Ginga Data
Only the LAC data are archived at present. They are archived in a target-oriented (strictly speaking, observation-oriented) structure, i.e., the data covering a sequent observation between two maneuvers (changes of satellite attitude, including "slews") is put into a directory. There are two types of observations, a target observation and a background (blank sky) observation.
Each dataset includes telemetry data (First Reduction File =FRF) and summary lists of the LAC housekeeping and attitude information (LACDUMP files). For a target observation, those of "recommended" background data are also provided. Files are put in the directories listed below. Each FRF is made per one satellite-operation pass (a contact or remote pass), while LACDUMP is per one day. These files are NOT divided at the times of maneuvers and therefore may contain data of previous and/or next targets as well as those during maneuvers.
| frf/ | Telemetry files (FRFs; Wrapped FITS files) |
|---|---|
| lacdump/ | LACDUMP files (ASCII files) |
| frf_bgd/ | Telemetry files for recommended background data |
| lacdump_bgd/ | LACDUMP files for recommended background data |
The recommended background data are simply selected from all the blank sky observations performed within 3 days. Before using them, however, users are strongly advised to check if they are really applicable for background subtraction in each case. (Or you can search for appropriate background data utilizing the DARTS searching system; check the "Pattern Match" check-box, and enter "BGD" for the "TARGET_NAME" pattern. Note that background data are not necessary if you only use the "Hayashida-method" for background subtraction. For details see Chapter 5 of the ABC manual.)
The history file of the high-voltage (HV) level, the Coarse Gain, and the Fine Gain is provided, where the most frequent HV and Gain status is shown for each FRF.