- ID:
- ivo://CDS.VizieR/J/ApJ/826/228
- Title:
- The Fermi-GBM three-year X-ray burst catalog
- Short Name:
- J/ApJ/826/228
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Fermi Gamma-ray Burst Monitor (GBM) is an all-sky gamma-ray monitor well known in the gamma-ray burst (GRB) community. Although GBM excels in detecting the hard, bright extragalactic GRBs, its sensitivity above 8 keV and its all-sky view make it an excellent instrument for the detection of rare, short-lived Galactic transients. In 2010 March, we initiated a systematic search for transients using GBM data. We conclude this phase of the search by presenting a three-year catalog of 1084 X-ray bursts. Using spectral analysis, location, and spatial distributions we classified the 1084 events into 752 thermonuclear X-ray bursts, 267 transient events from accretion flares and X-ray pulses, and 65 untriggered gamma-ray bursts. All thermonuclear bursts have peak blackbody temperatures broadly consistent with photospheric radius expansion (PRE) bursts. We find an average rate of 1.4 PRE bursts per day, integrated over all Galactic bursters within about 10 kpc. These include 33 and 10 bursts from the ultra-compact X-ray binaries 4U 0614+09 and 2S 0918-549, respectively. We discuss these recurrence times and estimate the total mass ejected by PRE bursts in our Galaxy.
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- ID:
- ivo://CDS.VizieR/J/ApJS/247/33
- Title:
- The Fermi LAT fourth source catalog (4FGL)
- Short Name:
- J/ApJS/247/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the fourth Fermi Large Area Telescope catalog (4FGL) of {gamma}-ray sources. Based on the first eight years of science data from the Fermi Gamma-ray Space Telescope mission in the energy range from 50MeV to 1TeV, it is the deepest yet in this energy range. Relative to the 3FGL catalog, the 4FGL catalog has twice as much exposure as well as a number of analysis improvements, including an updated model for the Galactic diffuse {gamma}-ray emission, and two sets of light curves (one-year and two-month intervals). The 4FGL catalog includes 5064 sources above 4{sigma} significance, for which we provide localization and spectral properties. Seventy-five sources are modeled explicitly as spatially extended, and overall, 358 sources are considered as identified based on angular extent, periodicity, or correlated variability observed at other wavelengths. For 1336 sources, we have not found plausible counterparts at other wavelengths. More than 3130 of the identified or associated sources are active galaxies of the blazar class, and 239 are pulsars.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/8
- Title:
- The first Fermi LAT SNR catalog (1SC)
- Short Name:
- J/ApJS/224/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed the first systematic survey at energies from 1 to 100GeV using data from the Fermi Large Area Telescope (LAT). Based on the spatial overlap of sources detected at GeV energies with SNRs known from radio surveys, we classify 30 sources as likely GeV SNRs. We also report 14 marginal associations and 245 flux upper limits. A mock catalog in which the positions of known remnants are scrambled in Galactic longitude allows us to determine an upper limit of 22% on the number of GeV candidates falsely identified as SNRs. We have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all Galactic Fermi LAT analyses. By studying remnants uniformly in aggregate, we measure the GeV properties common to these objects and provide a crucial context for the detailed modeling of individual SNRs. Combining our GeV results with multiwavelength (MW) data, including radio, X-ray, and TeV, we demonstrate the need for improvements to previously sufficient, simple models describing the GeV and radio emission from these objects. We model the GeV and MW emission from SNRs in aggregate to constrain their maximal contribution to observed Galactic cosmic rays.
- ID:
- ivo://CDS.VizieR/J/ApJ/698/1095
- Title:
- The FIRST-2MASS red QSO survey. II.
- Short Name:
- J/ApJ/698/1095
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results on a survey to find extremely dust-reddened Type 1 quasars. Combining the FIRST radio survey, the 2MASS Infrared Survey and the Sloan Digital Sky Survey, we have selected a candidate list of 122 potential red quasars. With more than 80% spectroscopically identified objects, well over 50% are classified as dust-reddened Type 1 quasars, whose reddenings (E(B-V)) range from approximately 0.1 to 1.5mag. They lie well off the color selection windows usually used to detect quasars and many fall within the stellar locus, which would have made it impossible to find these objects with traditional color selection techniques. The reddenings found are much more consistent with obscuration happening in the host galaxy rather than stemming from the dust torus. We find an unusually high fraction of broad absorption line (BAL) quasars at high redshift, all but one of them belonging to the low-ionization BAL (LoBAL) class and many also showing absorption in the metastable FeII line (FeLoBAL). The discovery of further examples of dust-reddened LoBAL quasars provides more support for the hypothesis that BAL quasars (at least LoBAL quasars) represent an early stage in the lifetime of the quasar. The fact that we see such a high fraction of BALs could indicate that the quasar is in a young phase in which quasar feedback from the BAL winds is suppressing star formation in the host galaxy.
- ID:
- ivo://CDS.VizieR/J/AJ/158/13
- Title:
- The first 300 stars observed by the GPIES
- Short Name:
- J/AJ/158/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a statistical analysis of the first 300 stars observed by the Gemini Planet Imager Exoplanet Survey. This subsample includes six detected planets and three brown dwarfs; from these detections and our contrast curves we infer the underlying distributions of substellar companions with respect to their mass, semimajor axis, and host stellar mass. We uncover a strong correlation between planet occurrence rate and host star mass, with stars M_*_>1.5 M_{sun}_ more likely to host planets with masses between 2 and 13 M_Jup_ and semimajor axes of 3-100 au at 99.92% confidence. We fit a double power-law model in planet mass (m) and semimajor axis (a) for planet populations around high-mass stars (M_*_>1.5 M_{sun}_) of the form d^2^N/(dm da){prop.to}m^{alpha}^{alpha}^{beta}^, finding {alpha}=-2.4+/-0.8 and {beta}=-2.0+/-0.5, and an integrated occurrence rate of 9_-4_^+5^% between 5-13 M_Jup_ and 10-100 au. A significantly lower occurrence rate is obtained for brown dwarfs around all stars, with 0.8_-0.5_^+0.8^% of stars hosting a brown dwarf companion between 13-80 M_Jup_ and 10-100 au. Brown dwarfs also appear to be distributed differently in mass and semimajor axis compared to giant planets; whereas giant planets follow a bottom-heavy mass distribution and favor smaller semimajor axes, brown dwarfs exhibit just the opposite behaviors. Comparing to studies of short-period giant planets from the radial velocity method, our results are consistent with a peak in occurrence of giant planets between ~1 and 10 au. We discuss how these trends, including the preference of giant planets for high-mass host stars, point to formation of giant planets by core/pebble accretion, and formation of brown dwarfs by gravitational instability.
- ID:
- ivo://CDS.VizieR/VIII/71
- Title:
- The FIRST Survey Catalog, Version 03Apr11
- Short Name:
- VIII/71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Faint Images of the Radio Sky at Twenty centimeters (FIRST) began in 1993. It uses the VLA (Very Large Array, a facility of the National Radio Observatory (NRAO)) at a frequency of 1.4GHz, and it is slated to 10,000 deg^2^ of the North and South Galactic Caps, to a sensitivity of about 1mJy with an angular resolution of about 5". The images produced by an automated mapping pipeline have pixels of 1.8arcsec, a typical rms of 0.15mJy, and a resolution of 5arcsec; the images are available on the Internet (see the FIRST home page at http://sundog.stsci.edu/ for details). The source catalogue is derived from the images. This version (2003 Apr 11) of the FIRST Survey is derived from the data taken from 1993 through September 2002, and contains about 811,000 sources covering 8422 square degrees in the North Galactic cap and 611 square degrees in the South Galactic cap. The FIRST survey is now substantially complete; the planned additions include a version with improved sidelobe flagging and deeper observations of the southern equatorial strip (with variability information), and maybe a small amount of additional data to fill holes within the surveyed area.
- ID:
- ivo://CDS.VizieR/VIII/92
- Title:
- The FIRST Survey Catalog, Version 2014Dec17
- Short Name:
- VIII/92
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Faint Images of the Radio Sky at Twenty centimeters (FIRST) began in 1993. It uses the VLA (Very Large Array, a facility of the National Radio Observatory (NRAO)) at a frequency of 1.4GHz, and it is slated to 10,000 deg^2^ of the North and South Galactic Caps, to a sensitivity of about 1mJy with an angular resolution of about 5''. The images produced by an automated mapping pipeline have pixels of 1.8'', a typical rms of 0.15mJy, and a resolution of 5''; the images are available on the Internet (see the FIRST home page at http://sundog.stsci.edu/ for details). The source catalogue is derived from the images. This catalog from the 1993 through 2011 observations contains 946,432 sources from the north and south Galactic caps. It covers a total of 10,575 square degrees of the sky (8444 square degrees in the north and 2131 square degrees in the south). In this version of the catalog, images taken in the the new EVLA configuration have been re-reduced using shallower CLEAN thresholds in order to reduce the "CLEAN bias" in those images. Also, the EVLA images are not co-added with older VLA images to avoid problems resulting from the different frequencies and noise properties of the configurations. That leads to small gaps in the sky coverage at boundaries between the EVLA and VLA regions. As a result, the area covered by this release of the catalog is about 60 square degrees smaller than the earlier release of the catalog (13Jun05, also available here as the "first13.dat" file), and the total number of sources is reduced by nearly 25,000. The previous version of the catalog does have sources in the overlap regions, but their flux densities are considered unreliable due to calibration errors. The flux densities should be more accurate in this catalog, biases are smaller, and the incidence of spurious sources is also reduced. Over most of the survey area, the detection limit is 1 mJy. A region along the equatorial strip (RA=21.3 to 3.3hr, Dec=-1 to 1deg) has a deeper detection threshold because two epochs of observation were combined. The typical detection threshold in this region is 0.75mJy. There are approximately 4,500 sources below the 1mJy threshold used for most previous versions of the catalog. The previous versions http://sundog.stsci.edu/first/catalogs/
- ID:
- ivo://CDS.VizieR/VIII/90
- Title:
- The FIRST Survey Catalog, Version 12Feb16
- Short Name:
- VIII/90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Faint Images of the Radio Sky at Twenty centimeters (FIRST) began in 1993. It uses the VLA (Very Large Array, a facility of the National Radio Observatory (NRAO)) at a frequency of 1.4GHz, and it is slated to 10,000 deg^2^ of the North and South Galactic Caps, to a sensitivity of about 1mJy with an angular resolution of about 5''. The images produced by an automated mapping pipeline have pixels of 1.8'', a typical rms of 0.15mJy, and a resolution of 5''; the images are available on the Internet (see the FIRST home page at http://sundog.stsci.edu/ for details). The source catalogue is derived from the images. This catalog from the 1993 through 2011 observations contains 946,464 sources from the north and south Galactic caps. It covers a total of 10,635 square degrees of the sky (8444 square degrees in the north and 2191 square degrees in the south.) The catalog format differs from the previous version: The contents of the sidelobe flag column has changed to a sidelobe probability estimate, and columns have been added with information on optical and infrared counterparts from the SDSS and 2MASS catalogs. There is no GSC2 information in this version.
- ID:
- ivo://CDS.VizieR/VIII/51
- Title:
- the FIRST Survey, version 1998Feb
- Short Name:
- VIII/51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The FIRST survey to produce Faint Images of the Radio Sky at Twenty centimeters began in 1993. It uses the VLA (Very Large Array, a facility of the National Radio Observatory (NRAO)) at a frequency of 1.4GHz, and it is slated to 10,000 deg^2^ to a sensitivity of about 1mJy with an angular resolution of about 5". The co-added images are available on the Internet (see the FIRST home page at http://sundog.stsci.edu/ for details). The source catalogue is derived from the images. This version of the FIRST Survey is derived from the 1993 through 1997 observations, and contains 382,892 sources for the north Galactic cap, and 54,537 sources for the south Galactic cap. The northern catalog covers about 4150 square degrees of sky, including most of the area: 7h20m < RA(2000) < 17h20m 22.2{deg} < Dec < 57.6{deg} The southern catalog covers about 610 square degrees of sky, including two narrow strips in the area 21h20m < RA(2000) < 3h20m -11.5{deg} < Dec < 1.6{deg}
- ID:
- ivo://CDS.VizieR/VIII/59
- Title:
- the FIRST Survey, version 1999Jul
- Short Name:
- VIII/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The FIRST survey to produce Faint Images of the Radio Sky at Twenty centimeters began in 1993. It uses the VLA (Very Large Array, a facility of the National Radio Observatory (NRAO)) at a frequency of 1.4GHz, and it is slated to 10,000 deg^2^ to a sensitivity of about 1mJy with an angular resolution of about 5". The co-added images are available on the Internet (see the FIRST home page at http://sundog.stsci.edu/ for details). The source catalogue is derived from the images. This version of the FIRST Survey is derived from the 1993 through 1998 observations, and contains 549,707 sources covering the north and south Galactic caps. The catalog covers about a total of 6060 square degrees of sky (5450 square degrees in the north and 610 square degrees in the south). No new data were taken for the south Galactic cap from the preceding version (catalog <VIII/51>), but the southern images south of about -2 degrees were reprocessed with an improved pipeline script that substantially reduces the sidelobe levels in a small fraction of the fields. Consequently, many of the southern sources have slight changes in their positions, flux densities, and other properties; a small number of sources from the previous catalog are missing from this catalog.