs. The one exception is the EPS Pitch Angle Spectrogram, which is a binary PNG file. A label file which serves as a high-level description of the parameters of which correspond to the data file. The label file contains a pointer to an external format file, which details the structure of the table object in the data file. Time Standards One of the time fields in the FIPS table objects references the Mission Elapsed Time (MET). This MET is the spacecraft time in integer seconds that is transmitted to MESSENGER subsystems by the Integrated Electronics Module (IEM). MET = 0 is on August 3, 2004, at 05:59:16 UTC (coordinated universal time), which is 1000 seconds prior to the MESSENGER launch. Relativistic effects and circumstances occurring during the mission would result in MET not being a true account of seconds since launch. Following a planned spacecraft clock reset in early 2013, partition numbers (1/, or 2/) were added to product labels to disambiguate MET seconds after the spacecraft clock reset (if partition number is not present, SPICE defaults to partition 1/). For these reasons the MESSENGER spacecraft clock coefficients file is archived at the PDS NAIF Node. This file is used in conjunction with the leap seconds kernel file in order to calculate the conversion between MET and UTC. The conversion is easily done through the use of SPICE kernels and the CHRONOS Utility. CHRONOS is a utility included with the SPICE package that is distributed by the PDS NAIF node. The SPICE kernels are files that contain the information needed to perform the conversion. Two SPICE kernels are required. One is the Leap Seconds Kernel (LSK) and the other is the MESSENGER Spacecraft Clock Kernel (SCLK). The SCLK file is used by CHRONOS to convert between spacecraft clock time and ephemeris time, while the LSK file is used to convert from ephemeris time to UTC time. The CHRONOS utility is self-documenting and the SPICE package itself contains full documentation on each of the utilities (including CHRONOS) and how they are used. EPPS DDR data is time-tagged with spacecraft event time (SCET) in the following UTC format: CCYY-DDDTHH:MM:SS.sss. This format represents a concatenation of the conventional date and time expressions with the two parts separated by the letter T: CC - century (00-99) YY - year (00-99) DDD - day of year (001-366) T - date/time separator HH - hour (00-23) MM - minute (00-59) SS - second (00-59) sss - fractions of second (000-999) Coordinate Systems There are two coordinate systems in use in the EPPS DDR data products: 1) the Mercury-centric Solar Orbital (MSO, defined in the MESSENGER SPICE Dynamic Frames Kernel) used for spacecraft position vectors; and 2) the FIPS Spherical coordinate system, used for FIPS incident angles since it represents natural coordinates for the sensor. The latter is a spherical version of the FIPS Cartesian coordinate system (FIPS_CART), which is defined in the MESSENGER SPICE Frames Kernel. FIPS Spherical coordinates (FIPS_SPH) consist of a radius (r), zenith angle (theta) and azimuthal angle (phi). The zenith angle is defined as the angle between the vector and the z axis in the FIPS Cartesian coordinate system. It ranges from 0 to 180 degrees. The azimuthal angle ranges from 0 to 360 degrees and is defined as the angle between the vector and the x axis in the FIPS Cartesian coordinate system. The radius is defined as usual as the magnitude of the FIPS Cartesian vector. Data Storage Conventions The data are organized following PDS standards and stored on hard disk at the MESSENGER SOC. The SOC transfers data to PDS as detailed in section 5.3.3. After verification of the data transfer PDS provides public access to MESSENGER science data products through its online data distribution system. Data Validation The EPPS DDR data archive volume set includes all data acquired during the MESSENGER mission. The archive validation procedure described in this section applies to data products generated during all post launch phases of the mission. To be clear, there is one and only one documentation volume and one and only one EPPS data archive volume created over the whole mission. Release dates are stated in the schedule in section 7. Updates to the data volume occurred according to the same schedule. Updates to the documentation volume occurred according to this schedule and at the discretion of the EPPS team. PDS standards recommend that all data included in the formal archive be validated through a peer-review process. This process is designed to ensure that both the data and documentation are of sufficient quality to be useful to future generations of scientists. The process is presented as several steps, most of which occur in the PDS peer review. This peer review is conducted before any volumes are produced and released to PDS. The peer review panel consists of members of the EPPS team, the PPI node of PDS, and at least one outside scientist actively working in the field of energetic particles research. The PDS personnel are responsible for validating that the volumes are fully compliant with PDS standards. The instrument team and outside reviewer(s) are responsible for verifying the content of the data set, the completeness of the documentation, and the usability of the data in its archive format. The peer review validates the documentation and data archive volumes. First the panel reviews this document and verifies that the volumes and DDRs produced to this specification will be useful. The peer review also validates the EPPS DDR data in a two step process. The first step consists of reviewing a sample data set for compliance with the PDS standards. The sample data set is delivered and reviewed in conjunction with delivery and review of this SIS document. The second step is examination of the data to ensure usability and completeness. The PDS personnel are responsible for validating that the DDR data set is fully compliant with PDS standards. The instrument team and the outside science reviewer(s) are responsible for verifying the content of the data set, the completeness of the documentation, and the usability of the data in its archive format. Any deficiencies in the archive data or documentation volumes are recorded as liens against the product by the review panel. The sample data set is created using software provided by APL and the University of Michigan. Once the sample data are validated, and all liens placed against the product or product generation software are resolved, the same software will be used to generate subsequent data products in an automated fashion. During automated production, the data file content is spot checked by members of the EPPS team. "Quick look" products generated by software provided by ACT and the EPPS team are produced routinely and examined by members of the team. In addition, the data are actively used by team members to perform their analysis. Any discrepancies in the data noted during these activities will be investigated. If the discrepancy is a data error, the response depends on the source of the error. If the error is in the software producing the data product, the error is corrected and the data affected is reproduced, replacing the data file. If there is a correctable error in a data file, the file is replaced. If an error in a data file is uncorrectable, the error is described in the cumulative errata file included in the archive volume. The structure of data files and labels will be spot checked by the PPI node for compliance with PDS standards and this SIS. Detailed Data Product Specification Data Product Structure and Organization The MESSENGER EPPS DDR data products are archived at the PDS PPI Node. The automated production and release of DDRs lends itself to the regular release schedule outlined in section 7. If errors are discovered the data are replaced with corrected DDRs on the next scheduled delivery date. Calibration tables and calibration procedures are required to properly analyze DDRs. These ancillary data are archived at the PDS PPI Node as part of the EPPS documentation volume. The documentation volume is referenced by all EPPS data archive volumes. The documentation volume therefore includes the EPPS EDR SIS, the EPPS CDR SIS, and the EPPS DDR SIS in addition to the calibration tables, calibration procedures, and other documents applicable to the data archive volumes. A first release of the EPPS documentation volume accompanied the initial release of the EPPS EDR data archive. An update to the EPPS documentation volume will accompany the initial release of the DDR data archive. After the initial releases of the DDR level documentation there were updates to the documentation volume to document data quality and as needed for product and calibration updates. Handling Errors The possibility exists that errors may be introduced into the archive even with validation procedures applied to the archive volumes. An ERRATA report file is maintained to track and document all discovered uncorrectable errors that may occur during the mission. Correctable errors, such as revised DDRs or DDRs that were missing from a previous PDS delivery are provided at the next scheduled PDS delivery or at the final delivery date (schedule in section 7). PDS then replaces the outdated files with the revised DDR files in the data directories of the archive volume. File revisions are also recorded in the data product label keywords PRODUCT_VERSION_ID and PRODUCT_CREATION_TIME, which can be used in addition to ERRATA.TXT to detect updates. The ERRATA report file is archived in the ROOT directory of the EPPS DDR data volume. Data Format Description Data are stored in ASCII table format. A detached PDS label file provides a detailed description of the structure of each table. Label and Header Descriptions The following are the keyword definitions for the detached PDS label file, which accompanies the instrument data file. The detached PDS label file has the same name as the data file it describes, except for the extension .LBL to distinguish it as a label file. PDS_VERSION_ID Represents the version number of the PDS standards documents that is valid when a data product label is created. PDS3 is used for the MESSENGER data products. FILE_RECORDS Indicates the number of physical file records, including both label records and data records. RECORD_TYPE Indicates the record format of a file. Note: In the PDS, when record_type is used in a detached label file it always describes its corresponding detached data file, not the label file itself. The use of record_type along with other file-related data elements is fully described in the PDS Standards Reference. RECORD_BYTES Indicates the number of bytes in a physical file record, including record terminators and separators. Note: In the PDS, the use of record_bytes, along with other file-related data elements is fully described in the Standards Reference. PRODUCT_ID Represents a permanent, unique identifier assigned to a data product by its producer. PRODUCT_CREATION_TIME Defines the UTC system format time when a product was created. PRODUCT_VERSION_ID Identifies the version of an individual product within a data set. Example: 1.0, 2.0, 3.0. Product_version_id is incremented if a given DDR has to be regenerated and sent to PDS to replace a previously submitted DDR. PRODUCT_TYPE Identifies the type or category of a product within a data set. STANDARD_DATA_PRODUCT_ID Used to link an EPPS DDR file to one of the 12 types of EPPS data products defined within the EPPS DDR SIS. SOFTWARE_NAME Identifies the data processing software used to convert from CDR into DDR products. SOFTWARE_VERSION_ID Indicates the version of the data processing software used to generate the DDR products. MD5_CHECKSUM Used to verify the successful electronic transfer of the DDR from the SOC to the PDS-PPI Node. INSTRUMENT_HOST_NAME The full name of the host on which an instrument is based. In this case it is the MESSENGER spacecraft. INSTRUMENT_NAME Provides the full name of the instrument. INSTRUMENT_ID Provides an abbreviated name or acronym which identifies an instrument. DATA_SET_ID The data_set_id element is a unique alphanumeric identifier for a data set or a data product. The data_set_id value for a given data set or product is constructed according to flight project naming conventions. There is only one data_set_id for the EPPS DDRs. MISSION_PHASE_NAME Provides the commonly used identifier of a mission phase. TARGET_NAME The target_name element identifies a target. The target may be a planet, satellite, ring, region, feature, asteroid or comet. START_TIME Provides the date and time of the beginning of an event or observation (whether it be a spacecraft, ground-based, or system event) in UTC system format. STOP_TIME Provides the date and time of the end of an observation or event (whether it be a spacecraft, ground-based, or system event) in UTC system format. SPACECRAFT_CLOCK_START_COUNT Provides the value of the spacecraft clock at the beginning of a time period of interest. SPACECRAFT_CLOCK_STOP_COUNT Provides the value of the spacecraft clock at the end of a time period of interest. ^TABLE Pointer to the DDR file, which contains the data in ASCII table format. The structure of the data file is defined in a referenced format file. OBJECT Specifies that the DDR is a PDS TABLE object. This object contains its own elements, which are defined below. NOTE: the end of the object definition is always marked with an END_OBJECT line. COLUMNS Identifies the number of columns (fields) in the table. INTERCHANGE_FORMAT This element specifies that the table is in ASCII format. ROW_BYTES Specifies the number of bytes for each row in the table. ROWS Identifies the number of rows (records) in the table. ^STRUCTURE This is a pointer to the external file which provides the structure definition for the table object. The following describes the keywords used to describe the PDS Table Object. These keywords are contained in the FORMAT (.FMT) files for each DDR data product. COLUMN_NUMBER Identifies the location of the column within the larger data object (such as a table). For tables consisting of rows (I= 1, N) and columns (j = 1, M) the column_number is the j-th index of any row. NAME Indicates a literal value representing the common term used to identify an element or object. NOTE: in the PDS data dictionary, name is restricted to 30 characters and must conform to PDS nomenclature standards. BYTES Specifies the number of bytes allocated for this particular column element. DATA_TYPE Specifies the internal representation and/or mathematical properties of the value being stored in this column. START_BYTE Identifies the location of the first byte of the particular column, counting from 1. ITEMS Defines the number of multiple, identical occurrences of a single object. Used mainly in columns containing spectral or histogram data. ITEM_BYTES The size in bytes of individual items in a column. ITEMS * ITEM_BYTES should equal the value in the BYTES column. The format file contains the full text for describing each column of the table. See Appendices for a listing of each field in the individual format files. File Naming Conventions The file names developed for PDS data volumes are restricted to a maximum 36-character file name and a 3-character extension name with a period separating the file and extension names. The general form of the EPPS EPS file name for pitch angle data is "EPSP_AyyyydddDDR_V#.TAB" where EPS Instrument name P_A Pitch Angle yyyy Four digit year ddd Three digit day of year DDR CODMAC processing level V# Version number The general form of the EPPS EPS file name for pitch angle spectrograms is "EPS_PAS_ yyyydddhhmmss_V#.PNG" where EPS Instrument name PAS Select Pitch Angle Spectrogram PASD Daily Pitch Angle Spectrogram yyyy Four digit year ddd Three digit day of year hhmmss Hour, minute, second V# Version number PNG Portable Network Graphics file extension The date in the file name is the start time of the data contained in the file. The general form of the EPPS FIPS file name for DDRs is "FIPS__yyyyddd_DDR_V#.TAB" where FIPS Instrument name Refers to the type of data contained in the file. Possible values are ESPEC - Energy Spectra NOBS - Observed Density PCHANG - Pitch Angle ERPCHANG - Energy-Resolved Pitch Angle ARRDIR - Arrival Direction FLUXMAP - Angular Flux Map NTP - Kinetic Properties ROTMSO - Viewing Normalization rotation matrix to MSO yyyy Four digit year ddd Three digit day of year DDR CODMAC processing level V# Version number For all EPPS data, the initial version number is "V1" (EPS and FIPS_FOVPIX) or "V01" (all other FIPS). The version number increments for each successive version of the DDR product that is produced. A new version of the DDR product may be produced as a result of an error in the product or as a result of errors discovered in the product generation process. For all EPPS data except the EPS Pitch Angle Spectrogram plots: TAB the file extension is dependent on the file type .TAB, EPS and FIPS Instrument Data in ASCII table .LBL, Detached PDS label file EPS Select and Daily Pitch Angle Spectrogram plots: PNG Plots in Portable Network Graphics image format Archive Volume and File Size Two archive volumes are created to archive both the EPPS DDR data and the documentation, which is needed to analyze the DDRs. The first volume is the EPPS Documentation Volume, having volume ID MESSEPPS_DOC. This documentation volume contains products related to the EPPS EDR, CDR, and DDR data archives including: All required PDS catalog files for the EDR, CDR, and DDR archives. The EDR, CDR, and DDR SIS documents. The Space Sciences Review (SSR) instrument paper once copyright permission is obtained. This may not be included in the initial release for copyright reasons. The EPPS calibration report. The EPPS calibration procedures document. Calibration tables. Other documents considered useful by the MESSENGER project or the EPPS team. The data archive volume, designated the EPPS Data Archive Volume and having volume ID MESSEPPS_DDR, contains the DDR data and required files for conforming to PDS volume archive standards. This includes the index files, AAREADME.TXT file, etc. The approximate data archive volume size is 11 GB. Directory Structure and Contents for EPPS Documentation Volume The following illustration shows the directory structure overview for the EPPS documentation volume. ______________________|_____________________ | | | | ______________|_______________ | | | Figure 4 Documentation Volume Structure Directory Contents Directory This is the top-level volume directory. The following are files contained in the root directory. AAREADME.TXT - General information file. Provides users with an overview of the contents and organization of the associated volume, general instructions for its use, and contact information. VOLDESC.CAT - PDS file containing the VOLUME object. This gives a high-level description of the contents of the volume. Information includes: production date, producer name and institution, volume ID, etc. ERRATA.TXT - Text file for identifying and describing errors and/or anomalies found in the current volume, and possibly previous volumes of a set. Any known errors for the associated volume are documented in this file. Directory This contains the calibration tables needed to analyze the EPPS CDR data. The calibration tables are in ASCII format. Format files for the calibration tables are also located here, as are the following files. CALINFO.TXT - Brief description of the directory contents and naming conventions. EPPS_*_EDR2CDR.PDF: Describes the procedure used to convert EDRs to CDRs for each instrument, (as indicated by the * text). FIP*.TAB: The FIPS energy per charge tables. Directory This subdirectory contains the catalog object files for the entire volume. The following files are included in the catalog subdirectory. CATINFO.TXT: Identifies and describes the function of each file in the catalog directory. EPPS*DATASET.CAT: Describes the general content of the EDR data set for each instrument (as indicated by the * text) and includes information about the duration of the mission and the person or group responsible for producing the data. EPPS*DATASET_CDR.CAT: Describes the general content of the CDR data set for each instrument (as indicated by the * text) and includes information about the duration of the mission and the person or group responsible for producing the data. EPPS*DATASET_DDR.CAT: Describes the general content of the DDR data set for each instrument (as indicated by the * text) and includes information about the duration of the mission and the person or group responsible for producing the data. INSTRUMENT.CAT: Describes physical attributes of the EPPS instrument and provides relevant references to published literature. INSTHOST.CAT: Describes the MESSENGER spacecraft. MISSION.CAT: Describes the scientific goals and objectives of the MESSENGER program. It also identifies key people and institutions. PERSON.CAT: Lists and provides contact information for the people involved in the MESSENGER mission, including those involved with EPPS. REF.CAT: Provides references to scientific papers and other publications of interest to those using the data, both for EPPS and the mission as a whole. < DOCUMENT > Directory This subdirectory contains the documentation that is needed in order to understand and analyze the EDR, CDR, and DDR data volumes. The documents are separated into individual subdirectories according to the document type. The document types are not restricted to the four shown in the graphical depiction of the directory structure. There are additional document types as needed to categorize each document. The following file is included in the subdirectory. DOCINFO.TXT: Identifies and describes the function of each file in the DOCUMENT directory. Directory Structure and Contents for EPPS Data Volume ___________________________|____________________________________ | | | | |