- ID:
- ivo://CDS.VizieR/J/ApJ/613/279
- Title:
- ACS Virgo Cluster Survey. III. M87
- Short Name:
- J/ApJ/613/279
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ACIS instrument on board the Chandra X-Ray Observatory has been used to carry out the first systematic study of low-mass X-ray binaries (LMXBs) in M87, the giant elliptical galaxy near the dynamical center of the Virgo Cluster. These images - with a total exposure time of 154 ks - are the deepest X-ray observations yet obtained of M87. We identify 174 X-ray point sources, of which 150 are likely LMXBs.
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- ID:
- ivo://CDS.VizieR/J/ApJS/250/23
- Title:
- AstroSat/UVIT and Chandra X-ray sources in M31
- Short Name:
- J/ApJS/250/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An ultraviolet (UV) survey of M31 has been carried out during 2017-19 with the Ultra-Violet Imaging Telescope (UVIT) instrument on board the AstroSat Observatory. Here we match the M31 UVIT source catalog with the Chandra source catalog. We find 67 UVIT/Chandra sources detected in a varying number of UV and X-ray bands. The UV and X-ray photometry is analyzed using power-law and blackbody models. The X-ray types include 15 low-mass X-ray binaries (LMXBs) and five active galactic nuclei. Crossmatches with catalogs of stars, clusters, and other source types yield the following: 20 of the UVIT/Chandra sources match with M31 globular clusters, and nine with foreground stars. Three more globular clusters and two more foreground stars are consistent with the UVIT source positions although outside the Chandra match radius of 1". The UV emission of the UVIT/Chandra sources associated with globular clusters is consistent with emission from blue horizontal branch stars rather than from the X-ray source. The LMXBs in globular clusters are among the most luminous globular clusters in M31. Comparison with stellar evolutionary tracks shows that the UVIT/Chandra sources with high UV blackbody temperatures are consistent with massive (10-30M_{sun}_) stars in M31.
- ID:
- ivo://CDS.VizieR/J/MNRAS/388/1198
- Title:
- Be/X-ray binaries in Small Magellanic Cloud
- Short Name:
- J/MNRAS/388/1198
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The spectral distributions of Be/X-ray binaries in the Large Magellanic Cloud and Galaxy have been shown to differ significantly from the distribution of isolated Be stars in the Galaxy. Population synthesis models can explain this difference in spectral distributions through substantial angular momentum loss from the binary system. In this work, we explore the spectral distribution of Be/X-ray binaries in the Small Magellanic Cloud (SMC) using high signal-to-noise ratio spectroscopy of a sample of 37 optical counterparts to known X-ray pulsars. Our results show that the spectral distribution of Be/X-ray binaries in the SMC is consistent with that of the Galaxy, despite the lower metallicity environment of the SMC. This may indicate that, although the metallicity of the SMC is conducive to the formation of a large number of high-mass X-ray binaries, the spectral distribution of these systems is likely to be most strongly influenced by angular momentum losses during binary evolution, which are not particularly dependent on the local metallicity.
- ID:
- ivo://CDS.VizieR/J/A+A/587/A61
- Title:
- BlackCAT, stellar-mass BH in X-ray trans.
- Short Name:
- J/A+A/587/A61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- During the last ~50 years, the population of black hole candidates in X-ray binaries has increased considerably, with 59 Galactic objects being detected in transient low-mass X-ray binaries, as well as a few in persistent systems (including ~5 extragalactic binaries). We collect near-infrared, optical, and X-ray information spread over hundreds of references to study the population of black holes in X-ray transients as a whole. We present the most updated catalogue of black hole transients. This contains X-ray, optical, and near-infrared observations, together with their astrometric and dynamical properties. The catalogue provides new and useful information in both statistical and observational parameters and provides a thorough and complete overview of the black hole population in the Milky Way. Analysing the distances and spatial distribution of the observed systems, we estimate a total population of ~1300 Galactic black hole transients. This means that we have only discovered less than ~5% of the total Galactic distribution. The complete version of this catalogue will be continuously updated online and in the Virtual Observatory, including finding charts and data in other wavelengths.
- ID:
- ivo://CDS.VizieR/J/MNRAS/447/2059
- Title:
- Black hole binaries quasi-periodic oscillations
- Short Name:
- J/MNRAS/447/2059
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a systematic study of the orbital inclination effects on black hole transients fast time-variability properties. We have considered all the black hole binaries that have been densely monitored by the Rossi X-ray Timing Explorer satellite. We find that the amplitude of low-frequency quasi-periodic oscillations (QPOs) depends on the orbital inclination. Type-C QPOs are stronger for nearly edge-on systems (high inclination), while type-B QPOs are stronger when the accretion disc is closer to face-on (low inclination). Our results also suggest that the noise associated with type-C QPOs is consistent with being stronger for low-inclination sources, while the noise associated with type-B QPOs seems inclination independent. These results are consistent with a geometric origin of the type-C QPOs - for instance arising from relativistic precession of the inner flow within a truncated disc - while the noise would correspond to intrinsic brightness variability from mass accretion rate fluctuations in the accretion flow. The opposite behaviour of type-B QPOs - stronger in low-inclinations sources - supports the hypothesis that type-B QPOs are related to the jet, the power of which is the most obvious measurable parameter expected to be stronger in nearly face-on sources.
- ID:
- ivo://CDS.VizieR/J/MNRAS/466/1019
- Title:
- Bright HMXBs in THINGS galaxies
- Short Name:
- J/MNRAS/466/1019
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using a spectral analysis of bright Chandra X-ray sources located in 27 nearby galaxies and maps of star-formation rate (SFR) and ISM surface densities for these galaxies, we constructed the intrinsic X-ray luminosity function (XLF) of luminous high-mass X-ray binaries (HMXBs), taking into account absorption effects and the diversity of HMXB spectra. The XLF per unit SFR can be described by a power law dN/dlogL=2.0(L/10^39^erg/s)^(-0.6)^(M_{sun}_/yr)^-1^ from L=10^38^ to 10^40.5^erg/s, where L is the unabsorbed luminosity at 0.25-8 keV. The intrinsic number of luminous HMXBs per unit SFR is a factor of ~2.3 larger than the observed number reported before. The intrinsic XLF is composed of hard, soft and supersoft sources (defined here as those with the 0.25-2keV to 0.25-8keV flux ratio of <0.6, 0.6-0.95 and >0.95, respectively) in ~2:1:1 proportion. We also constructed the intrinsic HMXB XLF in the soft X-ray band (0.25-2keV). Here, the numbers of hard, soft and supersoft sources prove to be nearly equal. The cumulative present-day 0.25-2 keV emissivity of HMXBs with luminosities between 10^38^ and 10^40.5^erg/s is ~5x10^39^erg/s(M_{sun}_/yr)^-1^, which may be relevant for studying the X-ray preheating of the early Universe.
- ID:
- ivo://CDS.VizieR/J/A+A/574/A33
- Title:
- BVRI photometry of high-mass X-ray binaries
- Short Name:
- J/A+A/574/A33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometric observations of the field around the optical counterparts of high-mass X-ray binaries. Our aim is to study the long-term photometric variability in correlation with their X-ray activity and derive a set of secondary standard stars that can be used for time series analysis. We find that the donors in Be/X-ray binaries exhibit larger amplitude changes in the magnitudes and colours than those hosting a supergiant companion. The amplitude of variability increases with wavelength in Be/X-ray binaries and remains fairly constant in supergiant systems. When time scales of years are considered, a good correlation between the X-ray and optical variability is observed. The X-rays cease when optical brightness decreases. These results reflect the fact that the circumstellar disk in Be/X-ray binaries is the main source of both optical and X-ray variability. We also derive the colour excess, E(B-V), selecting data at times when the contribution of the circumstellar disk was supposed to be at minimum, and we revisit the distance estimates.
- ID:
- ivo://CDS.VizieR/V/99
- Title:
- Cataclysmic Binaries and LMXB Catalogue
- Short Name:
- V/99
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Cataclysmic Binaries are semi-detached binaries consisting of a white dwarf or a white dwarf precursor primary and a low-mass secondary which is filling its critical Roche lobe. The secondary is not necessarily unevolved, it may even be a highly evolved star as for example in the case of the AM CVn-type stars. Low-Mass X-Ray Binaries are semi-detached binaries consisting of either a neutron star or a black hole primary, and a low-mass secondary which is filling its critical Roche lobe. Related Objects are detached binaries consisting of either a white dwarf or a white dwarf precursor primary and of a low-mass secondary. The secondary may also be a highly evolved star. The catalogue lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components and other characteristic properties of 318 cataclysmic binaries, 47 low-mass X-ray binaries and 49 related objects with known or suspected orbital periods together with a comprehensive selection of the relevant recent literature. In addition the catalogue contains a list of references to published finding charts for 394 of the 414 objects. A cross-reference list of alias object designations concludes the catalogue. Literature published before 30 June 1997 has, as far as possible, been taken into account. This catalogue supersedes the 5th edition (catalogue <V/59>) and the updated list by Ritter and Kolb (1995; catalogue <V/82>).
- ID:
- ivo://CDS.VizieR/V/113D
- Title:
- Cataclysmic Binaries, LMXBs, and related objects
- Short Name:
- V/113D
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Cataclysmic Binaries are semi-detached binaries consisting of a white dwarf or a white dwarf precursor primary and a low-mass secondary which is filling its critical Roche lobe. The secondary is not necessarily unevolved, it may even be a highly evolved star as for example in the case of the AM CVn-type stars. Low-Mass X-Ray Binaries are semi-detached binaries consisting of either a neutron star or a black hole primary, and a low-mass secondary which is filling its critical Roche lobe. Related Objects are detached binaries consisting of either a white dwarf or a white dwarf precursor primary and of a low-mass secondary. The secondary may also be a highly evolved star. The catalogue lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components and other characteristic properties of 572 cataclysmic binaries, 80 low-mass X-ray binaries and 142 related objects with known or suspected orbital periods together with a comprehensive selection of the relevant recent literature. In addition the catalogue contains a list of references to published finding charts for 761 of the 794 objects. A cross-reference list of alias object designations concludes the catalogue. Literature published before 31 December 2004 has, as far as possible, been taken into account. This catalogue supersedes the 5th edition (catalogue <V/59>) and the updated lists by Ritter and Kolb (1995; catalogue <V/82>) (1998; catalogue <V/99>).
- ID:
- ivo://CDS.VizieR/B/cb
- Title:
- Cataclysmic Binaries, LMXBs, and related objects
- Short Name:
- B/cb
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)