PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 2007-06-01 NOTE = "AAREADME.TXT describes this archive product." END_OBJECT = TEXT END Volume VGPW_0201 Voyager 1 and 2 Electron Plasma Density and Characteristic Plasma Frequencies PWS Data Archive Jupiter Flyby Planetary Plasma Interactions Discipline Node of the Planetary Data System ======================================================================== Introduction ======================================================================== This volume set is comprised of two separate data sets containing density measurements within the outer Jovian magnetosphere (outside ~20Rj) determined from Voyager 1 and Voyager 2 spacecraft. By measuring characteristic frequencies of the plasma from high-resolution wideband plasma wave spectrum data and using the equations of cold plasma theory, the density was determined. Every effort has been made to assure that the data and documentation are of the best possible quality. However, mistakes are inevitable. The PPI Node of the PDS will maintain an online list of ERRATA where errors and updates are documented. Should any user of this product find an error on this volume, please report the error to the PPI Node so that the finding can be made public. All users are encouraged to verify the "correctness" of the data prior to submitting any publications or other work based on these data. Users of these data are encouraged to acknowledge both the PDS and the principal investigators of the instruments whose data is used in analysis in all publications. ======================================================================== Quick Start Summary ======================================================================== This volume, VGPW_0201, contains density measurements derived from high-resolution wideband plasma wave spectrum data taken during both Voyager 1 and 2 missions during their Jupiter flybys. This volume separates the data into Voyager 1 and Voyager 2 directories with individual day-long files in each. The Voyager 1 directory includes all available density data for Voyager 1 spacecraft event time(SCET) 1979-03-01 through 1979-03-21. The Voyager 2 directory includes all available density data for Voyager 2 spacecraft event time (SCET) 1979-07-04 to 1979-07-11. The density data has been determined from plasma wave freqeuncy measurements taken from Voyager high-resolution spectrum data. Included with the electron plasma density data are parameters utilized in determining the density such as the frequencies of the plasma (including frequencies measured directly from the PWS spectrum and frequencies calculated using magnetic field data and the equations of cold plasma theory), and the coordinates in both Jupiter Solar Ecliptic (JSE) and Jovigraphic coordinate systems, to ensure full replicability. ======================================================================== Related PDS Products ======================================================================== All density measurements were derived from measuring characteristic frequencies from Voyager's high-resolution wideband plasma wave spectrum data. The spectrum data is in frequency vs. time spectrograms which extend from approximately 28 Hz up to 12 kHz. The high-resolution waveform data has been extensively compiled and submitted to the PDS under the following data set IDs: VG1-J/S/SS-PWS-1-EDR-WFRM-60MS-V1.0 VG2-J/S/U/N/SS-PWS-1-EDR-WFRM-60MS-V1.0 They are available elsewhere within the Planetary Data System on volume sets VGPW_10xx (Voyager 1) and VGPW_20xx (Voyager 2). Magnetic field data used in this volume were obtained from the Voyager 1 and 2 magnetometer data which has been submitted to the PDS under the following data set IDs: VG1-J-MAG-4-SUMM-HGCOORDS-1.92SEC-V1.0 VG2-J-MAG-4-RDR-HGCOORDS-1.92SEC-V1.0 They are available elsewhere within the Planetary Data System on volumes VG_1501 (Voyager 1) and VG_1502 (Voyager 2). ======================================================================== Volume Set Information ======================================================================== This volume, VGPW_0201, contains all available density ASCII data as derived from Voyager 1 and 2 high-resolution wideband plasma wave spectrum data from the spacecraft event time (SCET) interval 1979-03-01 through 1979-07-11. This volume will be updated only if the improvement of temporal or spectral measurement resolution becomes significant. ======================================================================== Volume Format Information ======================================================================== The disk is organized into a hierarchical directory structure. The disk is formatted according to a combination of ISO 9660, UDF, Rock Ridge (UNIX), and Joliet (Microsoft) standards in order to accommodate users on a wide variety of platforms. This volume does not contain any Extended Attribute Records (XAR). Thus, VMS users may have some problems accessing files on this volume. ======================================================================== File Formats ======================================================================== The data files on this volume are .CSV files. Browse data are provided in Portable Network Graphics (PNG) format. All data files are described by detached PDS labels. A detached label file has the same name as the data file that it describes, but with the extension .LBL. For example, the file V11979060.CSV is accompanied by the detached label file V11979060.LBL in the same directory. File names within this archive comply with the "27.3" convention for compliance with ISO 9660 Level 2 interchange requirements. All documents, detached PDS labels, and HTML files are stream format files, with a carriage return (ASCII 13) and a line feed character (ASCII 10) at the end of the record. This allows the files to be read by MacOS, MS Windows, UNIX, and VMS operating systems. UNIX system users will see an unnecessary carriage return character (^M) at the end of each line. Mac users will see an unnecessary line feed character (^J) at the start of each line. ASCII tabular data files (.TAB) are formatted so that they may be read directly into many database management systems (DBMS) or spreadsheet programs on various computers. All fields are of fixed length and are separated by white space or commas. Character fields are left justified, and numeric fields are right justified. The records are of fixed length, and the last two bytes of each record contain the ASCII carriage return and line feed characters. This allows a table to be treated as a fixed length record file on computers that support this file type and as a normal text file on other computers. The document, PDS label, and ASCII spreadsheet files on this volume can be viewed with a Web browser. Note that to view these files, the browser may need to be configured to recognize files with extensions of .CAT, .LBL, and .TAB as text files. Users with Web browsers also can navigate the disk via the HTML file AAREADME.HTM in the disk's root directory. PDS labels are object-oriented. The object to which the label refers (e.g., SERIES, TABLE, etc.) is denoted by a statement of the form: ^object = location in which the caret character (^, also called a pointer in this context) indicates that the object starts at the given location. For an object in the same file as the label, the location is an integer representing the starting record number or byte of the object (the first record/byte in the file is 1). For an object located outside the label file, the location denotes the name of the file containing the object, along with the starting record or byte number. For example: ^SERIES = ("20903684.DAT", 3) indicates that the SERIES object begins at record 3 of the file 20903684.DAT, in the same directory as the detached label file. Below is a list of the possible formats that use the ^object keyword. ^object = n ^object = n ^object = ("filename.ext",n) ^object = ("filename.ext",n) where n is the starting record or byte number of the object, counting from the beginning of the file (record 1, byte 1); default is record number. indicates that number given is in units of bytes. filename upper-case file name. ext upper-case file extension. In cases where many files of the same format or structure are present, the structure description component is detached from the primary label. This minimizes repeating information which does not vary from file to file. In these cases, a format file (.FMT) contains the file structure information and the base label (.LBL) describes the parameters which generally do vary from file to file (number of records, file name, start/stop time, etc.). When a format file is used within the PDS label, the syntax is: ^STRUCTURE = filename Example: ^STRUCTURE = "SPREADSHEET.FMT" Syntactically, the contents of the format file can be inserted directly into the base label such that the entire file contents replace the single line ^STRUCTURE = filename. ======================================================================== Errata ======================================================================== There is a file called ERRATA.TXT found at the root level of this volume which contains a list of known deficiencies or caveats associated with data on this volume at the time this DVD-R was published. Any changes or errors that are found after the production of this volume can be found on the PPI Node errata Web page, http://www.igpp.ucla.edu/cgi-bin/ditdos?errata=VGPW_0201. If you find an error on this disk, please report the error to the PDS Operator at the PPI Node of the PDS. Internet pds_operator@igpp.ucla.edu Telephone (310) 206-6073 U.S. Mail PDS Operator c/o Dr. Raymond Walker UCLA - IGPP Los Angeles, CA 90095-1567 Only through support and feedback of the users of these data can an effective errata list be maintained. ======================================================================== Software ======================================================================== Complete display and analysis Java applications as well as the algorithm used to measure spectral peaks and cutoffs are provided in the EXTRAS/SOFTWARE directory. This software is provided as "as is" and is distributed as a service to the community. More information is provided in the file EXTRAS/EXTRINFO.TXT. ======================================================================== Volume Contents and Structure ======================================================================== This section describes the volume structure and naming conventions. Below is a tree diagram of the volume, followed by a description of the directory function and key files in each directory. [VGPW_0201] Root directory | |- AAREADME.TXT Describes volume contents, organization, | and use (this file). | |- AAREADME.LBL Label file for AAREADME.HTM | |- AAREADME.HTM HTML version of AAREADME.TXT. Can be | viewed in a web browser and used to | navigate the volume. | |- ERRATA.TXT Describes known deficiencies or caveats in | the data or volume set. | |- VOLDESC.CAT High-level description of volume contents. | |- [BROWSE] Contains browse summary plots in PNG format. | |- [CATALOG] Information on data sets and how they are | processed and produced. Also contains | information regarding Voyager 1 and 2, the | instrument covered by this volume, | personnel involved, and references. | |- [DATA] Contains all data in a branching tree | structure of subdirectories. | |- [DOCUMENT] Contains documents describing the data on | the volume. | |- [EXTRAS] Contains files which facilitate use of the | disk, but which are not required for such | use. These files include an HTML graphical | data browser index, example software code | for reading the data, and a full-featured | analysis application. | |- [INDEX] Contains an index of PDS label files for all data archived on this volume and on the volume set to date. ======================================================================== Driver and Hardware Information ======================================================================== This disk has been formatted according to a combination of ISO 9660 level 2, Rock Ridge (UNIX), Joliet (Microsoft), and UDF standards. It has been recorded on DVD-R media and should be readable on all major computing platforms hosting DVD readers. ======================================================================== Contacts ======================================================================== The people most directly responsible for the construction and release of this volume are Chris Piker and William Kurth from the University of Iowa. Dr. William S. Kurth is responsible for the construction of the data set and has provided support for all aspects of this volume's release. For questions or problems regarding this volume, please contact the PDS/PPI PDS operator: Internet pds_operator@igpp.ucla.edu Telephone (310) 206-6073 PDS Operator c/o Dr. Raymond Walker U.S. Mail 3845 Slichter Hall UCLA - IGPP Los Angeles, CA 90095-1567 For questions regarding PDS Standards or other volumes available from the PDS, please contact PDS Operator at the PDS Central Node (at JPL): Internet pds_operator@jpl.nasa.gov Telephone (818) 354-4321 Planetary Data System, PDS Operator Jet Propulsion Laboratory U.S. Mail Mail Stop 202-101 4800 Oak Grove Dr. Pasadena, CA 91109-8099 The PDS and the Planetary Plasma Interactions (PPI) Node in particular, assume no legal liability for errors on this disk. All users are encouraged to verify the "correctness" of the data prior to submitting any publications or other work based on these data. Errors on this disk should be reported back to the PPI Node of the PDS through the ERRATA reporting procedures described above. ======================================================================= Disclaimer ======================================================================= The PDS and the Planetary Plasma Interactions (PPI) Node in particular, assume no legal liability for errors on this disk. All users are encouraged to verify the "correctness" of the data prior to submitting any publications or other work based on these data. Errors on this disk should be reported back to the PPI Node of the PDS through the ERRATA reporting procedures described above. All trademarks are acknowledged as the property of their respective owners. The producers and publishers of this archive do not endorse any commercial entities which may be mentioned for clarity. ======================================================================= Acknowledgements ======================================================================= These data were collected under the auspices of the Voyager Project. Donald A. Gurnett was the Plasma Wave Spectrometer Principal Investigator. William S. Kurth was responsible for the creation of the density data set and has played a primary role in virtually all processes associated with this volume. The archiving effort at The University of Iowa was supported by C. Piker, J.B. Groene, and B.L. Barnhart. Java software was developed by J.B. Faden and E. West. This archiving effort was supported by the Planetary Plasma Interactions Node of the Planetary Data System. ========================================================================