The HEASARC Online Service
The HEASARC currently has over 90 databases available for BROWSing within the Online Service. The following is the listing of SYSTEM databases:
Name Description Observatory
Recent additions to the HEASARC Online Service
ASCAO - ASCA Accepted AO Proposals
The ASCAO database contains the listing of accepted proposals for ASCA AO1 as well as targets from the PV phase.
ASCALTL - ASCA Long-term Timeline
The ASCALTL database contains the long-term timeline for the ASCA (Advanced Satellite for Cosmology and Astrophysics) satellite.
VELA5B - Vela 5B Database
The VELA5B database contains FITS data products files. Data for these sources were obtained from the Vela 5B all-sky XC detector.
The Vela 5B nuclear test detection satellite was part of a program run jointly by the Advanced Research Projects of the U.S. Department of Defense and the U.S. Atomic Energy Commission, managed by the U.S. Air Force. It was placed in a nearly circular orbit at a geocentric distance of ~118,000 km on 23 May 1969; the orbital period was ~112 hours. The satellite rotated about its spin axis with a ~64-sec period. The X-ray detector was located ~90 degrees from the spin axis, and so covered the celestial sphere twice per satellite orbit. Data were telemetered in 1-sec count accumulations. Vela 5B operated until 19 June 1979, although telemetry tracking was poor after mid-1976.
One important detector performance characteristic which affects the Vela 5B data is a gain variation due to a ~60 deg C satellite temperature change from one side of the orbit to the other. If the data for a source were taken when the satellite was at one of its temperature extremes, a profound modulation is introduced into the count rate at the 56-hour timescale between observation sequences of the source. Additionally, the amplitude of the effect is modulated by the ~300-day precession period of the Vela 5B orbit. Lack of pre-launch testing precludes any quantitative post-launch compensation. A temperature time history is available to HEASARC users in a FITS file (VELA_TEMP) so that they may check any suspicious source data against the known times of temperature extremes.
The time history of the Crab detected flux decreased by ~15% between 1969 and 1979. It is believed that this decrease is due to a gain change in the XC detector as it aged. No attempt to correct for this trend has been made in the data processing. Users who desire to do so, or who want to express detected source intensities in units of crabs, will have to access the FITS file containing the Crab data to extract the necessary information.
ROSGHRI - ROSAT German HRI Public REV0 Data
The ROSGHRI database contains the list of German ROSAT HRI observations for which REV0 data are publicly available. The database is updated weekly, as new datasets are released for public use and are ingested into the archive. ROSGHRI also includes a list of all data which have been distributed to the PI and are not yet public.
(ROSGHRI also includes a list of all data which have been distributed to the PI and are not yet public; to see this information, switch to the TOTAL sample with the BROWSE command csam total.)
For each observation listed in ROSGHRI, the target name and coordinates are given, as well as the ROSAT observation request number (ROR), actual and requested exposure times, date the observation took place, date data were distributed to the PI, date data will become public, and more.
ROSGPSPC - ROSAT German PSPC Public REV0 Data
The ROSGPSPC database contains the list of German ROSAT PSPC observations for which REV0 data are publicly available. The database is updated weekly, or as new datasets are released for public use and are ingested into the archive.
(ROSGPSPC also includes a list of all data which have been distributed to the PI and are not yet public; to see this information, switch to the TOTAL sample with the BROWSE command csam total.)
For each observation listed in ROSGPSPC, the target name and coordinates are given, as well as the ROSAT observation request number (ROR), actual and requested exposure times, date the observation took place, date data were distributed to the PI, date data will become public, and more.
CVCAT - General Catalogue of Variable Stars
The CVCAT database is the General Catalog of Variable Stars. This catalog contains information necessary for obtaining observations of variable stars and, in particular, cataclysmic variables.
XRBCAT - X-Ray Binaries Catalog
The XRBCAT database is a compilation from several sources of X-ray binaries.
PKSCAT90 - Parkes Southern Radio Source Catalog
PKSCAT90 is the Parkes Catalog (1990) which consists of radio and optical data for 8264 radio sources. It covers essentially all the sky south of declination +27 degrees but largely excludes the Galactic Plane and the Magellanic Cloud regions.
The original Parkes Radio Catalogue was compiled from major radio surveys with the Parkes radio telescope at frequencies of 408 MHz and 2700 MHz. This work spanned a period of nearly 20 years and was undertaken largely by John Bolton and his colleagues. Since then, improved positions, optical identifications, and redshifts have been obtained for many of the sources in the Catalogue. Furthermore, flux densities at several frequencies have supplemented the original surveys so that the measurements now cover the frequency range 80-22,000 MHz. However, coverage at the highest frequencies is still sparse.
Important contributions to the usefulness of the Catalogue have been radio data from the Molonglo 408 MHz survey and the 80 MHz Culgoora measurements of Slee et al. PKSCAT90 should thus be regarded as a compendium of radio and optical data about southern radio sources. However, at the moment, it contains only sources originally found in the Parkes 2700 MHz Survey (see e.g. Part 14, Bolton et al, 1979, Aust J Phys, Astrophys Suppl, No. 46 and references therein).
The original radio survey data of the Catalogue and the optical identifications have been published in a series of papers in the Australian Journal of Physics (see above reference). The associated optical spectral data on which redshifts were obtained has also been published, mainly in the Astrophysical Journal and Monthly Notices of the Royal Astronomical Society.
Users should note that the sky zone between -4 and +4 degrees has been the subject of a re-survey and is now complete to 0.25 Jy.
Newly Revised and Updated HEASARC Databases
The ROSAT Archives
The following ROSAT databases continue to be updated as necessary:
ROSSTL - ROSAT Short-term Timeline
The ROSSTL database is based on the ROSAT short term timeline. This is generated by MPE approximately one week in advance of observations, and is incorporated into the database (via the UKDC) accordingly. It contains details of all scheduled pointed observations on a one entry per slot basis, where a "slot" is an interval of constant celestial pointing with detector HTs switched on.
ROSATLOG - ROSAT Log of Observations
The ROSATLOG database has been created for the purpose of providing a complete, accurate and easily accessible record of ROSAT observations.
ROSATLOG is made by cross-correlating ROSAT observation records with the short-term timeline, and contains information about all pointings executed by the satellite during the performance verification (PV) and AO phases. For each observation, details are given concerning target name and coordinates, pointing start and stop times, PI name and country, ROSAT Observation Request sequence number, and more.
ROSATLOG is periodically updated, as new short-term timelines and observation records are generated at the German ROSAT Science Data Center at the Max Planck Institute for Extraterrestrial Physics (MPE), and sent to the ROSAT Guest Observer Facility at Goddard Space Flight Center (GSFC).
The ROSATLOG database has been made as accurate a record of ROSAT pointings as is possible with the available information. The primary source of information for the database is ASCII files dumped from a database at MPE. These ASCII files contain information originally extracted from the attitude protocol files, which are daily-generated files containing coordinate and time values for each day's ROSAT pointing. Errors in the information extracted from the attitude protocol files are weeded out and corrected in the database at MPE as necessary, and the final versions of the ASCII files are output and sent to the ROSAT GOF at GSFC, to be used as the basis for the ROSATLOG database.
Each observation listed in the MPE ASCII files has a ROSAT Observation Request (ROR) sequence number associated with it. Using this sequence number, the observation is matched with the corresponding entry in the ROSAT short-term timeline. (The short-term timeline is also generated by MPE, approximately one week in advance of observations. It is available online within the HEASARC database system, as a database called ROSSTL.) Information such as PI name, country, target name and number, primary instrument, solar angle, time constraints, etc., is then extracted from the timeline and put into the ROSATLOG database. (NOTE: Typing the BROWSE command lparm will display all the ROSATLOG parameter names and one-line descriptions to the screen. Those parameters with an asterisk at the beginning of their descriptions are parameters whose values come from the ROSAT short-term timeline; parameters without asterisks contain values extracted from the MPE ASCII files.)
Certain ROSATLOG entries may have parameter fields which contain 0.0, 999.99, 9999, ??, or UNKNOWN. In these cases, either the ROR was not found in the short-term timeline, or the ROR was found but the completed observation could not be matched with one of the planned observations listed in the short-term timeline.
Despite efforts to make ROSATLOG a complete and accurate record of ROSAT pointings, some errors may still appear; thus ROSATLOG should be used only as a basic guide to what pointings have been executed. ROSATLOG shows in which direction ROSAT pointed, and at what time. HOWEVER, it does NOT reflect problems which may have occurred during the pointing, and which can result in the total exposure time being much less than the duration of the pointing.
ROSPUBLIC - ROSAT US Distributed REV0 Data
ROSUSPSPC - ROSAT US PSPC Public REV0 Data
ROSUSHRI - ROSAT US HRI Public REV0 Data
ROSID - ROSAT SIMBAD Identifications
The above catalogs are updated on a weekly basis or as new ROSAT data sets are released for public use. For descriptions of these databases, please see Legacy 3 or the online descriptions (DBHELP).
ROSLTL - ROSAT Long-term Timeline
The ROSAT Long-term Timeline has been updated to include AO4.
OPTICAL - Master Optical Catalog
In addition to the 14 online catalogs listed in Legacy 3, the OPTICAL database also includes entries from the ROSID database of ROSAT Simbad identifications.
XRAY - Master X-Ray Catalog Database
The XRAY database contains selected parameters from all HEASARC X-ray catalogs with source positions located to better than a few arc minutes. The XRAY database was created by copying all of the entries and common parameters from the following databases:
The XRAY database has many entries but relatively few parameters; it provides users with general information about X-ray sources, obtained from a variety of catalogs. XRAY is especially suitable for cone searches and cross-correlations with other databases. Each entry in XRAY has a parameter called 'database' which indicates from which original database the entry was copied; users can browse that original database should they wish to examine ALL of the parameter fields for a particular entry.
For some entries in XRAY, certain of the parameter fields are blank (or have zero values); this indicates that the original database did not contain that particular parameter. (The 'flux mCrab' parameter is often blank for this reason, for instance.)
The HEASARC continues to add and to update catalogs and data sets for the Online Service. An online listing of the latest available databases may be obtained by typing `browse' at the `HEASARC>' prompt and entering `<cr>' at each prompt for `Database name:' and `OBSERVATORY name'.
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