The Ginga archive includes
High level products, such as lightcurves and spectra in FITS
format and accompanying GIF view, and the raw data, which have
been reformatted into FITS. The data are for the Large Proportional Counter
(LAC) experiment and the All-Sky Monitor.
No data are available for the Gamma-Ray detector.
Different groups have contributed to the final LAC Ginga archive. The
University of Leicester generated the LAC source and background spectra
and the source lightcurves, while Penn State University (via an ADP grant)
provided the LAC raw data and the HEASARC provided the LACDUMP.
The Tenma data restoration was included in the same Ginga ADP proposal,
as a possible data set to be done after the completion of Ginga
if resources allow. However the Tenma attitude information was found
to be lost, making this effort not feasible.
Large Area Proportional Counter
All Sky Monitor
There are 6 databases dedicated to Ginga
from which data can be retrieved. High level data (spectra and
lightcurves) and raw data files are available for retrieval. The Ginga database
can be accessed via
Ginga data are located in the
GINGA FTP area
in the HEASARC archive.
A separate restoration effort of the Ginga data was carried out by ISAS in Japan.
During the mission lifetime, at ISAS and other Japanese institutes data and analysis software
resided on a FACOM main-frame computer. The restoration effort approch was not to modify the
original telemetry data structure when porting the data into FITS. This allows a minimum change
to the analysis software which was ported from main-frame computer to a unix enviroment.
The archive of these data and software opened in March 2004 and they are available from
the Japanese Data ARchive and Transfer System, DARTS, at ISAS.
High Level Products :
LACDUMP Spectra and lightcurves were extracted for the pointed target observations
and background observations. To each observation (target or background)
several products were extracted. In particular there are
spectra and lightcurves for the Mid and Top layer.
The lightcurves have been extracted in 4 energy ranges,
2-6, 6-7, 7-17 and 2-17 keV respectively. These products are in FITS and GIF
format. There are also available several plots, in GIF format,
correlations of the HK parameters and there are two sets of response matrices
for the Top and Mid layers. All of the FITS files were produced at
the U. of Leicester in exchange for the ASCA archive.
More information on how these products were extracted from the raw data file
is available in the document
"The Leicester Ginga Databases"
(ps version is located in the
GINGA FTP area
in the HEASARC archive).
All sky monitor Lightcurves for 208 objects were extracted from the
All Sky Monitor data using all detectors. The lightcurves are in three energy bands
(1-6 keV, 6-20 keV and 1-20 keV) and they are stored in a single Fits file with three extensions.
The lightcurve are background subtracted and cover a baseline of about 4.5 years.
For each lightcurve there a GIF file showing the lightcurve in the 1-20 keV energy band.
The HEASARC has two sets of unprocessed (raw) data: the LACDUMP and the
The HEASARC restored into FITS the observation logs from the Ginga
Large Area Counter Array (LACDUMP). Access to these files is
available through the GINGALOG and GINGAMODE databases. A Ginga
of varying numbers of major frames which have lengths of 4, 32, or
128 seconds, depending on the setting of the bitrate. Within each
'observation' several parameters are recorded: the pointing mode,
the on-board computer mode (related to the bitrate), transmission, ra,
dec, magnetic rigidity, the PI (Payload Instrument) counts, the SUD
(Surplus over Upper Discriminator) counts etc. All this information
is available in the log file, where parameters were recorded
on short time scale (4, 32, or 128 seconds) together with
the low count and high counts collected during that time frame
when pointing at a particular part of the sky.
The LACDUMP has now a FITS version. It has been divided in several
FITS files, generated every time one parameter, selected from a subset,
changes. For each FITS file there is also an associated GIF file.
Using these files it is possible to check for transient sources
as in the case of a monitoring instrument. The only difference is that the
sky-coverage is neither uniform nor complete.
First Reduction Files (FRF)
Data received from Ginga were stored in First Reduction Files (FRFs)
which mirror the telemetry stream from the satellite.
Each FRF file corresponds to a period of time when the satellite was
in contact with the ground. Some of the data were telemetered in real
time and other data were telemetered from the bubble memory on board.
Each FRF file can contain data up to 3 different pointing positions.
The raw FITS Ginga data are the FRF files restored in FITS format from
their native format (ADP grant, PI Corbet, at Penn State).
The FITS files were processed from Penn State on a HEASARC machine and
the files directly transferred to the Ginga FTP area at HEASARC.
The FITS files are bintable with 5 extensions containing raw counts
(science data), raw orbital data, raw operational status data,
raw housekeeping data and good time intervals.
The layout of the science data extension consists of several columns
containing counts, stored as an array per row, and one containing time.
The datamode sets the number of channels for the count arrays,
how the signal from each counter is summed (number of columns)
and the integration time.
The GINGARAW database was derived using keywords stored in the
primary header of the FITS file. Each record corresponds to a
different pointing position, therefore it is possible that up to 3
records have associated the same FITS file, but different object name