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15751. The Swift/BAT hard X-ray transient monitor
ID:
ivo://CDS.VizieR/J/ApJS/209/14
Title:
The Swift/BAT hard X-ray transient monitor
Short Name:
J/ApJS/209/14
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Swift/Burst Alert Telescope (BAT) hard X-ray transient monitor provides near real-time coverage of the X-ray sky in the energy range 15-50 keV. The BAT observes 88% of the sky each day with a detection sensitivity of 5.3 mCrab for a full-day observation and a time resolution as fine as 64s. The three main purposes of the monitor are (1) the discovery of new transient X-ray sources, (2) the detection of outbursts or other changes in the flux of known X-ray sources, and (3) the generation of light curves of more than 900 sources spanning over eight years. The primary interface for the BAT transient monitor is a public Web site. Between 2005 February 12 and 2013 April 30, 245 sources have been detected in the monitor, 146 of them persistent and 99 detected only in outburst. Among these sources, 17 were previously unknown and were discovered in the transient monitor. In this paper, we discuss the methodology and the data processing and filtering for the BAT transient monitor and review its sensitivity and exposure. We provide a summary of the source detections and classify them according to the variability of their light curves. Finally, we review all new BAT monitor discoveries. For the new sources that are previously unpublished, we present basic data analysis and interpretations.
15752. The Taurus-Auriga ecosystem. I.
ID:
ivo://CDS.VizieR/J/ApJ/838/150
Title:
The Taurus-Auriga ecosystem. I.
Short Name:
J/ApJ/838/150
Date:
21 Oct 2021
Publisher:
CDS
Description:
The census of Taurus-Auriga has been assembled over seven decades and inherited the biases and incompleteness of the input studies. The unusual shape of its inferred initial mass function (IMF) and the existence of isolated disk-bearing stars suggest that additional (likely disk-free) members remain to be discovered. We therefore have begun a global reassessment of the census of Taurus-Auriga that exploits new data and better definitions of youth and kinematic membership. As a first step, we reconsider the membership of all disk-free candidate members from the literature with spectral type >=F0, 3h50min<{alpha}5h40min, and 14{deg}<{delta}<34{deg}. We combine data from the literature with Keck/HIRES and UH88/SNIFS spectra to test the membership of these candidates using the positions in the Hertzsprung-Russel diagram, proper motions, radial velocities, H{alpha}, lithium, and surface gravity. We find 218 confirmed or likely Taurus members, 160 confirmed or likely interlopers, and only 18 that lack sufficient evidence to draw firm conclusions. A significant fraction of these stars (81/218=37%) are not included in the most recent canonical member lists. There are few additional members to the immediate vicinity of the molecular clouds, preserving the IMFs that have been deemed anomalous in past work. Many of the likely Taurus members are instead distributed broadly across the search area. When combined with the known disk hosts, our updated census reveals two regimes: a high-density population with a high disk fraction (indicative of youth) that broadly traces the molecular clouds, and a low-density population with low disk fraction (hence likely older) that most likely represents previous generations of star formation.
15753. The TESS Habitable Zone Star Catalog
ID:
ivo://CDS.VizieR/J/ApJ/874/L8
Title:
The TESS Habitable Zone Star Catalog
Short Name:
J/ApJ/874/L8
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Transiting Exoplanet Survey Satellite (TESS) Habitable Zone Stars Catalog, a list of 1822 nearby stars with a TESS magnitude brighter than T=12 and reliable distances from Gaia DR2, around which the NASA's TESS mission can detect transiting planets, which receive Earth-like irradiation. For all those stars TESS is sensitive down to 2 Earth radii transiting planets during one transit. For 408 stars TESS can detect such planets down to 1 Earth-size during one transit. For 1690 stars, TESS has the sensitivity to detect planets down to 1.6 times Earth-size, a commonly used limit for rocky planets in the literature, receiving Earth-analog irradiation. We select stars from the TESS Candidate Target List, based on TESS Input Catalog Version 7. We update their distances using Gaia Data Release 2, and determine whether the stars will be observed for long enough during the 2yr prime mission to probe their Earth-equivalent orbital distance for transiting planets. We discuss the subset of 227 stars for which TESS can probe the full extent of the Habitable Zone, the full region around a star out to about a Mars-equivalent orbit. Observing the TESS Habitable Zone Catalog Stars will also give us deeper insight into the occurrence rate of planets, out to Earth-analog irradiation as well as in the Habitable Zone, especially around cool stars. We present the stars by decreasing angular separation of the 1 au equivalent distance to provide insights into which stars to prioritize for ground-based follow-up observations with upcoming extremely large telescopes.
15754. The TESS Input Catalog and Candidate Target List
ID:
ivo://CDS.VizieR/J/AJ/156/102
Title:
The TESS Input Catalog and Candidate Target List
Short Name:
J/AJ/156/102
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Transiting Exoplanet Survey Satellite (TESS) will be conducting a nearly all-sky photometric survey over two years, with a core mission goal to discover small transiting exoplanets orbiting nearby bright stars. It will obtain 30 minute cadence observations of all objects in the TESS fields of view, along with two-minute cadence observations of 200000-400000 selected stars. The choice of which stars to observe at the two-minute cadence is driven by the need to detect small transiting planets, which leads to the selection of primarily bright, cool dwarfs. We describe the catalogs assembled and the algorithms used to populate the TESS Input Catalog (TIC), including plans to update the TIC with the incorporation of the Gaia second data release (Cat. I/345) in the near future. We also describe a ranking system for prioritizing stars according to the smallest transiting planet detectable, and assemble a Candidate Target List (CTL) using that ranking. We discuss additional factors that affect the ability to photometrically detect and dynamically confirm small planets, and we note additional stellar populations of interest that may be added to the final target list. The TIC is available on the STScI MAST server, and an enhanced CTL is available through the Filtergraph data visualization portal system at the URL http://filtergraph.vanderbilt.edu/tess_ctl.
15755. The 4th IBIS/ISGRI soft gamma-ray survey catalog
ID:
ivo://CDS.VizieR/J/ApJS/186/1
Title:
The 4th IBIS/ISGRI soft gamma-ray survey catalog
Short Name:
J/ApJS/186/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, we report on the fourth soft gamma-ray source catalog obtained with the IBIS gamma-ray imager on board the INTEGRAL satellite. The scientific data set is based on more than 70Ms of high-quality observations performed during the first five and a half years of the Core Program and public observations. Compared to previous IBIS surveys, this catalog includes a substantially increased coverage of extragalactic fields, and comprises more than 700 high-energy sources detected in the energy range 17-100keV, including both transients and faint persistent objects that can only be revealed with longer exposure times. A comparison is provided with the latest Swift/BAT survey results.
15756. The Third Bologna Survey (B3)
ID:
ivo://CDS.VizieR/VIII/37
Title:
The Third Bologna Survey (B3)
Short Name:
VIII/37
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue contains the first section of a sky survey performed at 408MHz with the 'Northern Cross' Radiotelescope. It contains about 13.000 radiosources. Although sources down to about 70mJy were measured, only sources brighter than 0.10Jy are retained in the catalogue. According to our estimate of confusion errors, this corresponds to a detection threshold of about 5{sigma}. The list is meant to include all the sources with a measured flux S>0.10Jy, in the sky area included between the declinations +37{deg}15' and +47{deg}37', epoch 1978.0. A number of zones however are affected by interferences, malfunctions, etc. The principal one is centered about the radiosource Cyg A, which is itself in the map, but not in the catalogue. The zone between RA 19h30m to 20h30m is entirely lacking, due to strong confusion. In the zone from 19h00m to 19h30m and from 20h30m to 21h00m, only sources brighter than 0.75Jy are listed, and to this level the catalogue is espected to be complete. For detailed discussion of the completeness of the catalogue see the original publication cited above.
15757. The third Fermi/GBM GRB catalog (6yr)
ID:
ivo://CDS.VizieR/J/ApJS/223/28
Title:
The third Fermi/GBM GRB catalog (6yr)
Short Name:
J/ApJS/223/28
Date:
21 Oct 2021
Publisher:
CDS
Description:
Since its launch in 2008, the Fermi Gamma-ray Burst Monitor (GBM) has triggered and located on average approximately two {gamma}-ray bursts (GRBs) every three days. Here, we present the third of a series of catalogs of GRBs detected by GBM, extending the second catalog by two more years through the middle of 2014 July. The resulting list includes 1405 triggers identified as GRBs. The intention of the GBM GRB catalog is to provide information to the community on the most important observables of the GBM-detected GRBs. For each GRB, the location and main characteristics of the prompt emission, the duration, peak flux, and fluence are derived. The latter two quantities are calculated for the 50-300keV energy band where the maximum energy release of GRBs in the instrument reference system is observed, and also for a broader energy band from 10 to 1000keV, exploiting the full energy range of GBM's low-energy [NaI[Tl)] detectors. Using statistical methods to assess clustering, we find that the hardness and duration of GRBs are better fit by a two-component model with short-hard and long-soft bursts than by a model with three components. Furthermore, information is provided on the settings and modifications of the triggering criteria and exceptional operational conditions during years five and six in the mission. This third catalog is an official product of the Fermi GBM science team, and the data files containing the complete results are available from the High-Energy Astrophysics Science Archive Research Center.
15758. The third Fermi-LAT >10GeV catalog (3FHL)
ID:
ivo://CDS.VizieR/J/ApJS/232/18
Title:
The third Fermi-LAT >10GeV catalog (3FHL)
Short Name:
J/ApJS/232/18
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of sources detected above 10GeV by the Fermi Large Area Telescope (LAT) in the first 7 years of data using the Pass 8 event-level analysis. This is the Third Catalog of Hard Fermi-LAT Sources (3FHL), containing 1556 objects characterized in the 10GeV-2TeV energy range. The sensitivity and angular resolution are improved by factors of 3 and 2 relative to the previous LAT catalog at the same energies (1FHL). The vast majority of detected sources (79%) are associated with extragalactic counterparts at other wavelengths, including 16 sources located at very high redshift (z>2). Of the sources, 8% have Galactic counterparts and 13% are unassociated (or associated with a source of unknown nature). The high-latitude sky and the Galactic plane are observed with a flux sensitivity of 4.4 to 9.5x10^-11^ph/cm^2^/s, respectively (this is approximately 0.5% and 1% of the Crab Nebula flux above 10GeV). The catalog includes 214 new {gamma}-ray sources. The substantial increase in the number of photons (more than 4 times relative to 1FHL and 10 times to 2FHL) also allows us to measure significant spectral curvature for 32 sources and find flux variability for 163 of them. Furthermore, we estimate that for the same flux limit of 10^-12^erg/cm^2^/s, the energy range above 10GeV has twice as many sources as the range above 50GeV, highlighting the importance, for future Cherenkov telescopes, of lowering the energy threshold as much as possible.
15759. The third realization of the ICRF, ICRF3
ID:
ivo://CDS.VizieR/J/A+A/644/A159
Title:
The third realization of the ICRF, ICRF3
Short Name:
J/A+A/644/A159
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new realization of the International Celestial Reference Frame (ICRF) is presented based on the work achieved by a working group of the International Astronomical Union (IAU) mandated for this purpose. This new realization follows the initial realization of theICRF completed in 1997 and its successor, ICRF2, adopted as a replacement in 2009. The new frame, referred to as ICRF3, is based on nearly 40 years of data acquired by very long baseline interferometry at the standard geodetic and astrometric radio frequencies (8.4 and 2.3GHz), supplemented with data collected at higher radio frequencies (24GHz and dual-frequency 32 and 8.4GHz) over the past 15 years. State-of-the-art astronomical and geophysical modeling has been used to analyze these data and derive source positions. The modeling integrates, for the first time, the effect of the galactocentric acceleration of the solar system (directly estimated from the data) which, if not considered, induces significant deformation of the frame due to the data span. The new frame includes positions at 8.4GHz for 4536 extragalactic sources. Of these, 303 sources, uniformly distributed on the sky, are identified as "defining sources" and as such serve to define the axes of the frame. Positions at 8.4GHz are supplemented with positions at 24GHz for 824 sources and at 32GHz for 678 sources. In all, ICRF3 comprises 4588 sources, with three-frequency positions available for 600 of these. Source positions have been determined independently at each of the frequencies in order to preserve the underlying astrophysical content behind such positions. They are reported for epoch 2015.0 and must be propagated for observations at other epochs for the most accurate needs, accounting for the acceleration toward the Galactic center, which results in a dipolar proper motion field of amplitude 0.0058 milliarcsecond/yr (mas/yr). The frame is aligned onto the International Celestial Reference System to within the accuracy of ICRF2 and shows a median positional uncertainty of about 0.1mas in right ascension and 0.2 mas in declination, with a noise floor of 0.03mas in the individual source coordinates. A subset of 500 sources is found to have extremely accurate positions, in the range of 0.03 to 0.06mas, at the traditional 8.4GHz frequency. Comparing ICRF3 with the recently released Gaia Celestial Reference Frame 2 in the optical domain, there is no evidence for deformations larger than 0.03 mas between the two frames, in agreement with the ICRF3 noise level. Significant positional offsets between the three ICRF3 frequencies are detected for about 5% of the sources.Moreover, a notable fraction (22%) of the sources shows optical and radio positions that are significantly offset. There are indications that these positional offsets may be the manifestation of extended source structures. This third realization of the ICRF was adopted by the IAU at its 30th General Assembly in August 2018 and replaced the previous realization, ICRF2, on January 1, 2019.
15760. The third Swift/BAT GRB catalog (past ~11yrs) (BAT3)
ID:
ivo://CDS.VizieR/J/ApJ/829/7
Title:
The third Swift/BAT GRB catalog (past ~11yrs) (BAT3)
Short Name:
J/ApJ/829/7
Date:
21 Oct 2021
Publisher:
CDS
Description:
To date, the Burst Alert Telescope (BAT) onboard Swift has detected ~1000 gamma-ray bursts (GRBs), of which ~360 GRBs have redshift measurements, ranging from z=0.03 to z=9.38. We present the analyses of the BAT-detected GRBs for the past ~11 years up through GRB151027B. We report summaries of both the temporal and spectral analyses of the GRB characteristics using event data (i.e., data for each photon within approximately 250s before and 950s after the BAT trigger time), and discuss the instrumental sensitivity and selection effects of GRB detections. We also explore the GRB properties with redshift when possible. The result summaries and data products are available at http://swift.gsfc.nasa.gov/results/batgrbcat/index.html. In addition, we perform searches for GRB emissions before or after the event data using the BAT survey data. We estimate the false detection rate to be only one false detection in this sample. There are 15 ultra-long GRBs (~2% of the BAT GRBs) in this search with confirmed emission beyond ~1000s of event data, and only two GRBs (GRB 100316D and GRB 101024A) with detections in the survey data prior to the starting of event data.

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