- ID:
- ivo://nasa.heasarc/batsegrbsp
- Title:
- CGRO/BATSE Complete Spectral Catalog of Bright GRBs
- Short Name:
- BATSE/Spec
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The CGRO/BATSE Complete Spectral Catalog of Bright Gamma-Ray Bursts (GRBs) contains the results of a systematic spectral analysis of 350 bright GRBs observed with the Burst and Transient Source Experiment (BATSE; spectral range ~ 30 keV - 2 MeV) with high temporal and spectral resolution. The sample was selected from the complete set of 2704 BATSE GRBs based on their energy fluence or peak photon flux values in order to assure good statistics, and included 17 short GRBs. To obtain well-constrained spectral parameters, several photon models were used to fit each spectrum. Spectral parameters resulting from the fits using different models were compared, and the spectral parameters that best represent each spectrum were statistically determined, taking into account the parametrization differences among the models. A thorough analysis was performed on 350 time-integrated and 8459 time-resolved burst spectra, and the effects of integration times in determining the spectral parameters were explored. Using the results, correlations among spectral parameters and their evolution pattern within each burst were studied. The resulting spectral catalog provides reliable constraints on particle acceleration and emission mechanisms in GRBs, and is the most comprehensive study of spectral properties of GRB prompt emission to date. The files containing the details of the spectral model fits to the GRBs are also available as data products associated with this Browse table. This table was created in May 2006 based on the electronic versions of Tables 1 and 9 from the published paper which were supplied by the author. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/batsedaily
- Title:
- CGRO/BATSE Daily Data
- Short Name:
- BATSEDAILY
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This is the CGRO/BATSE Daily Data database table. It contains entries for each day for which BATSE data has been processed. This database table was created and updated by the HEASARC based on information supplied by the CGRO Project. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/batseeocat
- Title:
- CGRO/BATSE Earth Occultation Catalog of Low-Energy Gamma-Ray Sources
- Short Name:
- BATSEEOCAT
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the CGRO/BATSE Earth Occultation Catalog of Low-Energy Gamma-Ray Sources. The Burst and Transient Source Experiment (BATSE), aboard the Compton Gamma Ray Observatory (CGRO), provided a record of the low-energy gamma-ray sky (20 - 1000 keV band) between 1991 April and 2000 May (a 9.1 year period). Using the Earth Occultation Technique to extract flux information, a catalog of sources using data from the BATSE large area detectors has been prepared. The first part of the catalog consists of results from the monitoring of 58 sources, mostly Galactic. For these sources, the authors included tables of flux and spectral data, and outburst times for transients, in their published paper. The authors also performed a deep-sampling of 180 objects (including the aforementioned 58 objects) combining data from the entire 9.1 year BATSE dataset. (One extra object, GRO J1735-27, has been added in this HEASARC table in addition to the 179 objects discussed in the reference paper). Source types considered were primarily accreting binaries, but a small number of representative active galaxies, X-ray-emitting stars, and supernova remnants were also included. The deep sample results include definite detections of 83 objects and possible detections of 36 additional objects. The definite detections spanned three classes of sources: accreting black hole and neutron star binaries, active galaxies and supernova remnants. Flux data for the deep sample are presented in four energy bands: 20-40, 40-70, 70-160, and 160-430 keV. The limiting average flux level (9.1 years) for the sample varies from 3.5 to 20 mCrab (5 sigma) between 20 and 430 keV, depending on systematic error, which in turn is primarily dependent on the sky location. To strengthen the credibility of detection of weaker sources (5-25 mCrab), the authors generated Earth occultation images, searched for periodic behavior using FFT and epoch folding methods, and critically evaluated the energy-dependent emission in the four flux bands. For more information, visit the website <a href="https://heasarc.gsfc.nasa.gov/docs/cgro/batse/hilev/highlevel.html">https://heasarc.gsfc.nasa.gov/docs/cgro/batse/hilev/highlevel.html</a> or refer to the Harmon et al. 2004 paper. This table was first created by the HEASARC in June 2004 based on a table supplied by one of the authors. The HEASARC updated the table and added the data products in July 2006. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cbatpicagn
- Title:
- CGRO BATSE-Observed Piccinotti Sample of Active Galactic Nuclei
- Short Name:
- GRO/Piccinott
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Compton Gamma-Ray Observatory (CGRO) BATSE Earth-occultation data have been used by Malizia et al. (1999, ApJ, 519, 637) to search for emission in the 20-100 keV band from all sources in the Piccinotti sample (Piccinotti et al. 1982, ApJ, 253, 485: the HEASARC A2PIC database), which represents the only complete 20-10 keV survey to date of the extragalactic sky down to a limiting flux of 3.1 x 10<sup>-11</sup> ergs cm<sup>-2</sup> s<sup>-1</sup>. Nearly 4 years of observations have been analyzed to reach a 5-sigma confidence level of about 7.8 x 10<sup>-11</sup> ergs cm<sup>-2</sup> s<sup>-1</sup> in the band considered. Of the 36 sources in the sample, 14 have been detected above the 5-sigma confidence level, while marginal detection (3 <= sigma <= 5) can be claimed for 13 sources; for nine objects, 2 sigma upper limits are reported. A comparison of BATSE results with data at higher energies is used to estimate the robustness of the data analysis. While the detection level of each source is reliable, the flux measurement may be overestimated in some sources by as much as 35%, probably because of incomplete data cleaning. Comparison of BATSE fluxes with X-ray fluxes obtained in the 2-10 keV range and averaged over years indicates that a canonical power law of photon index 1.7 gives a good description of the broadband spectra of bright active galactic nuclei (AGNs) and that spectral breaks preferentially occur above 100 keV. This HEASARC database was created in October 1999 based primarily on Table 1 of Malizia et al. (1999), together with the positions and HEAO-1 designations taken from the original Piccinotti Catalog (Piccinotti et al. 1982, ApJ, 253, 485: the HEASARC A2PIC database). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/batsepulsr
- Title:
- CGRO/BATSE Pulsar Observations
- Short Name:
- BATSEPULSR
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- BATSE data are divided into four groups: trigger, daily, occultation, and pulsar. Each group has structured directories beneath it containing data ordered by an appropriate criterion. Typically, several files of data are necessary to form a complete set of data for a particular entity. The BATSE pulsar data are organized similarly to the OCCULTATION data set, with the difference being in the filename extensions: 'olc' files contain on-board folded light curves, whereas 'pll' files (available in the HEASARC anonymous FTP area, but not via this database table) contain pulsar low level data. This database table allows the user to select 'olc' files or GIFs created from these files for 8 out of the several dozen pulsars for which BATSE data are available. This database table was created by the HEASARC based on information supplied by the CGRO Project. The last update was in March 2003. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/batsetrigs
- Title:
- CGRO/BATSE Trigger Data
- Short Name:
- BATSETRIGS
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The BATSE Trigger data (each trigger is specified by a unique trigger number) are a set of triggered events that are classified as either a (solar) flare, (gamma-ray) burst, soft gamma-ray repeater (sgr), terrestrial gamma flash (tgf), or tagged with the name of a known source. Not all triggers pass the acceptance tests, so not all trigger numbers are present. For each trigger, there is an associated set of FITS data files that represent the raw data sources and some higher level data products. Spectral (SD) data are prefixed with an 's' (e.g. 'sher'). Not all data types are available for all triggers due to instrument mode differences. Available data taken prior to the trigger may contain the beginning of the triggering event before it satisfied the triggering criteria. Background-type files can be used to remove background signal levels from the triggered period. The BFITS data files - containing burst and background spectral data as a function of time - and the detector response matrices (DRM) - modeling the instrument response to account for scattering and other effects - are extremely useful for gamma-ray burst analysis. Also, the BFITS and DRM files can be converted to PHA-II and RMF format for analysis with XSPEC using available FTOOLS. Please refer to the Data_Products section for more details on the various file types. A current description of the BATSE data holdings including the TRIGGER files is also available in the 1998 Legacy article, online at: <pre> <a href="https://heasarc.gsfc.nasa.gov/docs/journal/cgro7.html">https://heasarc.gsfc.nasa.gov/docs/journal/cgro7.html</a> </pre> General information about BATSE is available at the Compton Observatory Science Support Center (COSSC) web site at: <pre> <a href="https://heasarc.gsfc.nasa.gov/docs/cgro/batse/">https://heasarc.gsfc.nasa.gov/docs/cgro/batse/</a> </pre> This database table was created through a cooperative effort of the HEASARC and the Compton Observatory Science Support Center (COSSC). The table data were last updated in November, 2003. The HEASARC added Galactic coordinates in August, 2005. The "_trigger" field was renamed to "trigger_id" in September, 2020. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/comptel
- Title:
- CGRO/COMPTEL Low-Level Data and Maps
- Short Name:
- COMPTEL
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- COMPTEL is both the name of the Imaging Compton Telescope on the Compton Gamma Ray Observatory (CGRO) and the name of this HEASARC database table which allows the user to select low-level data and maps produced by this instrument. Much more information on the COMPTEL instrument, data products, and data analysis techniques can be obtained from the Compton Observatory Science Support Center (COSSC) web site at <pre> <a href="https://heasarc.gsfc.nasa.gov/docs/cgro/">https://heasarc.gsfc.nasa.gov/docs/cgro/</a> </pre> and from the article in Legacy No. 7 on the HEASARC CGRO Data Archive <pre> <a href="https://heasarc.gsfc.nasa.gov/docs/journal/cgro7.html">https://heasarc.gsfc.nasa.gov/docs/journal/cgro7.html</a> </pre> Interactions in COMPTEL occur in a two stage process: First, a Compton collision occurs in one of seven (low-Z) liquid scintillators and is usually then completely absorbed in one of fourteen (high-Z) NaI(Tl) scintillators. The unusual aspect of this detector is that the location of the gamma-ray on the sky is given by an annulus and not a point. The correlation of many events enables the localization of point sources or the creation of sky maps. Time-of-flight measurements, pulse shape discrimination and anti-coincidence shields are used to reject background events. COMPTEL has a wide field of view (about 1 steradian, equivalent to a FWHM of about 40 degrees), an angular resolution under optimal conditions of about 1 degree, and an energy resolution that ranges from 5-10% at 1 MeV. During Phase 1 of the CGRO mission, COMPTEL completed the first all-sky survey in the energy range of 0.75-30 MeV (in four energy bands). In addition, COMPTEL can measure energy spectra of solar flares or bright cosmic gamma-ray bursts between 0.1-10 MeV, and neutrons from solar flares. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/egretdata
- Title:
- CGRO/EGRET Photon Lists and Maps
- Short Name:
- GRO/EGRET
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Energetic Gamma-Ray Experiment Telescope (EGRET), which operated from 1991-April until 2000-May, was sensitive to photons in the energy range from about 30 MeV to over 20 GeV, the highest energies accessible by the CGRO instruments, and, like COMPTEL, was an imaging instrument. This catalog includes photon lists in qvp files, with one file for each EGRET viewing period. Photons which pass an energy-dependent cut on zenith angle (to exclude earth-albedo gamma rays) are processed into maps of photon counts for a standard set of energy ranges. Exposure and intensity (counts divided by exposure) maps are generated for each counts map. The counts maps typically include photons detected up to 40 degrees from the instrument axis. Most analysis has been done using data within 30 degrees of the instrument axis, where the point-spread function is narrower and the effective area greater than further off axis. All EGRET data files in the archive are the final versions, produced after the end of the mission. More detailed information about EGRET, EGRET data, and EGRET data analysis software can be found at: <pre> <a href="https://heasarc.gsfc.nasa.gov/docs/cgro/egret/egret_doc.html">https://heasarc.gsfc.nasa.gov/docs/cgro/egret/egret_doc.html</a> </pre> The data contained in this database table was supplied by the CGRO Science Support Center. The contents this table was last updated in May 2001. Galactic coordinates were added to the table by the HEASARC in August 2005. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/egrcat
- Title:
- CGRO/EGRET Revised Catalog of Gamma-Ray Sources
- Short Name:
- EGRCAT
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The CGRO/EGRET Revised Catalog of Gamma-Ray Sources (EGR) is a catalog of point gamma-ray sources detected by the EGRET detector on the Compton Gamma Ray Observatory. The authors used the entire EGRET gamma-ray dataset of reprocessed photons at energies above 100 MeV and new Galactic interstellar emission models based on CO, H I, dark gas, and interstellar radiation field data. Two different assumptions are used to describe the cosmic-ray distribution in the Galaxy to analyse the systematic uncertainties in source detection and characterization. The authors applied a 2-dimensional maximum-likelihood detection method similar to that used to analyze the 3rd EGRET catalogue (3EG: Hartman et al. 1999, ApJS, 123, 79, available as the EGRET3 Catalog in Browse). The revised EGRET catalog (EGR) lists 188 sources, 14 of which are marked as confused, in contrast to the 271 entries of the 3rd EGRET (3EG) catalog. The authors do not detect 107 sources discovered previously because additional structure is present in the interstellar background. The vast majority of them were unidentified and marked as possibly extended or confused in the 3EG catalog. In particular, the authors do not confirm most of the 3EG sources associated with the local clouds of the Gould Belt. Alternatively, they have found 30 new sources that have no 3EG counterpart. The new error circles for the confirmed 3EG sources largely overlap the previous ones, but several counterparts of particular interest discussed before, such as Sgr A*, radio galaxies, and several microquasars are now found outside the error circles. The authors cross-correlated the source positions with a large number of radio pulsars, pulsar wind nebulae, supernova remnants, OB associations, blazars and flat radiosources and they found a surprising large number of sources (87) at all latitudes that have no counterpart among the potential gamma-ray emitters. Sources found within a radius of 1.5 PSF FWHM of a very bright source, and/or with very asymmetric TS map contours, are not included in the primary list of EGR sources but are included as EGRc sources herein. The EGRc sources represent significant excesses of photons above the background that may be due to extended sources, or structures not properly modeled in the interstellar emission, or artefacts due to incorrect PSF tails. As noted above, there are 188 sources in this catalog: since there are multiple measurements for these sources corresponding to the various viewing periods, there are 1640 entries in the HEASARC's version of the Revised EGRET Catalog, corresponding to 1512 'observations' of the 174 primary gamma-ray sources plus 128 'observations' of the 14 confused sources. Thus, there are an average of about 9 entries for every gamma-ray source. This table was created by the HEASARC in March 2009 based on the electronic versions of Tables A1 and B1 from the paper, which were obtained from the CDS, their catalog J/A+A/489/849 files egr.dat and egrc.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/egret3
- Title:
- CGRO/EGRET Third Source Catalog
- Short Name:
- EGRET
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Third EGRET Catalog of High-Energy Gamma-Ray Sources is based on data obtained by the Energetic Gamma-Ray Experiment Telescope (EGRET) on board the Compton Gamma-Ray Observatory (CGRO) during the period from 1991 April 22 to 1995 October 3, corresponding to GRO Cycles 1, 2, 3, and 4. EGRET is sensitive to photons in the energy range from about 30 MeV to over 20 GeV, the highest energies accessible by the CGRO instruments, and, like COMPTEL, is an imaging instrument. In addition to including more data than the Second EGRET Catalog (2EG, Thompson et al. 1995, ApJS, 101, 259) and its supplement (2EGS, Thompson et al. 1996, ApJS, 107, 227), this catalog uses completely reprocessed data so as to correct a number of mostly minimal errors and problems. The 271 sources (E > 100 MeV) in the catalog include the single 1991 solar flare that was bright enough to detected as a source, the LMC, 5 pulsars, one probable radio galaxy detection (Cen A), and 66 high-confidence identifications of blazars (BL Lac objects, flat-spectrum radio quasars, or unidentified flat-spectrum radio sources). In addition, 27 lower-confidence potential blazar identifications are noted. Finally, the catalog contains 170 sources that are not yet firmly identified with known objects, although potential identifications have been suggested for a number of these. As already noted, there are 271 distinct sources in this catalog: since there are multiple measurements for these sources corresponding to the various viewing periods, there are 5246 entries in the HEASARC's version of the 3rd EGRET Catalog corresponding to the same number of lines in Table 4 of the published version. Thus, there are an average of about 20 entries for every distinct source. Notice that 14 sources reported in the 2nd EGRET Catalog or its supplement do not appear in this 3rd EGRET Catalog: 2EG J0403+3357, 2EG J0426+6618, 2EGS J0500+5902, 2EGS J0552-1026, 2EG J1136-0414, 2EGS J1236-0416, 2EG J1239+0441, 2EG J1314+5151, 2EG J1430+5356, 2EG J1443-6040, 2EG J1631-2845, 2EG J1709-0350, 2EG J1815+2950, and 2EG J2027+1054 due to the fact that the re-analysis of the EGRET data has dropped their statistical significance from just above the catalog threshold to just below it; additional information on these sources is provided in Table 5 of the published version of the 3rd EGRET Catalog. This database table was created by the HEASARC in June 1999, based on a machine-readable version of Table 4 of the 3rd EGRET Source Catalog that was provided by the CGRO Science Support Center (CGROSSC). Slight modifications to the Browse Object Classifications were later made in April 2001. This is a service provided by NASA HEASARC .
