A3.1 General

A3.1.1 Definition and Purpose of CDF

The Ulysses Common Data File (CDF) is a computer­generated file, processed and reduced to physical parameters to yield a time­ordered record of science data. The set of CDF parameters is directly derived from the telemetry stream, without human intervention, based on algorithms of moderate complexity provided by the investigators and implemented by the Ulysses Data Management Team at JPL. Each parameter is based on data of one specific instrument only. Since relatively simple algorithms are used, the CDF parameters may not be absolutely accurate; in particular, the accuracy may depend on interplanetary conditions or instrument operating modes.

The purpose of the CDF is to provide all investigators with evidence of data trends, significant events, etc., and to permit individual investigators to identify interesting time periods for further detailed analysis and correlative studies.

A3.1.2 Rules for CDF Use

The SWT has agreed on a general policy for the use of the CDF within the Ulysses community. The main purpose of this policy is to ensure the proprietary data rights of the PI and his team (see also Appendix C of this chapter). The key features of this policy are:

• The CDF is to be used for correlative studies only. The CDF is not to be taken as a source of data for detailed analysis.
• Studies that use the data from the CDF should, in general, be conducted in collaboration with the appropriate investigator team.
• No CDF data are to be published without the permission of the appropriate PI.

A3.2.1 CDF Data Channels

The CDF data channels selected by the Ulysses Science Working Team from a number of investigations are listed in Table A3-1.

Table A3.1 Ulysses investigations contributing to the CDF

The data channels included on the CDF tape/CD­ROM are listed in detail in Table A3-2 (below).

Notes for Table A3.2:

1) Spacecraft coordinates. 
2) Applies to 1024 and 512 bps S/C data rate (nominal operations). Resolution becomes 26 min at 256 bps and 52 min at 128 bps. 
3) LET geometrical factor : 0.58 cm2 sr. 
4) HET geometrical factors: H2: 87 cm2 sr; H5: 5.2­3.6 cm2 sr; H8: 16.2­14.9 cm2 sr. 
5) KET geometrical factors: E4: 0.26 cm2 sr; E12: 0.40 cm2 sr.

Table A3.2 Ulysses CDF Data Channels

A3.2.2 CDF Plots

B. E. Goldstein (MS 169­506, JPL) has undertaken to distribute standard plots of selected CDF channels to all PI teams, coinciding with the CDF release by the JPL Ulysses Data Management Team. These standard plots are produced with a scale of 1 cm/day, 16 days per page, i.e., 2 plots per calendar month. The contents of the four types of CDF plots are listed in Table A3-3. Refer to Table A3-2 for details of the parameters plotted.

Table A3.3 CDF plots

A3.3 Reference Documents

Ref. 1: Ulysses Software Interface Specification, Common Data File, SIS2sd; JPL 628­306 dated April 7, 1993. 
Ref. 2: Ulysses Science Data Management Plan, JPL 628­55, Rev. C dated March 1993 
Ref. 3: Ulysses Instruments, Astronomy and Astrophysics Supplement Series, 92, No. 2, 207­440, January 1992.

• Appendix A  PI Comments/Explanations and Caveats
  • Appendix A1   VHM/FGM/HED Experiment
  • Appendix A2   SWOOPS/BAM Experiment
  • Appendix A3   SWICS/GLG Experiment
  • Appendix A4   HISCALE/LAN Experiment
  • Appendix A5   EPAC/KEP Experiment
  • Appendix A6.1 COSPIN/LET/SIM Experiment
  • Appendix A6.2 COSPIN/HET/SIM Experiment
  • Appendix A6.3 COSPIN/KET/SIM Experiment
  • Appendix A7   URAP/STO Experiment
• Appendix B  Acronyms
• Appendix C  Ulysses Agreements on Data Rights

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