ASCAEGCLUS Catalog
Utilizing ASCA archival data of about 300 objects - elliptical galaxies,
groups, and clusters of galaxies - the authors performed systematic
measurements of the X-ray properties of hot gas in their systems, and
compiled them in this study. The steepness (power-law slope) of the
luminosity-temperature (L-T) relation, LX ~ kTalpha, in the range of kT
~ 1.5 - 15 keV is alpha = 3.17 +/- 0.15, consistent with previous
measurements. In the relation, the authors find two breaks at around
intracluster medium (ICM) temperatures of 1 keV and 4 keV: alpha = 2.34 +/-
0.29 above 4 keV, 3.74 +/- 0.32 in the 1.5 to 5 keV range, and 4.03 +/- 1.07
below 1.5 keV. Two such breaks are also evident in the temperature and size
relation. The steepness in the L-T relation at kT > 4 keV is consistent with
the scale-relation derived from the CDM model, indicating that the
gravitational effect is dominant in richer clusters, while poorer clusters
suffer non-gravity effects. The steep L-T relation below 1 keV is mostly
attributed to X-ray faint systems of elliptical galaxies and galaxy groups.
The authors find that the ICM mass within the scaling radius R1500 (the
radius within which the averaged mass density is 1500 times higher than the
critical density) follows the relation of Mgas ~ T(2.33+/-0.07) from
X-ray faint galaxies to rich clusters. Thus, the authors speculate that even
such X-ray faint systems contain large-scale hot gas, which is too faint to
detect.
For this project, the authors utilized all of the ASCA data of elliptical
galaxies and clusters of galaxies. Several clusters were observed more than
once, and they chose the observation with the longest exposure. The total
number of objects that the authors identified as elliptical galaxies and
clusters was 313, and these are listed in this table. Some of the objects
could not be utilized for deriving various correlations, due to either having
an unknown redshift (17 objects), an insignificant detection (13 objects
listed below), or contamination of the environmental X-ray emission, such as
cluster emission around non-cD elliptical galaxies (10 objects: NGC 4472, NGC
4406, NGC 4374, NGC 1404, NGC 499, NGC 6034, NGC 2865, NGC 4291, CL 2236-04
and RX J1031.6-2607). Thus, the authors analyzed the ASCA data for 292
objects, among which were ~ 50 elliptical galaxies and galaxy groups. In this
study, the authors assumed the Hubble constant to be 50 h50 km s-1
Mpc-1 and q0 to be 0.
Table 1 of the reference paper (reproduced below) lists the 13 clusters for
which only 90% confidence level upper limits to the flux in the observer's
frame are available:
Name Flux (0.5 - 2 keV) Upper Limit
(erg/s/cm2)
NGC 5018 9.8 x 1014
GHO 1322+3114 1.3 x 1013
J1888.16CL 5.9 x 1014
CL 0317+1521 4.5 x 1014
MS 1512.4+3647 1.0 x 1012
PRG 38 6.9 x 1014
SCGG 205 6.9 x 1014
RGH 101 9.1 x 1014
3C 184 8.5 x 1014
RX J1756.5+6512 1.6 x 1013
3C 324 5.4 x 1014
PDCS 01 2.8 x 1014
MS 0147.8-3941 5.0 x 1014
ASCAGIS Catalog
This is the complete X-ray source catalog of the ASCA Medium Sensitivity
Survey, AMSS, or the Gas Imaging Spectrometer (GIS) catalog project.
It has been constructed from data for fields covering Galactic latitudes
|b| > 10 degrees which were obtained with the GIS instrument onboard
the ASCA satellite between 1993 May and 1996 December (part I) and between
1997 January and 2000 May (part II). Part I of this catalog (AMSS-I) utilizes
368 combined fields, and contains 1343 sources (including target sources)
with detection significance above 5 sigma in at least one of the 3 survey
bands of 0.7-7.0, 2-10, or 0.7-2.0 keV, while AMSS-II uses 306 fields, and
contains a total of 1190 sources, using the same criteria. The AMSS-I and
AMSS-II catalogs together contain 2533 sources from an area of 278 square
degrees and provide a unique database of X-ray sources in the flux range
of 10^-13 to 10^-11 erg cm^-2 s^-1 (0.7-10 keV). The published paper
contains a summary of the statistical properties of a complete X-ray sample
consisting of 1969 serendipitous sources selected from AMSS-I and AMSS-II.
For each source, the ASCA source name, position, 90% error radius, count
rates (both observed and as corrected for Galactic absorption) in the 3
energy bands, detection signifances and fluxes in the 3 energy bands,
and hardness ratio and associated error are provided.
ASCAGPS Catalog
Sugizaki et al. (2001) have published a study of faint X-ray
sources that were resolved in the ASCA Galactic Plane Survey and
their contribution to the galactic ridge X-ray emission, and the present
database contains their list of discrete sources. The X-ray emission from the
central region of the Galactic plane, |l|<~45 degrees and |b|<~0.4 degrees, was
studied in the 0.7 to 10 keV energy band with a spatial resolution of ~3' with
the Advanced Satellite for Cosmology and Astrophysics (ASCA) observatory.
The authors developed a new analysis method for the ASCA data to resolve
discrete sources from the extended Galactic ridge X-ray emission (GRXE).
Using the ASCA Gas Imaging Spectrometers (GISs), they successfully resolved
163 discrete sources with X-ray fluxes down to 10^-12.5^ergs/cm^2/s and
determined the intensity variations of the GRXE as a function of the Galactic
longitude with a spatial resolution of about 1 degree.
ASCALSS Catalog
The ASCA Large Sky Survey (LSS) was the first wide-area unbiased survey with
the ASCA satellite in the 0.7 - 10 keV band around the North Galactic Pole
region covering a continuous area of 7 square degrees. To make the best use
of ASCA's capabilities, the authors developed a new source detection method
in which the complicated detector responses were fully taken into account.
Applying this method to the entire LSS data independently in the total (0.7 -
7 keV), hard (2 - 10 keV), and soft (0.7 - 2 keV) bands, they detected 107
sources altogether, with sensitivity limits of 6 x 10-14 (0.7 - 7 keV), 1 x
10-13 (2 - 10 keV), and 2 x 10-14 ergs/s/cm2 (0.7 - 2 keV),
respectively. The complete list of detected sources is presented in this
table. The detection criteria that needed to be satisfied were: (i) the
significance of the summed count rate of the GIS and the SIS should exceed
4.5, and (ii) the significance of either the GIS or the SIS should also
exceed 3.5.
ASCAMASTER Catalog
The ASCAMASTER table contains data on all ASCA observations that were
ever in any of the following states: 'Accepted', 'Scheduled Long-Term',
'Scheduled Short-Term', 'Processed', and 'Archived'. The final status of
an observation is given by the parameter Status. Specific dates that affect
the status of an observation are listed as the parameters scheduled_date,
observed_date, processed_date, archived_date, and cycle.
Notice that, if one or more of the date parameters are empty for a given
observation, this means that that those particular processes have not
occurred: e.g., if observed_date is empty, this means that the planned
observation was not observed.
ASCAO Catalog
The ASCAO database contains the listing of accepted targets from all
proposals submitted in repsonse to the ASCA Guest Observer (GO) Announcements
of Opportunities (AOs), as well as the targets that were selected for the
Performance Verification (PV) phase. The current version of ASCAO includes
all accepted targets from AOs 1 through 8.5 inclusive. Notice that, since the
accepted targets include Priority 3 ones of which only a fraction have or will
actually be observed, some of the listed targets in this database will never
have been observed. To obtain more detailed information about the status of
particular targets, please consult either the Master ASCA database table
(ASCAMASTER) or the ASCA Observing Log database table (ASCALOG).
ASCAPRSPEC Catalog
The ASCAPRSPEC table was created for the purpose of providing a complete,
accurate, and easily accessible tracking of ASCA proposal information.
ASCASIS Catalog
This preliminary ASCA SIS Source Catalog contains a list of point sources
detected by the Solid-state Imaging Spectrometers (SIS) on-board the ASCA
Observatory. This catalog was generated by searching for point-like sources
in all data available from the HEASARC's ASCA public archive (ASCAPUBLIC) as
of 24 Oct 1996; and is populated by both target and serendipitous sources in
the SIS field-of-view.
For each catalogued source various information is available, which includes
the celestial coordinates of the source, the count rate, the significance of
detection, and the hardness ratio, total aperture counts, exposure time, and
start time of the observation. In addition, a set of three GIF "thumbnail"
images is available in the broad (0.5 - 12 keV), soft (2 < keV), and hard
(> 2 keV) spectral bands centered on the apparent detection. These images are
convenient for accessing the quality of the source detection.
The current catalog is preliminary, the goal of the catalog authors being to
make the SIS source list available as quickly as possible. To accomplish
this, they took an incremental approach and placed their "work in progress"
on-line, warts and all. They urge caution in using and citing these
preliminary results, as they point out that the information is not, as yet,
100% reliable.
TARTARUS Catalog
The Tartarus database contains the results of a detailed but systematic
analysis of ASCA observations of active galactic nuclei (AGN). It contains
source and background events files, spectra, ancillary response files and
response matrices, images, and assorted light curves for a large number of
ASCA AGN observations. Spectral fit results are done by automatic XSPEC
fitting. This database table allows easy access to reduced AGN data for the
whole community, allowing the maximum scientific return from the data.
Availability of publishable light curves, images, and spectra (which can also
be readily re-fitted) should be particularly valuable to astronomers with
little direct experience in the reduction of X-ray data.
Version 3.1 has been created by analyzing all ASCA observing sequences with
targets designated as AGN, as indicated by a leading "7" in the ASCA
observing sequence number. Version 3.1 contains products for all 611
observing sequences designated as AGN observations. This is a significant
improvement over Versions 1 and 2. Moreover, the 611 sequences for which
products are available are complete in the sense that either the target
object was not detected (in which case an upper limit on GIS2 source counts
is given) or the intended AGN target was detected and the data were fully
analyzed. In order to obtain the most accurate background subtraction and
minimize contamination from any nearby sources, version 3.1 makes more use of
custom extraction regions than previous versions. It is expected that version
3.1 will be replaced when the final ASCA calibration is completed.
