- ID:
- ivo://CDS.VizieR/J/ApJ/692/758
- Title:
- BAL QSOs in SDSS-DR5
- Short Name:
- J/ApJ/692/758
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 5039 broad absorption line (BAL) quasars (QSOs) in the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) QSO catalog that have absorption troughs covering a continuous velocity range >=2000km/s. We have fitted ultraviolet (UV) continua and line emission in each case, enabling us to report common diagnostics of BAL strengths and velocities in the range -25000 to 0km/s for SiIV1400, CIV1549, AlIII1857, and MgII2799. We calculate these diagnostics using the spectrum listed in the DR5 QSO catalog, and also for spectra from additional SDSS observing epochs when available. In cases where BAL QSOs have been observed with Chandra or XMM-Newton, we report the X-ray monochromatic luminosities of these sources. We confirm and extend previous findings that BAL QSOs are more strongly reddened in the rest-frame UV than non-BAL QSOs, and that BAL QSOs are relatively X-ray weak compared to non-BAL QSOs.
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- ID:
- ivo://CDS.VizieR/J/ApJ/788/81
- Title:
- BANYAN III. RVel and rotation of low-mass stars
- Short Name:
- J/ApJ/788/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on high-resolution spectra obtained with PHOENIX at Gemini South, CRIRES at VLT-UT1, and ESPaDOnS at the Canada-France-Hawaii Telescope, we present new measurements of the radial and projected rotational velocities of 219 low-mass stars. The target likely membership was initially established using the Bayesian analysis tool recently presented in Malo et al. (Paper I: 2013, J/ApJ/762/88), taking into account only the position, proper motion, and photometry of the stars to assess their membership probability. In the present study, we include radial velocity as an additional input to our analysis, and in doing so we confirm the high membership probability for 130 candidates: 27 in {beta} Pictoris, 22 in Tucana-Horologium, 25 in Columba, 7 in Carina, 18 in Argus and 18 in AB Doradus, and 13 with an ambiguous membership. Our analysis also confirms the membership of 57 stars proposed in the literature. A subsample of 16 candidates was observed at 3 or more epochs, allowing us to discover 6 new spectroscopic binaries. The fraction of binaries in our sample is 25%, consistent with values in the literature. Of the stars in our sample, 20% show projected rotational velocities (vsin i) higher than 30 km/s and therefore are considered as fast rotators. A parallax and other youth indicators are still needed to fully confirm the 130 highly probable candidates identified here as new bona fide members. Finally, based on the X-ray emission of bona fide and highly probable group members, we show that for low-mass stars in the 12-120Myr age range, the X-ray luminosity is an excellent indicator of youth and better than the more traditionally used R_X_parameter, the ratio of X-ray to bolometric luminosity.
- ID:
- ivo://CDS.VizieR/J/ApJ/881/154
- Title:
- BAT AGN spectroscopic survey. XVI. Blazars
- Short Name:
- J/ApJ/881/154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The recently released 105-month Swift-Burst Alert Telescope (BAT) all-sky hard X-ray survey catalog presents an opportunity to study astrophysical objects detected in the deepest look at the entire hard X-ray (14-195keV) sky. Here we report the results of a multifrequency study of 146 blazars from this catalog, quadrupling the number compared to past studies, by utilizing recent data from the Fermi-Large Area Telescope (LAT), Swift-BAT, and archival measurements. In our {gamma}-ray analysis of ~10yr of the LAT data, 101 are found as {gamma}-ray emitters, whereas, 45 remains LAT undetected. We model the broadband spectral energy distributions with a synchrotron-inverse Compton radiative model. On average, BAT detected sources host massive black holes (M_bh_~10^9^M_{sun}_) and luminous accretion disks (L_d_~10^46^erg/s). At high redshifts (z>2), BAT blazars host more powerful jets with luminous accretion disks compared to those detected only with Fermi-LAT. We find good agreement in the black hole masses derived from the single-epoch optical spectroscopic measurements and standard accretion disk modeling approaches. Other physical properties of BAT blazars are similar to those known for Fermi-LAT detected objects.
- ID:
- ivo://CDS.VizieR/J/ApJ/896/122
- Title:
- BAT AGN Spectroscopic Survey. XVIII. Periodic var.
- Short Name:
- J/ApJ/896/122
- Date:
- 03 Dec 2021 13:15:09
- Publisher:
- CDS
- Description:
- Theory predicts that a supermassive black hole binary (SMBHB) could be observed as a luminous active galactic nucleus (AGN) that periodically varies on the order of its orbital timescale. In X-rays, periodic variations could be caused by mechanisms including relativistic Doppler boosting and shocks. Here we present the first systematic search for periodic AGNs using 941 hard X-ray light curves (14-195keV) from the first 105 months of the Swift Burst Alert Telescope (BAT) survey (2004-2013). We do not find evidence for periodic AGNs in Swift-BAT, including the previously reported SMBHB candidate MCG+11-11-032. We find that the null detection is consistent with the combination of the upper-limit binary population in AGNs in our adopted model, their expected periodic variability amplitudes, and the BAT survey characteristics. We have also investigated the detectability of SMBHBs against normal AGN X-ray variability in the context of the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) survey. Under our assumptions of a binary population and the periodic signals they produce, which have long periods of hundreds of days, up to 13% true periodic binaries can be robustly distinguished from normal variable AGNs with the ideal uniform sampling. However, we demonstrate that realistic eROSITA sampling is likely to be insensitive to long-period binaries because longer observing gaps reduce their detectability. In contrast, large observing gaps do not diminish the prospect of detecting binaries of short, few-day periods, as 19% can be successfully recovered, the vast majority of which can be identified by the first half of the survey.
- ID:
- ivo://CDS.VizieR/J/ApJ/678/102
- Title:
- BAT X-ray survey. I.
- Short Name:
- J/ApJ/678/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We applied the maximum likelihood (ML) method, as an image reconstruction algorithm, to the BAT (Burst Alert Telescope) X-Ray Survey (BXS). This method was specifically designed to preserve the full statistical information in the data and to avoid mosaicking of many exposures with different pointing directions, thus reducing systematic errors when co-adding images. We reconstructed, in the 14-170keV energy band, the image of a 90x90deg^2^ sky region, centered on (RA, DE)=(105{deg}, -25{deg}), which BAT surveyed with an exposure time of ~1Ms (in 2005 November). The best sensitivity in our image is ~0.85mCrab or 2.0x10^-11^ergs/cm^2^. We detect 49 hard X-ray sources above the 4.5{sigma} level; of these, only 12 were previously known as hard X-ray sources (>15keV). Swift XRT observations allowed us to firmly identify the counterparts for 15 objects, while 2 objects have Einstein IPC counterparts (Harris et al., 1990, in Imaging X-Ray Astronomy. A Decade of Achievements, ed. M. Elvis (Cambridge: Cambridge Univ. Press), 309); in addition to those, we found a likely counterpart for 13 objects by correlating our sample with the ROSAT All-Sky Survey Bright Source Catalog (Voges et al., 1999, Cat. <IX/10>). Seven objects remain unidentified.
- ID:
- ivo://CDS.VizieR/J/ApJ/673/96
- Title:
- BAT X-ray Survey - III
- Short Name:
- J/ApJ/673/96
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this concluding part of the series of three papers dedicated to the Swift BAT hard X-ray survey (BXS), we focus on the X-ray spectral analysis and statistical properties of the source sample. Using a dedicated method to extract time-averaged spectra of BAT sources, we show that Galactic sources have, generally, softer spectra than extragalactic objects and that Seyfert 2 galaxies are harder than Seyfert 1's.
- ID:
- ivo://CDS.VizieR/J/ApJ/704/1586
- Title:
- BCGs with radio AGN
- Short Name:
- J/ApJ/704/1586
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The radio active galactic nucleus (AGN) feedback in X-ray cool cores has been proposed as a crucial ingredient in the evolution of baryonic structures. However, it has long been known that strong radio AGNs also exist in "noncool core" clusters, which brings up the question whether an X-ray cool core is always required for the radio feedback. In this work, we present a systematic analysis of brightest cluster galaxies (BCGs) and strong radio AGNs in 152 groups and clusters from the Chandra archive. All 69 BCGs with radio AGN more luminous than 2x10^23^W/Hz at 1.4GHz are found to have X-ray cool cores. BCG cool cores can be divided into two classes: the large cool core (LCC) class and the corona class. As examples of the corona class, we also present detailed analyses of a BCG corona associated with a strong radio AGN (ESO 137-006 in A3627) and one of the faintest coronae known (NGC 4709 in the Centaurus cluster).
- ID:
- ivo://CDS.VizieR/J/A+A/455/813
- Title:
- BeppoSAX catalog of GRB X-ray afterglows
- Short Name:
- J/A+A/455/813
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the catalog of X-ray afterglow observed by BeppoSAX from the launch of the satellite to the end of the mission. Thirty-three X-ray afterglows out of 39 observations were securely identified based on their fading behavior. We have extracted the continuum parameters (decay index, spectral index, flux, absorption) for all available afterglows. We point out a possible correlation between the X-ray afterglow luminosity and the energy emitted during the prompt gamma-ray event.
- ID:
- ivo://CDS.VizieR/J/A+A/473/347
- Title:
- BeppoSAX complete catalogue of GRBs
- Short Name:
- J/A+A/473/347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the complete on-line catalogue of gamma-ray bursts observed by the two Wide Field Cameras on board BeppoSAX in the period 1996-2002. Our aim is to provide the community with the largest published data set of GRB's prompt emission X-ray light curves and other useful data.
- ID:
- ivo://CDS.VizieR/J/ApJS/180/192
- Title:
- BeppoSAX/GRBM {gamma}-ray Burst Catalog
- Short Name:
- J/ApJS/180/192
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the catalog of Gamma-Ray Bursts (GRBs) detected with the Gamma Ray Burst Monitor aboard the BeppoSAX satellite. It includes 1082 GRBs with 40-700keV fluences in the range from 1.3x10-7 to 4.5x10-4erg/cm^2^, and 40-700keV peak fluxes from 3.7x10-8 to 7.0x10-5erg/cm^2^/s. We report in the catalog some relevant parameters of each GRB.
