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1591. BOSS narrow CIV absorption lines. I. zem<=2.4
ID:
ivo://CDS.VizieR/J/ApJS/210/7
Title:
BOSS narrow CIV absorption lines. I. zem<=2.4
Short Name:
J/ApJS/210/7
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have assembled absorption systems by visually identifying CIV {lambda}{lambda}1548, 1551 absorption doublets in the quasar spectra of the Baryon Oscillation Spectroscopic Survey (BOSS) one by one. This paper is the first of the series of work. In this paper, we focus on quasars with relatively low redshifts and high signal-to-noise ratio spectra, and hence we limit our analysis to quasars with z_em_<=2.4 and to doublets with W_r_{lambda}1548>=0.2{AA}. Out of the more than 87000 quasars in Data Release 9, we limit our search to 10121 quasars that have the appropriate redshifts and spectra with high enough signal-to-noise ratios to identify narrow CIV absorption lines. Among them, 5442 quasars are detected to have at least one CIV {lambda}{lambda}1548, 1551 absorption doublet. We obtain a catalog containing 8368 CIV {lambda}{lambda}1548, 1551 absorption systems, whose redshifts are within z_abs_=1.4544-2.2805. In this catalog, about 33.7% absorbers have 0.2{AA}<=W_r_{lambda}1548<0.5{AA}, about 45.9% absorbers have 0.5{AA}<=W_r_{lambda}1548<1.0{AA}, about 19.2% absorbers have 1.0{AA}<=W_r_{lambda}1548<2.0{AA}, and about 1.2% absorbers have W_r_{lambda}1548>=2.0{AA}.
1592. BOSS: quasar luminosity function
ID:
ivo://CDS.VizieR/J/ApJ/773/14
Title:
BOSS: quasar luminosity function
Short Name:
J/ApJ/773/14
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new measurement of the optical quasar luminosity function (QLF), using data from the Sloan Digital Sky Survey-III: Baryon Oscillation Spectroscopic Survey (SDSS-III: BOSS). From the SDSS-III Data Release Nine, a uniform sample of 22301 i<~21.8 quasars are selected over an area of 2236deg^2^, with confirmed spectroscopic redshifts between 2.2<z<3.5, filling in a key part of the luminosity-redshift plane for optical quasar studies. The completeness of the survey is derived through simulated quasar photometry, and this completeness estimate is checked using a sample of quasars selected by their photometric variability within the BOSS footprint. We investigate the level of systematics associated with our quasar sample using the simulations, in the process generating color-redshift relations and a new quasar K-correction. We probe the faint end of the QLF to M_i_(z=2.2){approx}-24.5 and see a clear break in the QLF at all redshifts up to z=3.5. A log-linear relation (in log{Phi}*-M*) for a luminosity evolution and density evolution model is found to adequately describe our data within the range 2.2<z<3.5; across this interval the break luminosity increases by a factor of ~2.6 while {Phi}* declines by a factor of ~8. At z<~2.2 our data are reasonably well fit by a pure luminosity evolution model, and only a weak signature of "AGN downsizing" is seen, in line with recent studies of the hard X-ray luminosity function. We compare our measured QLF to a number of theoretical models and find that models making a variety of assumptions about quasar triggering and halo occupation can fit our data over a wide range of redshifts and luminosities.
1593. Box- and peanut-shaped bulges. I.
ID:
ivo://CDS.VizieR/J/A+AS/145/405
Title:
Box- and peanut-shaped bulges. I.
Short Name:
J/A+AS/145/405
Date:
21 Oct 2021
Publisher:
CDS
Description:
NIR observations reveal that dust extinction does almost not influence the shape of bulges. There is no substantial difference between the shape of bulges in the optical and in the NIR. Our analysis reveals that 45% of all bulges are box- and peanut-shaped (b/p). The frequency of b/p bulges for all morphological types from S0 to Sd is >40%. In particular, this is for the first time that such a large frequency of b/p bulges is reported for galaxies as late as Sd. The fraction of the observed b/p bulges is large enough to explain the origin of b/p bulges by a barred potential (Luetticke et al., 2000, A&A, accepted).
1594. Boxy/peanut-shaped bulges in barred galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/468/2058
Title:
Boxy/peanut-shaped bulges in barred galaxies
Short Name:
J/MNRAS/468/2058
Date:
21 Oct 2021
Publisher:
CDS
Description:
From a sample of 84 local barred, moderately inclined disc galaxies, we determine the fraction that hosts boxy or peanut-shaped (B/P) bulges (the vertically thickened inner parts of bars). We find that the frequency of B/P bulges in barred galaxies is a very strong function of stellar mass: 79 per cent of the bars in galaxies with log (M*/M_{sun}_)w>=10.4 have B/P bulges, while only 12 per cent of those in lower mass galaxies do. (We find a similar dependence in data published by Yoshino & Yamauchi for edge-on galaxies.) There are also strong trends with other galaxy parameters - e.g. Hubble type: 77 per cent of S0-Sbc bars, but only 15 per cent of Sc-Sd bars, have B/P bulges - but these appear to be side effects of the correlations of these parameters with stellar mass. In particular, despite indications from models that a high gas content can suppress bar buckling, we find no evidence that the (atomic) gas mass ratio M_HI+He_/M* affects the presence of B/P bulges, once the stellar-mass dependence is controlled for. The semimajor axes of B/P bulges range from one-quarter to three-quarters of the full bar size, with a mean of R_box_/L_bar_=0.42+/-0.09 and R_box_/a_{epsilon}_=0.53+/-0.12 (where R_box_ is the size of the B/P bulge and a_{epsilon}_ and L_bar_ are lower and upper limits on the size of the bar).
1595. B photometry of M31 variable star candidates
ID:
ivo://CDS.VizieR/J/AJ/129/2663
Title:
B photometry of M31 variable star candidates
Short Name:
J/AJ/129/2663
Date:
21 Oct 2021
Publisher:
CDS
Description:
A search for variable stars is performed using two epochs of Hubble Space Telescope Advanced Camera for Surveys imaging data for a 9.28arcmin^2^ portion of M31. This data set reveals 254 sources that vary by at least 4{sigma} between epochs. The positions and two-epoch B-band (equivalent) photometry of these sources are presented.
1596. B2 0258+35 polarisation images
ID:
ivo://CDS.VizieR/J/A+A/622/A209
Title:
B2 0258+35 polarisation images
Short Name:
J/A+A/622/A209
Date:
21 Oct 2021
Publisher:
CDS
Description:
The contribution of active galactic nuclei to the magnetisation of the Universe can be constrained by knowing their duty cycles, jet and magnetic field morphologies, and the physical processes dominating their interaction with the surrounding environment. The magnetic field morphology and strength of radio lobes of AGN has an influence on the mechanisms for the propagation of cosmic rays into intergalactic space. Using the source B2 0258+35 we want to investigate the interaction of its radio lobes with the surrounding environment and examine the underlying physical effects. Published HI and radio continuum data at {lambda}21cm were combined with newly reduced archival Westerbork Radio Synthesis Telescope polarisation data at the same wavelength to investigate the polarised emission in the radio lobes of B2 0258+35. We assumed energy equipartition between the cosmic rays and the magnetic field to calculate their pressure and investigate the physical processes leading to the detected emission. We detected a unique S-shaped diffuse polarised structure. The lobes have a pressure of p=1.95+/-0.4x10^-14^dyn/cm^2^. The calculated total magnetic field strengths are low (B_eq_=1.21+/-0.12uG). We observe depolarisation in the northern lobe, which might originate from the HI-disc in the foreground. In addition we see an anti-correlation between the pressure and the fractional polarisation along the S-shaped structure. Therefore we consider magnetic draping and magnetic field compression as possible effects that might have created the observed S-shape. Our results suggest that magnetic draping can be effectively used to explain the observed polarised structures. This is likely due to the combination of a relatively low magnetic field strength, enabling super-Alfvenic motion of the rising lobes (with M_A_=2.47-3.50), and the coherency of the surrounding magnetic field. Moreover, the draped layer tends to suppress any mixing of the material between the radio lobes and the surrounding environment, but can enhance the mixing and re-acceleration efficiencies inside the lobes, providing an explanation for the average flat spectral index observed in the lobes.
1597. BRAVA Catalog
ID:
ivo://irsa.ipac/BRAVA/Catalog
Title:
BRAVA Catalog
Short Name:
BRAVA Catalog
Date:
01 Oct 2018 20:27:21
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The Bulge Radial Velocity Assay (BRAVA) consists of spectra of approximately 8500 red giants in the Galactic bulge.
1598. Breaks in disc galaxy abundance gradients
ID:
ivo://CDS.VizieR/J/A+A/608/A127
Title:
Breaks in disc galaxy abundance gradients
Short Name:
J/A+A/608/A127
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine the relation between breaks in the surface brightness profiles and radial abundance gradients within the optical radius in the discs of 134 spiral galaxies from the CALIFA survey. The distribution of the radial abundance (in logarithmic scale) in each galaxy was fitted by simple and broken linear relations. The surface brightness profile was fitted assuming pure and broken exponents for the disc. We find that the maximum absolute difference between the abundances in a disc given by broken and pure linear relations is less than 0.05dex in the majority of our galaxies and exceeds the scatter in abundances for 26 out of 134 galaxies considered. The scatter in abundances around the broken linear relation is close (within a few percent) to that around the pure linear relation. The breaks in the surface brightness profiles are more prominent. The scatter around the broken exponent in a number of galaxies is lower by a factor of two or more than that around the pure exponent. The shapes of the abundance gradients and surface brightness profiles within the optical radius in a galaxy may be different. A pure exponential surface brightness profile may be accompanied by a broken abundance gradient and vise versa. There is no correlation between the break radii of the abundance gradients and surface brightness profiles. Thus, a break in the surface brightness profile does not need to be accompanied by a break in the abundance gradient.
1599. Breaks in surf. brightness prof. of galaxy disks
ID:
ivo://CDS.VizieR/J/A+A/625/A36
Title:
Breaks in surf. brightness prof. of galaxy disks
Short Name:
J/A+A/625/A36
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a sample of 175 low-inclination galaxies from the S^4^G, we investigate the origins of up-bending (Type III) breaks in the 3.6{mu}m surface brightness profiles of disk galaxies. We reanalyzed a sample of previously identified Type III disk break-hosting galaxies using a new, unbiased break-finding algorithm, which uncovered many new, sometimes subtle disk breaks across the whole sample. We classified each break by its likely origin through close examination of the galaxy images across wavelengths, and compare samples of galaxies separated by their outermost identified break types in terms of their stellar populations and local environments. We find that more than half of the confirmed Type III breaks in our sample can be attributed to morphological asymmetry in the host galaxies. As these breaks are mostly an artifact of the azimuthal averaging process, their status as physical breaks is questionable. Such galaxies occupy some of the highest density environments in our sample, implying that much of this asymmetry is the result of tidal disturbance. We also find that Type III breaks related to extended spiral arms or star formation often host down-bending (Type II) breaks at larger radius which were previously unidentified. Such galaxies reside in the lowest density environments in our sample, in line with previous studies that found a lack of Type II breaks in clusters. Galaxies occupying the highest density environments most often show Type III breaks associated with outer spheroidal components. We find that Type III breaks in the outer disks of galaxies arise most often through environmental influence: either tidal disturbance (resulting in disk asymmetry) or heating through, for example, galaxy harrassment (leading to spheroidal components). Galaxies hosting the latter break types also show bimodal distributions in central g-r color and morphological type, with more than half of such galaxies classified as Sa or earlier; this suggests these galaxies may be evolving into early-type galaxies. By contrast, we find that Type III breaks related to apparently secular features (e.g., spiral arms) may not truly define their hosts' outer disks, as often in such galaxies additional significant breaks can be found at larger radius. Given this variety in Type III break origins, we recommend in future break studies making a more detailed distinction between break subtypes when seeking out, for example, correlations between disk breaks and environment, to avoid mixing unlike physical phenomena.
1600. Brera Multi-scale Wavelet Chandra Source Catalog
ID:
ivo://nasa.heasarc/bmwchancat
Title:
Brera Multi-scale Wavelet Chandra Source Catalog
Short Name:
BMWCHANCAT
Date:
18 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains the BMW-Chandra source catalog drawn from essentially all Chandra ACIS-I pointed observations with an exposure time in excess of 10 ks that were public as of March 2003 (136 observations). Using the wavelet detection algorithm developed by Lazzati et al. (1999ApJ...524..414) and Campana et al. (1999ApJ...524..423C), which can characterize both point-like and extended sources, the authors identified 21325 sources. Among them, 16758 are serendipitous, i.e. not associated with the targets of the pointings, and do not require a non-automated analysis. This makes this catalog the largest compilation of Chandra sources as of the date of publication of this catalog (August 2008). The 0.5 - 10 keV absorption corrected fluxes of these sources range from ~3 x 10&lt;sup&gt;-16&lt;/sup&gt; to 9 x 10&lt;sup&gt;-12&lt;/sup&gt; erg/cm&lt;sup&gt;2&lt;/sup&gt;/s with a median of 7 x 10&lt;sup&gt;-15&lt;/sup&gt; erg/cm&lt;sup&gt;2&lt;/sup&gt;/s. The catalog consists of count rates and relative errors in three energy bands (total, 0.5 - 7 keV; soft, 0.5 - 2 keV; and hard, 2 - 7 keV), and source positions relative to the highest signal-to-noise detection among the three bands. The wavelet algorithm also provides an estimate of the extension of the source. The authors include information drawn from the headers of the original files, as well, and extracted source counts in four additional energy bands, SB1 (0.5 - 1 keV), SB2 (1 - 2 keV), HB1 (2 - 4 keV), and HB2 (4 - 7 keV). They computed the sky coverage for the full catalog and for a subset at high Galactic latitude (|b| &gt; 20 degrees). The complete catalog provides a sky coverage in the soft band (0.5 - 2 keV, S/N = 3) of ~8 deg&lt;sup&gt;2&lt;/sup&gt; at a limiting flux of 10&lt;sup&gt;-13&lt;/sup&gt; erg/cm&lt;sup&gt;2&lt;/sup&gt;/s, and ~2 deg&lt;sup&gt;2&lt;/sup&gt; at a limiting flux of ~10&lt;sup&gt;-15&lt;/sup&gt; erg/cm&lt;sup&gt;2&lt;/sup&gt;/s. The total numbers of matches with the FIRST, IRASPSC, 2MASS, and GSC2 catalogs obtained after a closest-distance selection are 13, 87, 6700, and 4485, respectively. This table was created by the HEASARC in September 2008 based on the CDS table J/A+A/488/1221 file catalog.dat. The catalog version is BMC 1.0.1F. All sources in this version of the catalog were from observations in POINTING and TIMED ACIS read modes. This is a service provided by NASA HEASARC .

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