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- 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.
- ID:
- ivo://CDS.VizieR/J/ApJS/194/15
- Title:
- CCCP: Carina's diffuse X-ray emission
- Short Name:
- J/ApJS/194/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 1.42deg^2^ mosaic of diffuse X-ray emission in the Great Nebula in Carina from the Chandra X-ray Observatory Advanced CCD Imaging Spectrometer camera. After removing >14000 X-ray point sources from the field, we smooth the remaining unresolved emission, tessellate it into segments of similar apparent surface brightness, and perform X-ray spectral fitting on those tessellates to infer the intrinsic properties of the X-ray-emitting plasma. By modeling faint resolved point sources, we estimate the contribution to the extended X-ray emission from unresolved point sources and show that the vast majority of Carina's unresolved X-ray emission is truly diffuse. Line-like correlated residuals in the X-ray spectral fits suggest that substantial X-ray emission is generated by charge exchange at the interfaces between Carina's hot, rarefied plasma and its many cold neutral pillars, ridges, and clumps.
- ID:
- ivo://CDS.VizieR/J/AJ/155/58
- Title:
- 2006-2016 CCD photometry of V723 Cassiopeia
- Short Name:
- J/AJ/155/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometric data of the classical nova, V723 Cas (Nova Cas 1995), over a span of 10 years (2006 through 2016) taken with the 0.9 m telescope at Lowell Observatory, operated as the National Undergraduate Research Observatory (NURO) on Anderson Mesa near Flagstaff, Arizona. A photometric analysis of the data produced light curves in the optical bands (Bessel B, V, and R filters). The data analyzed here reveal an asymmetric light curve (steep rise to maximum, followed by a slow decline to minimum), the overall structure of which exhibits pronounced evolution including a decrease in magnitude from year to year, at the rate of ~0.15 mag/yr. We model these data with an irradiated secondary and an accretion disk with a hot spot using the eclipsing binary modeling program Nightfall. We find that we can model reasonably well each season of observation by changing very few parameters. The longitude of the hot spot on the disk and the brightness of the irradiated spot on the companion are largely responsible for the majority of the observed changes in the light curve shape and amplitude until 2009. After that, a decrease in the temperature of the white dwarf is required to model the observed light curves. This is supported by Swift/X-Ray Telescope observations, which indicate that nuclear fusion has ceased, and that V723 Cas is no longer detectable in the X-ray.
- ID:
- ivo://CDS.VizieR/J/AJ/127/1014
- Title:
- CCD UBVRIHa photometry in NGC 3603
- Short Name:
- J/AJ/127/1014
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present UBVRI and H{alpha} photometry of the extremely compact, starburst cluster NGC 3603. Ground-based images, Hubble Space Telescope (HST) archival data, as well as Chandra X-ray data have been used for this study. We present, for the first time, optical color-magnitude diagrams (CMDs) for the stars in the cluster core down to V=22mag. A well-defined main sequence (MS) as well as low-mass pre-main-sequence (PMS) stars can clearly be seen in the CMDs. This result confirms the finding by Eisenhauer et al. (1998ApJ...498..278E) that low-mass stars are forming in the starburst cluster. We also derive an age (1+/-1Myr) and distance of the cluster (V_0_-M_V_=14.2+/-0.2mag, i.e., d=6.9+/-0.6kpc).