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- ID:
- ivo://CDS.VizieR/J/ApJS/181/605
- Title:
- Catalog of X-ray sources in NGC 4278
- Short Name:
- J/ApJS/181/605
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the properties of the discrete X-ray sources detected in our monitoring program of the globular cluster (GC) rich elliptical galaxy, NGC 4278, observed with Chandra ACIS-S in six separate pointings, resulting in a co-added exposure of 458ks. From this deep observation, 236 sources have been detected within the region overlapped by all observations, 180 of which lie within the D25 ellipse of the galaxy. These 236 sources range in L_X_ from 3.5x10^36^erg/s (with 3{sigma} upper limit <=1x10^37^erg/s) to ~2x10^40^erg/s, including the central nuclear source which has been classified as a LINER. From optical data, 39 X-ray sources have been determined to be coincident with a GC, these sources tend to have high X-ray luminosity, with 10 of these sources exhibiting L_X_>1x10^38^erg/s. From X-ray source photometry, it has been determined that the majority of the 236 point sources that have well-constrained colors have values that are consistent with typical low-mass X-ray binary spectra, with 29 of these sources expected to be background objects from the log N-log S relation. There are 103 sources in this population that exhibit long-term variability, indicating that they are accreting compact objects. Three of these sources have been identified as transient candidates, with a further three possible transients. Spectral variations have also been identified in the majority of the source population, where a diverse range of variability has been identified, indicating that there are many different source classes located within this galaxy.
- ID:
- ivo://CDS.VizieR/J/ApJS/179/142
- Title:
- Catalog of X-ray sources in NGC 3379
- Short Name:
- J/ApJS/179/142
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the properties of the discrete X-ray sources detected in our monitoring program of the 'typical' elliptical galaxy, NGC 3379, observed with Chandra ACIS-S in five separate pointings, resulting in a co-added exposure of 324ks. From this deep observation, 132 sources have been detected within the region overlapped by all observations, 98 of which lie within the D_25_ ellipse of the galaxy. These 132 sources range in L_X_ from 6x10^35^erg/s (with 3{sigma} upper limit <=4x10^36^erg/s) to ~2x10^39^erg/s, including one source with L_X_>1x10^39^erg/s, which has been classified as an ULX. From optical data, 10 X-ray sources have been determined to be coincident with a globular cluster, these sources tend to have high X-ray luminosity, with three of these sources exhibiting L_X_>1x10^38^erg/s. From X-ray source photometry, it has been determined that the majority of the 132 sources that have well constrained colors, have values that are consistent with typical LMXB spectra. In addition to this, a subpopulation of 10 sources has been found to exhibit very hard spectra and it is expected that most of these sources are absorbed background AGN. There are 64 sources in this population that exhibit long-term variability, indicating that they are accreting compact objects. Five of these sources have been identified as transient candidates, with a further 3 possible transients. Spectral variations have also been identified in the majority of the source population, where a diverse range of variability has been identified, indicating that there are many different source classes located within this galaxy.
- ID:
- ivo://CDS.VizieR/J/ApJ/621/104
- Title:
- Catalog of X-ray sources in the CYDER fields
- Short Name:
- J/ApJ/621/104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from the Calan-Yale Deep Extragalactic Research (CYDER) survey. The main goal of this survey is to study serendipitous X-ray sources detected by Chandra in an intermediate flux range (10^-15^ to 10^-12^ergs/s) that comprises most of the X-ray background. A total of 267 X-ray sources spread over five archived fields were detected.
- ID:
- ivo://CDS.VizieR/J/ApJ/796/105
- Title:
- Catalog of X-ray sources in the NARCS
- Short Name:
- J/ApJ/796/105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 1415 X-ray sources identified in the Norma Arm Region Chandra Survey (NARCS), which covers a 2{deg}x0.8{deg} region in the direction of the Norma spiral arm to a depth of ~20 ks. Of these sources, 1130 are point-like sources detected with >=3{sigma} confidence in at least one of three energy bands (0.5-10, 0.5-2, and 2-10 keV), five have extended emission, and the remainder are detected at low significance. Since most sources have too few counts to permit individual classification, they are divided into five spectral groups defined by their quantile properties. We analyze stacked spectra of X-ray sources within each group, in conjunction with their fluxes, variability, and infrared counterparts, to identify the dominant populations in our survey. We find that ~50% of our sources are foreground sources located within 1-2 kpc, which is consistent with expectations from previous surveys. Approximately 20% of sources are likely located in the proximity of the Scutum-Crux and near Norma arm, while 30% are more distant, in the proximity of the far Norma arm or beyond. We argue that a mixture of magnetic and nonmagnetic cataclysmic variables dominates the Scutum-Crux and near Norma arms, while intermediate polars and high-mass stars (isolated or in binaries) dominate the far Norma arm. We also present the cumulative number count distribution for sources in our survey that are detected in the hard energy band. A population of very hard sources in the vicinity of the far Norma arm and active galactic nuclei dominate the hard X-ray emission down to f_X_~10^-14^ erg/cm^2^/s, but the distribution curve flattens at fainter fluxes. We find good agreement between the observed distribution and predictions based on other surveys.
- ID:
- ivo://CDS.VizieR/J/A+AS/139/555
- Title:
- Catalogue and Bibliography of UV Cet stars
- Short Name:
- J/A+AS/139/555
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This new catalogue of flare stars includes 463 objects. It contains astrometric, spectral and photometric data as well as information on the infrared, radio and X-ray properties and general stellar parameters. From the total reference list of about 3400 articles, partial lists selected by objects, authors, key words and by any pairs of these criteria can be obtained.
- ID:
- ivo://CDS.VizieR/J/A+A/405/5
- Title:
- Catalogue of ISM content of normal galaxies
- Short Name:
- J/A+A/405/5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled a catalogue of the gas content for a sample of 1916 galaxies, considered to be a fair representation of normality. The definition of a normal galaxy adopted in this work implies that we have purposely excluded from the catalogue galaxies having distorted morphology (such as interaction bridges, tails or lopsidedness) and/or any signature of peculiar kinematics (such as polar rings, counterrotating disks or other decoupled components). In contrast, we have included systems hosting active galactic nuclei (AGN) in the catalogue. This catalogue revises previous compendia on the ISM content of galaxies published by Bregman et al. (1992ApJ...387..484B) and Casoli et al. (1998A&A...331..451C), and compiles data available in the literature from several small samples of galaxies. Masses for warm dust, atomic and molecular gas, as well as X-ray luminosities have been converted to a uniform distance scale taken from the Catalogue of Principal Galaxies (PGC). We have used two different normalization factors to explore the variation of the gas content along the Hubble sequence: the blue luminosity (LB) and the square of linear diameter (D_25_^2^). Our catalogue significantly improves the statistics of previous reference catalogues and can be used in future studies to define a template ISM content for normal galaxies along the Hubble sequence.
- ID:
- ivo://CDS.VizieR/J/A+A/316/147
- Title:
- Catalogue of ROSAT White Dwarfs
- Short Name:
- J/A+A/316/147
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table1 lists all white dwarf stars, both previously-catalogued and newly discovered, which have been detected in the ROSAT All-Sky Survey. The positions and count rates of the X-ray sources associated with each star are given, as well as spectral types and other star names for those stars which have been previously catalogued. Table2 lists distances estimated via Balmer line profile fitting, corrected (for IS absorption) X-ray luminosities, and each star's contribution to the X-ray luminosity function for all DA white dwarfs which were detected in the ROSAT All-Sky Survey.
- ID:
- ivo://CDS.VizieR/VII/173
- Title:
- Catalogue of Seyfert Galaxies
- Short Name:
- VII/173
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A list of 959 Seyfert galaxies whose data were obtained up to the beginning of 1987 is compiled. Coordinates, redshifts, UBVR-photoelectric magnitudes, absolute magnitudes, morphological types, fluxes in H and [OIII] 5007, JHKLN-fluxes, far-infrared (IRAS) fluxes, radio-fluxes at 6 and 11 centimeters, monochromatic X-ray fluxes in 0.3-3.5 and 2-10 keV and some other data are presented in six Tables. This Catalogue data may be used as basic ones for some statistical investigations. References contain 957 entries.
- ID:
- ivo://CDS.VizieR/V/90
- Title:
- Catalogue of X-Ray Binaries
- Short Name:
- V/90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The objects described in this catalog are X-Ray binaries, i.e., semi-detached binary stars in which matter is transferred from a usually more or less normal star to a neutron star or black hole. Thus, cataclysmic variables are not included. The tables provide basic information of the systems as well as selected references. The tables contain 124 low-mass and 69 high mass X-ray binaries.
