- ID:
- ivo://nasa.heasarc/batse4b
- Title:
- CGRO/BATSE 4B Catalog
- Short Name:
- BATSE4B
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table comprises the 4th BATSE Gamma-Ray Burst Catalog, hereafter referred to as 4B. It specifies the locations and times for 1637 triggered gamma-ray bursts observed from 19 April, 1991 until 29 August, 1996. It therefore includes the data from the 3B catalog. The only revisions from the 3B catalog are improved locations for the trigger #s 741, 2311, and 3155. Bursts since the end of the 1B catalog (March 1992) occurred when the Compton Gamma-Ray Observatory (CGRO) tape recorders were experiencing numerous errors. Consequently, there are gaps in the data of many bursts that preclude valid measurement of peak flux, peak rate, fluence, or duration. Peak rates on the 1 second timescale from each detector are almost always available. These data (called MAXBC rates) can be used to determine burst location. Previous difficulties with this data type have been largely removed, and we now believe that the systematic errors for MAXBC-located bursts are the same as for bursts located with other data types. It is still true however, that the MAXBC-located bursts usually have larger statistical errors than would be the case if another data type were available. The parameter called comments_position in this database contains comments on MAXBC-located bursts. A number of CGRO and BATSE flight software changes have significantly reduced the problem of data gaps since March of 1993. This database table was created by the HEASARC in March 1999, based on data supplied by the CGRO Science Support Center. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/bat5bgrbsp
- Title:
- CGRO/BATSE 5B Gamma-Ray Burst Spectral Catalog
- Short Name:
- BAT5BGRBSP
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The CGRO/BATSE 5B Gamma-Ray Burst Spectral Catalog contains the results of systematic spectral analyses of gamma-ray bursts (GRBs) detected with the Burst and Transient Source Experiment (BATSE) on board the Compton Gamma-Ray Observatory (CGRO) during its entire nine years of operation. This catalog contains two types of spectra extracted from 2,145 GRBs, and fitted with five different spectral models resulting in a compendium of over 19,000 spectra. The models were selected based on their empirical importance to the spectral shape of many GRBs, and the analysis performed was devised to be as thorough and objective as possible. In their paper, the authors describe in detail their procedures and criteria for the analyses, and present the bulk results in the form of parameter distributions. This catalog should be considered an official product from the BATSE Science Team, and the data files containing the complete results are soon to be available from the HEASARC. This table lists all of the spectroscopy results of gamma-ray bursts observed by a subset of the 8 BATSE Large Area Detectors. BATSE consisted, in part, of an array of 8 sodium iodide Large Area Detectors (LADs) which covered the energy range from ~20 keV - 2 MeV. The LAD detectors were placed at each of the eight corners of the CGRO spacecraft with an outward orientation such that the entire sky not occulted by the Eartt was observed. The spectrum files ("scat" files) available as FITS-format data products associated with this catalog provide parameter values and goodness-of-fit measures for different types of spectral fits and models. These fits are performed using 14-channel data, usually 2-second resolution CONT data. There are currently two spectrum categories: <pre> * Peak flux ('pflx') - a single spectrum over a 2.05-second time range at the peak flux of the burst * Fluence ('flnc') - a single spectrum over the entire burst duration </pre> The quoted fluxes and fluences are for the 20 keV - 2 MeV energy range, notice. The scat files have two extensions. The first extension gives detector-specific information, including photon fluxes and fluences for each detector, which are provided for each energy channel. The second extension provides derived quantities such as flux, fluence and model parameters for the joint fit of all included detectors. The scat files and their energy-resolved quantities contained in these two extensions will be available soon in the HEASARC data archive. Quantities derived from these spectral fits are available in the present table, as described below and in the Goldstein et al. (2013) reference paper. The spectra are fit with a number of models, with the signal-to-noise ratio of the spectrum often determining whether a more complex model is statistically favored. The current set is: <pre> * Power law ('plaw'), * Comptonized (exponentially attenuated power law; 'comp') * Band ('band') * Smoothly broken power law ('sbpl') * Log_10 Gaussian ('glog') </pre> The full details of these models are presented in Section 4 of the reference paper. The type of spectrum and spectral model are coded into the parameter names (and the associated file names) using the acronyms given above. Thus for example, the parameters with names beginning with 'flnc_glog' contain the results from fits to the fluence spectra using Log<sub>10</sub> Gaussian models. The corresponding spectrum file for the burst with trigger number 105 with the results from a fit to the fluence spectrum using a Log<sub>10</sub> Gaussian model is named scat_0105_flnc_glog_v00.fit. Please note that this table lists the raw results of each spectral fit to each GRB. In cases where the spectral fit failed, the values reported are those that initialized the spectral fit. If the uncertainty on the spectral parameters is reported as zero (no uncertainty), then the fit failed. In a few cases throughout this table, the uncertainties for certain spectral parameters may be reported as '9999.99' which indicates that the uncertainty on that parameter is completely unconstrained. An example of this is when the spectral data from a burst is fitted with a BAND function but is unable to constrain the high-energy index. In this case, the best fit centroid value of the high-energy index parameter is reported, and the '9999.99' value is reported for the uncertainty. This table was created by the HEASARC in November 2013 based on electronic versions of Tables 6 through 10, inclusive, from the reference paper which were obtained from the ApJS web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/batsedaily
- Title:
- CGRO/BATSE Daily Data
- Short Name:
- BATSEDAILY
- Date:
- 10 May 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:
- 10 May 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/batsegrb
- Title:
- CGRO/BATSE Gamma-Ray Burst Catalog
- Short Name:
- BATSEGRB
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table comprises the gamma-ray bursts detected by the BATSE instrument on the Compton Gamma-Ray Observatory (CGRO). It includes the gamma-ray bursts from the BATSE 4B Catalog (triggers 105 through 5586, observed between April 19, 1991, and August 29, 1996) as well as a large number of triggered bursts since the publication of the BATSE 4B Catalog. All BATSE trigger data from the CGRO mission are available through this facility. As part of a final archiving effort, the BATSE instrument team is making minor refinements to certain data products. These revised products will be delivered to the HEASARC as soon as they are produced and tested. Certain burst catalog parameters, notably the position information, may be revised through improved analyses and instrumental calibration. The final catalog will be posted here as soon as it is completed. The data files used to construct this database table are obtained from the following pages on the BATSE GRB Team website: <pre> BATSE Current Gamma-Ray Burst Catalog: <a href="http://gammaray.msfc.nasa.gov/batse/grb/catalog/current/">http://gammaray.msfc.nasa.gov/batse/grb/catalog/current/</a> Some flux and fluence data and all the comments are from the BATSE 4B Catalog: <a href="http://gammaray.msfc.nasa.gov/batse/grb/catalog/4b/">http://gammaray.msfc.nasa.gov/batse/grb/catalog/4b/</a> </pre> <p> This database table was first created at the HEASARC in June 2001. The HEASARC version is automatically updated within one week of whenever the data files located at <a href="http://gammaray.msfc.nasa.gov/batse/grb/catalog/current/">http://gammaray.msfc.nasa.gov/batse/grb/catalog/current/</a> are changed. 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:
- 10 May 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:
- 10 May 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:
- 10 May 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:
- 10 May 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:
- 10 May 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 .
