File: P10TRDHR_FMT.txt Version: NSSDC 02/27/2009 -------------------------------------------------------------------------- PIONEER 10 TRAPPED RADIATION DETECTOR (TRD) EXPERIMENT: HOURLY AVERAGED INTERPLANETARY COSMIC RAY DATA, 1972-1993 Principal Investigator: Dr. Walker Fillius CASS 0111 University of California - San Diego Dates: 1972-03-03 to 1993-11-02 Data Set Description: Four TRD data channels are given for response to high energy cosmic ray protons and Z>1 ions. The counting rates are calculated as one-hour averages from original dataset records at thirty-minute intervals. Times are given as Spacecraft Event Time - UT (SCET-UT). The NSSDC ID for the source data set was 72-012A-05G. This version of the hourly resolution data set was created in 2008 from a predecessor version to better support the FTPBrowser interface at http://ftpbrowser.gsfc.nasa.gov/p10_part_trd_1h.html. It differs from its predecessor in the following respects: (a) the new data set has annual files while the predecessor had 6-month files (b) the fill value was changed from -1.00E+31 to 1.00E+031 (c) there is a record for every hour in the new data set, even if there are no TRD data. (d) month and day-of-month have been replaced by day-of year. The 6-month files of the predecessor hourly data set are at ftp://nssdcftp.gsfc.nasa.gov/spacecraft_data/pioneer/pioneer10/particle /trd/ip_1hour_ascii/old/ Parameter Description: IYR Year (4 digits) IDY Day of Month IHR Hour of Day TBR Code for Telemetry Bit Rate [bits/second = 2**(3+TBR)] TDF Telemetry Data Format (A, A/D, B, B/D) M3L 80-300 MeV Protons (50%)and >80 MeV/n Z>1 Ions [counts/second] M1L >80 MeV/n Protons (90%) and Z>1 Ions [counts/second] C1 >480 MeV/n Protons (80%)and Z>1 Ions [counts/second] C3 >650 MeV/n Protons and Z>1 Ions (70%) [counts/second] RAD Radial distance of spacecraft from Sun [AU] Parameter Format: The FORTRAN code READTRD reads summary data files from the Pioneer 10 and 11 TRD experiments in 30-minute averages and outputs one-hour averages weighted by the number of samples in each 30-minute data record. The output WRITE statement for the one-hour records in COHO is as follows: WRITE(20,320) IYROUT,IDYOUT,IHROUT,TBR,TDF,RM3L, * RM1L,RC1,RC3,XRADIS 320 FORMAT(I4,14,I3,1x,A3,4E12.4,F8.3) Related Information and Data: Further details on the experiment can be found at ftp://nssdcftp.gsfc.nasa.gov/spacecraft_data/pioneer/pioneer10/particle/ trd/ip_30min_ascii/p10trd_voldesc.sfdu. This reference, plus ftp://nssdcftp.gsfc.nasa.gov/spacecraft_data/pioneer/ pioneer10/particle/trd/ip_30min_ascii/p10trd_voldesc.sfdu contain details on the 30-min data set from which the hourly count rates were produced. Hour averages of the interplanetary solar wind data from, and hourly heliocentric coordinates of, Pioneer 10/11 and other interplanetary spacecraft may be also be accessed and plotted on-line through the COHOWeb service based at the same WWW site as above. Acknowledgement: Use of these data in publications should be accompanied at minimum by acknowledgements of the National Space Science Data Center and the responsible Principal Investigator defined in the experiment documentation provided here.