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ULYSSES DDS DUST IMPACT DATA

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DATA FILE DESCRIPTION

This table contains Ulysses DDS detector responses and derived quantities as well as spacecraft geometry information for reliable dust impacts. See Gruen et al. (1995a) and Krueger et al. (1999a) for more information.

START_TIME                      = 1990-10-28T13:51                            
STOP_TIME                       = 1995-12-28T01:08                            
PRODUCT_CREATION_TIME           = 1998-11-06                                   
ROWS                            = 1477                                         
COLUMNS                         = 35                                           
RECORD_FORMAT                   = "(i6,1x,i6,1x,a14,1x,f12.4,1x,i1,1x,i1,      
 1x,i3,1x,i2,1x,i2,1x,i2,1x,i2,1x,i2,1x,i2,1x,i1,1x,i1,1x,i2,1x,i2,1x,i1,      
 1x,i1,1x,i1,1x,i1,1x,i1,1x,a1,1x,f7.5,1x,f5.1,1x,f5.1,1x,f7.5,1x,f7.5,     
 1x,i3,1x,i3,1x,i3,1x,f4.1,1x,f4.1,1x,e8.2,1x,f6.1)"                       

ColName Units Start Byte Format Null Value
1 IMPACT SEQUENCE NUMBER - 1 I6 -
2 EVENT SEQUENCE NUMBER - 8 I6 -
3 NATIVE TIME - 15 A14 -
4 JULIAN DATE DAY 30 F12.4 -
5 EVENT CLASS - 43 I1 -
6 ION AMPLITUDE RANGE - 45 I1 -
7 SECTOR - 47 I3 999
8 ION AMPLITUDE CODE - 51 I2 -
9 ELECTRON AMPLITUDE CODE - 54 I2 -
10 CHANNELTRON AMPLITUDE CODE - 57 I2 -
11 ION RISE TIME CODE - 60 I2 -
12 ELECTRON RISE TIME CODE - 63 I2 -
13 ELECTRON ION TIME CODE - 66 I2 -
14 ELECTRON ION COINCIDENCE - 69 I1 -
15 ION CHANNELTRON COINCIDENCE - 71 I1 -
16 ENTRANCE GRID AMPLITUDE CODE - 73 I2 -
17 ENTRANCE GRID RISE TIME CODE - 76 I2 -
18 EVENT DEFINITION - 79 I1 -
19 ION COLLECTOR THRESHOLD - 81 I1 -
20 ELECTRON COLLECTOR THRESHOLD - 83 I1 -
21 CHANNELTRON THRESHOLD - 85 I1 -
22 ENTRANCE GRID THRESHOLD - 87 I1 -
23 CHANNELTRON VOLTAGE LEVEL - 89 A1 -
24 SPACECRAFT-SUN DISTANCE AU 91 F7.5 -
25 ECLIPTIC LONGITUDE DEGREE 99 F5.1 -
26 ECLIPTIC LATITUDE DEGREE 105 F5.1 -
27 SPACECRAFT-EARTH DISTANCE AU 111 F7.5 -
28 SPACECRAFT-JUPITER DISTANCE AU 119 F7.5 -
29 ROTATION ANGLE DEGREE 127 I3 999
30 DETECTOR ECLIPTIC LONGITUDE DEGREE 131 I3 999
31 DETECTOR ECLIPTIC LATITUDE DEGREE 135 I3 999
32 PARTICLE SPEED KILOMETER PER SECOND 139 F4.1 99.9
33 PARTICLE SPEED ERROR FACTOR - 144 F4.1 99.9
34 PARTICLE MASS GRAM 149 E8.2 0
35 PARTICLE MASS ERROR FACTOR - 158 F6.1 9999.9

IMPACT SEQUENCE NUMBER - The number associated with a reliable impact with 1 being the first impact recorded and n being the n'th impact recorded.

EVENT SEQUENCE NUMBER - The number associated with an event in ULYDEVNT.TAB, with 1 being the first event recorded and n being the n'th event recorded.

NATIVE TIME - The time of the event given in year, day of year, hours and minutes in the general form: yyyy-dddThh:mm. See Confidence Level Note, Impact Times.

JULIAN DATE - The full Julian date of the event.

EVENT CLASS - CLASS (CLN) is the event category class which is represented by a single integer ranging from 0 to 3. Class 0 includes all events which are not categorized in a higher class. For classes 1 through 3 the measured parameters and their relation to each other are increasingly restricted, so that CLASS = 3 generally represents dust impact events only. CLASS is determined from ION AMPLITUDE (IA), CHANNELTRON AMPLITUDE (CA), ELECTRON AMPLITUDE (EA), ELECTRON RISE TIME (ET), ION RISE TIME (IT), ION CHANNELTRON COINCIDENCE (IC), ELECTRON ION COINCIDENCE (EI), and noise counters of the electron collector (EN), ion collector (IN), and the channeltron (CN).

                                                                               
   On board qualification scheme.                                              
    Parameters:       class 0      class 1       class 2         class 3       
        EA                                        EA > 0          EA > 0       
        IA             IA > 0       IA > 0        IA > 0          IA > 0       
        CA             CA > 0       CA > 0        CA > 0          CA > 0       
        ET                                     1 <= ET <= 15   1 <= ET <= 15   
        IT                                     1 <= IT <= 15   1 <= IT <= 15   
        IC                                        IC = 0          IC = 0       
        EI                                        EI = 1          EI = 1       
    Noise counter of:                                                          
        EN                                                        EN <= 8      
        IN                                                        IN <= 2      
        CN                                                        CN <= 8      
	

ION AMPLITUDE RANGE - The ION AMPLITUDE RANGE (AR) is the classification of the ION AMPLITUDE value into one of 6 subranges. Each subrange is denoted by an integer between the values of 1 and 6. The six amplitude sub-ranges correspond roughly to a decade of measured electronic charge.

                                                                               
         AR | ION AMPLITUDE                                                    
        ----+--------------                                                    
         1  |     0 - 7                                                        
         2  |     8 - 15                                                       
         3  |    16 - 23                                                       
         4  |    24 - 32                                                       
         5  |    48 - 55                                                       
         6  |    56 - 60                                                       
	 

SECTOR - The angular orientation of the sensor axis about the spacecraft spin axis at the time of each event, measured in the plane perpendicular to the spin axis of Ulysses which points roughly toward the Earth. The angle is defined to be zero when the dust sensor axis looks closest to the Sun, and its value increases counter clockwise when the spacecraft is viewed from Earth. SECTOR is an 8-bit counter having an integer value between 0 and 255, inclusive, and is converted to degrees through scaling by 1.40625. See Confidence Level Note, Sector.

ION AMPLITUDE CODE - An integer code (IA) corresponding to the logarithmic mean of the minimum and maximum range of the bin within which falls the maximum observed signal associated with a single event measured by the ion collector. Conversions to units of coulomb are given in ULYDCODE.TAB. Increasing values indicate increasing amplitudes. Eight digitization steps cover about one decade in charge and steps 32 through 47 are not used. Apparent gaps in the otherwise uniform amplitude sequences occur at steps 16, 17 and 48. These are caused by transitions between different amplifiers.

ELECTRON AMPLITUDE CODE - An integer code (EA) corresponding to the logarithmic mean of the minimum and maximum range of the bin within which falls the maximum observed signal associated with a single event measured by the electron collector. Conversions to units of coulomb are given in ULYDCODE.TAB. Increasing values indicate increasing amplitudes. Eight digitization steps cover about one decade in charge and steps 32 through 47 are not used. Apparent gaps in the otherwise uniform amplitude sequences occur at steps 16, 17, 18 and 48. These are caused by transitions between different amplifiers.

CHANNELTRON AMPLITUDE CODE - An integer code (CA) corresponding to the logarithmic mean of the minimum and maximum range of the bin within which falls the maximum observed signal associated with a single event measured by the channeltron. Conversions to units of coulomb are given in ULYDCODE.TAB. Increasing values indicate increasing amplitudes.

ION RISE TIME CODE - An integer code (IT) corresponding to the logarithmic mean of the minimum and maximum range of the bin within which falls the rise time associated with a single event measured by the ion collector. Conversions to units of micro-seconds are given in ULYDCODE.TAB. Increasing values indicate increasing rise times.

ELECTRON RISE TIME CODE - An integer code (ET) corresponding to the logarithmic mean of the minimum and maximum ranges of the bin within which falls the rise time associated with a single event measured by the electron collector. Conversions to units of micro-seconds are given in ULYDCODE.TAB. Increasing values indicate increasing rise times.

ELECTRON ION TIME CODE - An integer code (EIT) corresponding to the logarithmic mean of the minimum and maximum range of the bin within which falls the difference in time between the start of the electron signal and the start of the ion signal which are associated with a single event. Conversions to units of micro-seconds are given in ULYDCODE.TAB. Increasing values indicate increasing electron minus ion rise time differences.

ELECTRON ION COINCIDENCE - This is an indicator of coincidence of measured negative and positive charge pulses (EIC). The difference in times between the achievement of threshold values for the measured negative and positive charges is determined. If that difference is less than 200 nanoseconds, this variable is set to 1, and 0 otherwise.

ION CHANNELTRON COINCIDENCE - This is an indicator of coincidence of measured channeltron and positive charge pulses (ICC). The difference in times between the achievement of threshold values for the measured channeltron and positive charges is determined. If that difference is less than 200 nanoseconds, this variable is set to 1, and 0 otherwise. See Confidence Level Note, Ion Channeltron Coincidence.

ENTRANCE GRID AMPLITUDE CODE - An integer code (PA) corresponding to the logarithmic mean of the minimum and maximum range of the bin within which falls the maximum observed signal associated with a single event measured by the entrance grid. Conversions to units of coulomb are given in ULYDCODE.TAB. Increasing values indicate increasing amplitudes. See Confidence Level Note, Entrance Grid Amplotude Code.

ENTRANCE GRID RISE TIME CODE - An integer code (PET) corresponding to the logarithmic mean of the minimum and maximum ranges of the bin within which falls the time difference between the entrance grid pulse and the negative charge (electron collector) signal associated with a single event. Conversions to units of micro-seconds are given in ULYDCODE.TAB. Increasing values indicate increasing rise times.

EVENT DEFINITION - The EVENT DEFINITION (EVD) indicates which channels initiates a measuring cycle. The x in each column indicates the channels for which threshold values are exceeded.

                                                                               
        EVD|Q_I Q_E Q_C                                                        
        ---+-----------                                                        
         0 | x   x   x                                                         
         1 | x       x                                                         
         2 |     x   x                                                         
         3 |         x                                                         
         4 | x   x                                                             
         5 | x                                                                 
         6 |     x                                                             
	 

ION COLLECTOR THRESHOLD - Code (ICP) corresponding to the threshold set for the positive ion charge impulse(Q_I) at the time of an event.

                                                                               
        ICP|Q_I (coulomb)                                                      
        ---+----------------                                                   
         0 |   9.0E-15                                                         
         1 |   2.7E-14                                                         
         2 |   6.3E-14                                                         
         3 |   1.6E-13                                                         
	 

ELECTRON COLLECTOR THRESHOLD - Code (ECP) corresponding to the threshold set for the electron charge impulse(Q_E) at the time of an event. See Confidence Level Note, Electron Collector Threshold.

                                                                               
        ECP|Q_E (coulomb)                                                      
        ---+----------------                                                   
         0 |  -8.5E-15                                                         
         1 |  -2.6E-14                                                         
         2 |  -6.0E-14                                                         
         3 |  -1.5E-13                                                         
	 

CHANNELTRON THRESHOLD - Code (CCP) corresponding to the threshold set for the channeltron charge(Q_C) pulse at the time of an event.

                                                                               
        CCP|Q_C (coulomb)                                                      
        ---+----------------                                                   
         0 |  -8.8E-14                                                         
         1 |  -2.6E-13                                                         
         2 |  -5.8E-13                                                         
         3 |  -1.5E-12                                                         
	 

ENTRANCE GRID THRESHOLD - Code (PCP) corresponding to the threshold set for the entrance grid charge pulse(Q_P) at the time of an event separately for positively and negatively charged particles.

                                                                               
        PCP|Q_P (positive) (coulomb)|Q_P (negative) (coulomb)                  
        ---+------------------------+------------------------                  
         0 |         1.4E-14        |        -1.5E-14                          
         1 |         4.3E-14        |        -4.4E-14                          
         2 |         1.0E-13        |        -1.0E-13                          
         3 |         2.6E-13        |        -2.5E-13                          
	 

CHANNELTRON VOLTAGE LEVEL - Code (HV) corresponding to the channeltron high voltage level(HV) set at the time of an event with integers representing fixed voltage differences. See Confidence Level Note, Channeltron Voltage Level.

                                                                               
                 HV|Voltage(Volts)                                             
                 --+-------                                                    
                  ?|  UNKN                                                     
                  X|   OFF                                                     
                  0|   200                                                     
                  1|   900                                                     
                  2|  1020                                                     
                  3|  1140                                                     
                  4|  1250                                                     
		  

SPACECRAFT-SUN DISTANCE - The distance from the spacecraft to the sun.

ECLIPTIC LONGITUDE - The heliocentric ecliptic longitude (Equinox 1950.0) of the spacecraft.

ECLIPTIC LATITUDE - The heliocentric ecliptic latitude (Equinox 1950.0) of the spacecraft.

SPACECRAFT-EARTH DISTANCE - The distance from the spacecraft to Earth.

SPACECRAFT-JUPITER DISTANCE - The distance from the spacecraft to Jupiter.

ROTATION ANGLE - The angular orientation of the sensor axis about the spacecraft spin axis at the time of each event, measured in the plane perpendicular to the spin axis of Ulysses which points roughly toward the Earth. The angle is defined to be zero when the dust sensor axis looks closest to the ecliptic north and it increases as Ulysses rotates positively about its spin axis (by the right hand rule). See Confidence Level Note, Sector.

DETECTOR ECLIPTIC LONGITUDE - The spacecraft-centered ecliptic longitude (Equinox 1950.0) of the sensor axis.

DETECTOR ECLIPTIC LATITUDE - The spacecraft-centered ecliptic latitude (Equinox 1950.0) of the sensor axis.

PARTICLE SPEED - The impact speed of the particle. See Data Reduction, Impact Speed. When no speed can be determined, the value is set to 99.9

PARTICLE SPEED ERROR FACTOR - An upper and lower estimate of impactor speed is obtained by multiplying and dividing, respectively, the particle speed by this factor. When no speed (hence error factor) can be determined, the value of this factor is set to 99.9. See Data Reduction, Impact Speed Error Factor.

PARTICLE MASS - The particle mass. See Data Reduction, Impactor Mass. When the particle is not determined, the mass is not determined and is set to 0.e0.

PARTICLE MASS ERROR FACTOR - An upper and lower estimate of impactor mass is obtained by multiplying and dividing, respectively, the particle mass by this factor. When the speed is not determined, neither is the mass, and this factor is set to 9999.9. See Data Reduction, Impactor Mass Error Factor.