Information for interpreting Galileo DDS codes and flag values in the data files galddust.tab and galdevnt.tab. The values for the codes associated with ION AMPLITUDE, ELECTRON AMPLITUDE, CHANNELTRON AMPLITUDE, ENTRANCE GRID AMPLITUDE, ION RISE TIME, ELECTRON RISE TIME, ELECTRON ION TIME, ENTRANCE GRID RISE TIME, and the particle speeds associated with ION RISE TIME and ELECTRON RISE TIME are to be found in the data file galdcode.tab in the data directory. Further information about the calibration of the instrument may be found in Goller (1988) and in Goller and Grun (1989). A description of the instrument is in the file gddsinst.cat in the catalog directory. 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: ***** Before July 14, 1994: ***** ----------------------------------------------------------------- Parameters: | CLN=0 | CLN=1 | CLN=2 | CLN=3 ----------------------------------------------------------------- IA | IA > 0 | IA > 0 | IA > 0 | IA > 0 --------------| or | or |------------------------------ EA | EA > 0 | EA > 0 | EA > 0 | EA > 0 --------------| or |---------------------------------------- CA | CA > 0 | CA > 0 | CA > 0 | CA > 0 ----------------------------------------------------------------- ET | | | 1 <= ET <= 15 | 1 <= ET <= 15 ----------------------------------------------------------------- IT | | | 1 <= IT <= 15 | 1 <= IT <= 15 ----------------------------------------------------------------- EIC | | | EIC = 0 | EIC = 0 ----------------------------------------------------------------- ICC | | | ICC = 1 | ICC = 1 ----------------------------------------------------------------- Noise counter| | | | of: | | | | EN | | | | EN <= 8 IN | | | | IN <= 2 CN | | | | CN <= 8 ----------------------------------------------------------------- ***** After July 14, 1994: ***** Note: Classes 1 and 2 are divided into two different subclasses which are mutually exclusive. ------------------------------------------------------------------------ Parameters: | CLN=0 | CLN=1 | CLN=2 | CLN=3 ------------------------------------------------------------------------ IA | IA>0 | IA>0 | IA>0 | IA>0 | IA>0 | IA>0 --------------| or |--------|------|------------|--------|----------- EA | EA>0 | EA>0 | | EA>0 | | EA>0 --------------| or |--------|------|------------|--------|----------- CA | CA>0 | | CA>0 | | CA>0 | CA>0 --------------|-------|--------|------|------------|--------|----------- ET | | | | | | 1<=ET<=15 --------------|-------|--------|------|------------|--------|----------- IT | | | | | | 1<=IT<=15 --------------|-------|--------|------|------------|--------|----------- EIC | | EIC=1 | | EIC=0 | | EIC=0 --------------|-------|--------|------|------------|--------|----------- ICC | | | | | ICC=1 | ICC=1 --------------|-------|--------|------|------------|--------|----------- | | EIT=0 | | | | EIT | | or | | 3<=EIT<=15 | | 3<=EIT<=15 | | EIT=15 | | | | --------------|-------|--------|------|------------|--------|----------- Noise counter| | | | | | of: | | | | | | EN | | | | EN<=8 | | EN<=8 IN | | | | IN<=14 | | IN<=2 CN | | | | | CN<=14 | CN<=2 ------------------------------------------------------------------------ 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 EVENT DEFINITION The EVENT DEFINITION (EVD) indicates which channels initiate a measuring cycle. The x in each column indicates the channels for which threshold values must be 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) arising from an event. ICP|Q_I (coulomb) ---+---------------- 0 | 1.0E-14 1 | 2.6E-14 2 | 5.8E-14 3 | 1.5E-13 ELECTRON COLLECTOR THRESHOLD Code (ECP) corresponding to the threshold set for the electron charge impulse (Q_E) arising from an event. ECP|Q_E (coulomb) ---+---------------- 0 | -9.8E-15 1 | -2.4E-14 2 | -5.5E-14 3 | -1.4E-13 CHANNELTRON THRESHOLD Code (CCP) corresponding to the threshold set for the channeltron charge impulse (Q_C) arising from an event. CCP|Q_C (coulomb) ---+---------------- 0 | -1.8E-13 1 | -2.4E-13 2 | -5.2E-13 3 | -1.2E-12 ENTRANCE GRID THRESHOLD Code (PCP) corresponding to the threshold set for the entrance grid charge pulse(Q_P) arising from an event separately for positively and negatively charged particles. PCP|Q_P (positive) (coulomb)|Q_P (negative) (coulomb) ---+------------------------+------------------------ 0 | 9.4E-15 | -1.8E-14 1 | 2.3E-14 | -3.8E-14 2 | 5.0E-13 | -7.3E-14 3 | 1.2E-13 | -1.5E-13 CHANNELTRON VOLTAGE LEVEL Code (HV) corresponding to the channeltron high voltage level set at the time of an event with integers representing fixed voltage differences. See Confidence Level Note, Channeltron Voltage Level, in GALD.CAT. HV|Voltage(Volts) --+------- ?| UNKN X| OFF 0| 200 1| 900 2| 1020 3| 1140 4| 1250 ---------------------------------------------------------