- ID:
- ivo://CDS.VizieR/J/MNRAS/470/512
- Title:
- INTEGRAL 14-year Galactic hard X-ray sources
- Short Name:
- J/MNRAS/470/512
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) continues to successfully work in orbit after its launch in 2002. The mission provides the deepest ever survey of hard X-ray sources throughout the Galaxy at energies above 20keV. We report on a catalogue of new hard X-ray source candidates based on the latest sky maps comprising 14yr of data acquired with the IBIS telescope onboard INTEGRAL in the Galactic Plane (|b|<17.5{deg}). The current catalogue includes in total 72 hard X-ray sources detected at S/N>4.7{sigma} and not known to previous INTEGRAL surveys. Among them, 31 objects have also been detected in the on-going all-sky survey by the BAT telescope of the Swift observatory. For 26 sources on the list, we suggest possible identifications: 21 active galactic nuclei, two cataclysmic variables, two isolated pulsars or pulsar wind nebulae and one supernova remnant; 46 sources from the catalogue remain unclassified.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/448/3766
- Title:
- INTEGRAL 11-year hard X-ray survey
- Short Name:
- J/MNRAS/448/3766
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an all-sky survey, performed with data acquired by the Imager on-Board the INTEGRAL Satellite (IBIS) telescope on board the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) observatory over 11 years of operation, at energies above 100 keV. The catalogue of detected sources includes 132 objects. The statistical sample detected on the time-averaged 100-150 keV map at a significance above 5{sigma} contains 88 sources: 28 active galactic nuclei (AGNs), 38 low-mass X-ray binaries (LMXBs), 10 high-mass X-ray binaries (HMXBs) and 12 rotation-powered young X-ray pulsars. The catalogue also includes 15 persistent sources, which were registered at significance 4{sigma}<=S/N<5{sigma}, where S/N is the signal-to-noise ratio, but at the same time were firmly detected (>=12{sigma}) in the lower 17-60keV energy band. All registered sources are known X-ray emitters, which means that the catalogue has 100 percent purity in this respect. Additionally, 29 catalogued sources were detected significantly in different time slices of the survey. In the context of the survey, we present a hardness ratio for Galactic and extragalactic sources, an LMXB longitudinal asymmetry and a number-flux relation for non-blazar AGNs. At higher energies, in the 150-300keV energy band, 25 sources have been detected with S/N>=5{sigma}, including seven AGNs, 13 LMXBs, three HMXBs and two rotation-powered pulsars. Among LMXBs and HMXBs, we identified 12 black hole candidates (BHCs) and four neutron star (NS) binaries.
- ID:
- ivo://CDS.VizieR/J/ApJS/143/25
- Title:
- Intermediate-luminosity X-ray objects catalog
- Short Name:
- J/ApJS/143/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- ROSAT, and now Chandra, X-ray images allow studies of extranuclear X-ray point sources in galaxies other than our own. X-ray observations of normal galaxies with ROSAT and Chandra have revealed that off-nuclear, compact, intermediate-luminosity (L_X_[2-10keV]>=10^39^erg/s) X-ray objects (IXOs, a.k.a. ULXs [ultraluminous X-ray sources]) are quite common. Here we present a catalog and finding charts for 87 IXOs in 54 galaxies, derived from all of the ROSAT HRI imaging data for galaxies with cz<=5000km/s from the Third Reference Catalog of Bright Galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/733/113
- Title:
- IRAC observations of IC 1795
- Short Name:
- J/ApJ/733/113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a deep Spitzer/Infrared Array Camera (IRAC) survey of the OB association IC 1795 carried out to investigate the evolution of protoplanetary disks in regions of massive star formation. Combining Spitzer/IRAC data with Chandra/Advanced CCD Imaging Spectrometer observations, we find 289 cluster members. An additional 340 sources with an infrared excess, but without X-ray counterpart, are classified as cluster member candidates. Both surveys are complete down to stellar masses of about 1M_{sun}_. We present pre-main-sequence isochrones computed for the first time in the Spitzer/IRAC colors. The age of the cluster, determined via the location of the Class III sources in the [3.6]-[4.5]/[3.6] color-magnitude diagram, is in the range of 3-5Myr. As theoretically expected, we do not find any systematic variation in the spatial distribution of disks within 0.6pc of either O-type star in the association. However, the disk fraction in IC 1795 does depend on the stellar mass: sources with masses >2M_{sun}_ have a disk fraction of ~20%, while lower mass objects (2-0.8M_{sun}_) have a disk fraction of ~50%. This implies that disks around massive stars have a shorter dissipation timescale.
- ID:
- ivo://CDS.VizieR/J/A+A/507/241
- Title:
- IR and 610MHz observations in MGRO J2019+37
- Short Name:
- J/A+A/507/241
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- MGROJ2019+37 is an unidentified extended source of very high energy gamma-rays originally reported by the Milagro Collaboration as the brightest TeV source in the Cygnus region. Its extended emission could be powered by either a single or several sources. The GeV pulsar AGL J2020.5+3653 discovered by AGILE and associated with PSR J2021+3651 could contribute to the emission from MGRO J2019+37. The aim of this paper is to identify radio and near-infrared sources in the field of the extended TeV source MGRO J2019+37, and study potential counterparts to explain its emission. We surveyed a region of about 6 square degrees with the Giant Metrewave Radio Telescope (GMRT) at the frequency 610MHz. We also observed the central square degree of this survey in the near-infrared Ks-band using the 3.5m telescope in Calar Alto. Archival X-ray observations of some specific fields are included. VLBI observations of an interesting radio source were performed. We explored possible scenarios to produce the multi-TeV emission from MGRO J2019+37 and studied which of the sources could be the main particle accelerator.
- ID:
- ivo://CDS.VizieR/J/ApJS/199/23
- Title:
- IR and UV star formation in ACCEPT BCGs
- Short Name:
- J/ApJS/199/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present infrared (IR) and ultraviolet (UV) photometry for a sample of brightest cluster galaxies (BCGs). The BCGs are from a heterogeneous but uniformly characterized sample, the Archive of Chandra Cluster Entropy Profile Tables (ACCEPT), of X-ray galaxy clusters from the Chandra X-ray telescope archive with published gas temperature, density, and entropy profiles. We use archival Galaxy Evolution Explorer (GALEX), Spitzer Space Telescope, and Two Micron All Sky Survey (2MASS) observations to assemble spectral energy distributions (SEDs) and colors for BCGs. We establish a mean near-UV (NUV) to 2MASS K color of 6.59+/-0.34 for quiescent BCGs. We use this mean color to quantify the UV excess associated with star formation in the active BCGs. We use both fits to a template of an evolved stellar population and library of starburst models and mid-IR star formation relations to estimate the obscured star formation rates (SFRs). We present IR and UV photometry and estimated equivalent continuous SFRs for a sample of BCGs.
- ID:
- ivo://CDS.VizieR/J/ApJ/563/L49
- Title:
- IR counterpart of the X-ray pulsar 1E 2259+586
- Short Name:
- J/ApJ/563/L49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present near-infrared and optical observations of the field of the anomalous X-ray pulsar 1E 2259+586 taken with the Keck telescope. We derive a sub-arcsecond Chandra position and tie it to our optical reference frame using other stars in the field. We find a very faint source, K_S_=21.7+/-0.2mag, with a position coincident with the Chandra position. We argue that this is the counterpart. In the J, I, and R bands, we derive (2{sigma}) limits of 23.8, 25.6, and 26.4mag, respectively. As with 4U 0142+61, for which a counterpart has previously been found, our results are inconsistent with models in which the source is powered by accretion from a disk but may be consistent with the magnetar model.
- ID:
- ivo://CDS.VizieR/J/AJ/144/11
- Title:
- IR imaging, nuclear SEDs, Spitzer spectra of 22 AGNs
- Short Name:
- J/AJ/144/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-resolution mid-infrared (MIR) imaging, nuclear spectral energy distributions (SEDs), and archival Spitzer spectra for 22 low-luminosity active galactic nuclei (LLAGNs; L_bol_<~10^42^erg/s). Infrared (IR) observations may advance our understanding of the accretion flows in LLAGNs, the fate of the obscuring torus at low accretion rates, and, perhaps, the star formation histories of these objects. However, while comprehensively studied in higher-luminosity Seyferts and quasars, the nuclear IR properties of LLAGNs have not yet been well determined. We separate the present LLAGN sample into three categories depending on their Eddington ratio and radio emission, finding different IR characteristics for each class. (1) At the low-luminosity, low-Eddington-ratio (log L_bol_/L_Edd_< -4.6) end of the sample, we identify "host-dominated" galaxies with strong polycyclic aromatic hydrocarbon bands that may indicate active (circum-)nuclear star formation. (2) Some very radio-loud objects are also present at these low Eddington ratios. The IR emission in these nuclei is dominated by synchrotron radiation, and some are likely to be unobscured type 2 AGNs that genuinely lack a broad-line region. (3) At higher Eddington ratios, strong, compact nuclear sources are visible in the MIR images. The nuclear SEDs of these galaxies are diverse; some resemble typical Seyfert nuclei, while others lack a well-defined MIR "dust bump." Strong silicate emission is present in many of these objects. We speculate that this, together with high ratios of silicate strength to hydrogen column density, could suggest optically thin dust and low dust-to-gas ratios, in accordance with model predictions that LLAGNs do not host a Seyfert-like obscuring torus. We anticipate that detailed modeling of the new data and SEDs in terms of accretion disk, jet, radiatively inefficient accretion flow, and torus components will provide further insights into the nuclear structures and processes of LLAGNs.
- ID:
- ivo://CDS.VizieR/J/ApJ/761/184
- Title:
- IR luminosities for dusty AGNs and QSOs
- Short Name:
- J/ApJ/761/184
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Mid-infrared spectroscopic measurements from the Infrared Spectrometer (IRS) on Spitzer are given for 125 hard X-ray active galactic nuclei (AGNs; 14-195keV) from the Swift Burst Alert Telescope (BAT) sample and for 32 AGNs with black hole masses (BHMs) from reverberation mapping. The 9.7{mu}m silicate feature in emission or absorption defines an infrared AGN classification describing whether AGNs are observed through dust clouds, indicating that 55% of the BAT AGNs are observed through dust. The 100 most luminous type 1 quasars as measured in {nu}L_{nu}_(7.8{mu}m) are found by comparing Sloan Digital Sky Survey (SDSS) optically discovered quasars with photometry at 22{mu}m from the Wide-Field Infrared Survey Explorer (WISE), scaled to rest frame 7.8{mu}m using an empirical template determined from IRS spectra. The most luminous SDSS/WISE quasars have the same maximum infrared luminosities for all 1.5<z<5, reaching total infrared luminosity L_IR_=10^14.4^L_{sun}_. Comparing with dust-obscured galaxies from Spitzer and WISE surveys, we find no evidence of hyperluminous obscured quasars whose maximum infrared luminosities exceed the maximum infrared luminosities of optically discovered quasars. Bolometric luminosities L_bol_ estimated from rest-frame optical or ultraviolet luminosities are compared to L_IR_. For the local AGN, the median logL_IR_/L_bol_=-0.35, consistent with a covering factor of 45% for the absorbing dust clouds. For the SDSS/WISE quasars, the median logL_IR_/L_bol_=0.1, with extremes indicating that ultraviolet-derived L_bol_ can be seriously underestimated even for type 1 quasars.
- ID:
- ivo://CDS.VizieR/J/ApJ/652/1554
- Title:
- Iron in hot DA white dwarfs
- Short Name:
- J/ApJ/652/1554
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of the iron abundance pattern in hot, hydrogen-rich (DA) white dwarfs. The study is based on new and archival far-ultraviolet spectroscopy of a sample of white dwarfs in the temperature range 30000K<=Teff<=64000K. The spectra obtained with the Far Ultraviolet Spectroscopic Explorer, along with spectra obtained with the Hubble Space Telescope Imaging Spectrograph and the International Ultraviolet Explorer, sample FeIII-FeVI absorption lines, enabling a detailed iron abundance analysis over a wider range of effective temperatures than previously afforded.
