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91. 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.
92. 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.
93. 1000 brightest HIPASS galaxies catalog
ID:
ivo://CDS.VizieR/J/AJ/124/1954
Title:
1000 brightest HIPASS galaxies catalog
Short Name:
J/AJ/124/1954
Date:
21 Oct 2021
Publisher:
CDS
Description:
The HI Parkes All-Sky Survey (HIPASS) is a blind 21cm survey for extragalactic neutral hydrogen, covering the whole southern sky. The HIPASS Bright Galaxy Catalog (BGC) is a subset of HIPASS and contains the 1000 HI brightest (peak flux density) galaxies. Here we present the 138 HIPASS BGC galaxies that had no redshift measured prior to the Parkes multibeam HI surveys. Of the 138 galaxies, 87 are newly catalogued. Newly catalogued is defined as having no optical (or infrared) counterpart in the NASA/IPAC Extragalactic Database. Using the Digitized Sky Survey, we identify optical counterparts for almost half of the newly catalogued galaxies, which are typically of irregular or Magellanic morphological type. Several HI sources appear to be associated with compact groups or pairs of galaxies rather than an individual galaxy. The majority (57) of the newly catalogued galaxies lie within 10{deg} of the Galactic plane and are missing from optical surveys as a result of confusion with stars or dust extinction. This sample also includes newly catalogued galaxies first discovered by Henning et al. in the HI shallow survey of the zone of avoidance. The other 30 newly catalogued galaxies escaped detection because of their low surface brightness or optical compactness. Only one of these, HIPASS J0546-68, has no obvious optical counterpart, as it is obscured by the Large Magellanic Cloud. We find that the newly catalogued galaxies with |b|>10{deg} are generally lower in HI mass and narrower in velocity width compared with the total HIPASS BGC. In contrast, newly catalogued galaxies behind the Milky Way are found to be statistically similar to the entire HIPASS BGC. In addition to these galaxies, the HIPASS BGC contains four previously unknown HI clouds. Description:
94. Bright Extragalactic Radio Sources (1Jy)
ID:
ivo://CDS.VizieR/VIII/5
Title:
Bright Extragalactic Radio Sources (1Jy)
Short Name:
VIII/5
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog is a compilation of 518 extragalactic radio sources with flux densities greater than 1 Jy at 5 GHz. It contains sources from the NRAO-MPI 5-GHz Strong Source Surveys and from re-observation at 5 GHz of sources found in the Parkes 2.7-GHz surveys. All sources were found in 9.811 sr covered by the two surveys. This is essentially the whole sky, excluding the galactic plane (latitudes less than 10 degrees) and the Magellanic Clouds. The catalog includes radio flux densities, radio positions, object classes, visual magnitudes, redshifts, and spectral indices.
95. Bright Lyman-alpha emitters in MUSE/COSMOS field
ID:
ivo://CDS.VizieR/J/A+A/633/A159
Title:
Bright Lyman-alpha emitters in MUSE/COSMOS field
Short Name:
J/A+A/633/A159
Date:
21 Oct 2021
Publisher:
CDS
Description:
We search for the presence of bright Ly-alpha emitters among Spitzer SMUVS galaxies at z>2.9 making use of homogeneous MUSE spectroscopic data. Although these data only cover a small region of COSMOS, MUSE has the unique advantage of providing spectral information over the entire field, without the need of target pre-selection. This results in an unbiased detection of all the brightest Ly-alpha emitters among the SMUVS sources, which by design are stellar-mass selected galaxies. Within the studied area, ~14% of the SMUVS galaxies at z>2.9 have Ly-alpha fluxes F_{lambda}_>~7x10^-18^erg/s/cm^2^. These Ly-alpha emitters are characterized by three types of emission, 47% show a single line profile, 19% present a double peak or a blue bump and 31% show a red tail. One object (3%) shows both a blue bump and a red tail. We also investigate the spectral energy distribution (SED) properties of the SMUVS galaxies which are MUSE detected and which are not. After stellar-mass matching both populations, we find that the MUSE detected galaxies have generally lower extinction than SMUVS-only objects, while there is no clear intrinsic difference in the mass and age distributions of the two samples. For the MUSE-detected SMUVS galaxies, we compare the instantaneous SFR lower limit obtained from the Ly-alpha line with its past average derived from SED fitting, and find evidence for rejuvenation in some of our oldest objects. In addition, we study the spectra of those Ly-alpha emitters which are not detected in SMUVS in the same field. We find that the emission line profile shown are 67% a single line, 3% a blue bump and 20% a red tail profile. The difference in profile distribution could be ascribed to the fainter Ly-alpha luminosities of the MUSE sources not detected in SMUVS and an intrinsically different mass distribution. Finally, we search for the presence of galaxy associations using the spectral redshifts. MUSE's integral coverage reveals that these associations are 20 times more likely than what is derived from all the other existing spectral data in COSMOS, which is biased by target pre-selection.
96. Bright SHARC survey cluster catalog
ID:
ivo://CDS.VizieR/J/ApJS/126/209
Title:
Bright SHARC survey cluster catalog
Short Name:
J/ApJS/126/209
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Bright SHARC (Serendipitous High-Redshift Archival ROSAT Cluster) Survey, which is an objective search for serendipitously detected extended X-ray sources in 460 deep ROSAT PSPC pointings. The Bright SHARC Survey covers an area of 178.6 deg^2^ and has yielded 374 extended sources. We discuss the X-ray data reduction, the candidate selection and present results from our on-going optical follow-up campaign. The optical follow-up concentrates on the brightest 94 of the 374 extended sources and is now 97% complete. We have identified 37 clusters of galaxies, for which we present redshifts and luminosities. The clusters span a redshift range of 0.0696<z<0.83 and a luminosity range of 0.065<L_X_< 8.3x10^44^ergs/s [0.5-2.0keV] (assuming H_0_=50km/s/Mpc and q_0_=0.5). Twelve of the clusters have redshifts greater than z=0.3, eight of which are at luminosities brighter than L_X_=3x10^44^ergs/s. Seventeen of the 37 optically confirmed Bright SHARC clusters have not been listed in any previously published catalog. We also report the discovery of three candidate "fossil groups" of the kind proposed by Ponman et al. (1994Natur.369..462P)
97. BUDDA structural properties of galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/393/1531
Title:
BUDDA structural properties of galaxies
Short Name:
J/MNRAS/393/1531
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have performed 2D bulge/bar/disc decompositions using g, r and i-band images of a representative sample of nearly 1000 galaxies from the Sloan Digital Sky Survey. We show that the Petrosian concentration index is a better proxy for the bulge-to-total ratio than the global Sersic index. We show that pseudo-bulges can be distinguished from classical bulges as outliers in the Kormendy relation. We provide the structural parameters and distributions of stellar masses of ellipticals, classical bulges, pseudo-bulges, discs and bars, and find that 32% of the total stellar mass in massive galaxies in the local universe is contained in ellipticals, 36% in discs, 25% in classical bulges, 3% in pseudo-bulges and 4% in bars.
98. Bulge+disk decompositions of SDSS galaxies
ID:
ivo://CDS.VizieR/J/ApJS/196/11
Title:
Bulge+disk decompositions of SDSS galaxies
Short Name:
J/ApJS/196/11
Date:
21 Oct 2021
Publisher:
CDS
Description:
We perform two-dimensional, point-spread-function-convolved, bulge+disk decompositions in the g and r bandpasses on a sample of 1123718 galaxies from the Legacy area of the Sloan Digital Sky Survey Data Release Seven. Four different decomposition procedures are investigated which make improvements to sky background determinations and object deblending over the standard SDSS procedures that lead to more robust structural parameters and integrated galaxy magnitudes and colors, especially in crowded environments. We use a set of science-based quality assurance metrics, namely, the disk luminosity-size relation, the galaxy color-magnitude diagram, and the galaxy central (fiber) colors to show the robustness of our structural parameters. The best procedure utilizes simultaneous, two-bandpass decompositions. Bulge and disk photometric errors remain below 0.1mag down to bulge and disk magnitudes of g~19 and r~18.5. We also use and compare three different galaxy fitting models: a pure Sersic model, an n_b_=4 bulge+disk model, and a Sersic (free n_b_) bulge+disk model. The most appropriate model for a given galaxy is determined by the F-test probability. All three catalogs of measured structural parameters, rest-frame magnitudes, and colors are publicly released here.
99. Calern Observatory absolute declinations
ID:
ivo://CDS.VizieR/J/A+AS/137/269
Title:
Calern Observatory absolute declinations
Short Name:
J/A+AS/137/269
Date:
21 Oct 2021
Publisher:
CDS
Description:
A regular observational programme with a photoelectric astrolabe have been performed at ``Observatoire du Calern" (Observatoire de la Cote d'Azur, OCA, {phi}=+43{deg}44'55.011"; {lambda}=-0^h^27^m^42.44^s^, Calern, Caussols, France) for the last twenty years. It has been almost fully automatized between 1984 and 1987. Since 1988 the photoelectric astrolabe was used without any modification. In addition to determining the daily orientation of the local vertical, the yearly analysis of the residuals permits to derive corrections to the used star catalogue Vigouroux et al. (1992A&AS...96..477V). A global reduction method was applied for the ASPHO observations. The new form of the equations Martin & Leister (1997A&AS..126..169M) give us the possibility of using the entire set of the observing program using data taken at two zenith distances (30{deg} and 45{deg}). The program contains about 41648 stars' transits of 269 different stars taken at ``Observatoire du Calern" (OCA). The reduction was based on the HIPPARCOS system. We discuss the possibility of computing absolute declinations through stars belonging simultaneously to the 30{deg} and 45{deg} zenith distances programmes. The absolute declination corrections were determined for 185 stars with precision of 0.027" and the value of the determined equator correction is -0.018"+/-0.005". The instrumental effects were also determined. The mean epoch is 1995.29.
100. Calibrator stars for 200m baseline interferometry
ID:
ivo://CDS.VizieR/J/A+A/433/1155
Title:
Calibrator stars for 200m baseline interferometry
Short Name:
J/A+A/433/1155
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of reference stars suitable for calibrating infrared interferometric observations. In the K band, visibilities can be calibrated with a precision of 1% on baselines up to 200 meters for the whole sky, and up to 300 meters for some part of the sky. This work, extending to longer baselines a previous catalog compiled by Borde et al. (2002, Cat. <J/A+A/393/183>), is particularly well adapted to hectometric-class interferometers. We use the absolute spectro-photometric calibration method introduced by Cohen et al. (1999AJ....117.1864C) to derive the angular diameters of our new set of stars.

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