- ID:
- ivo://CDS.VizieR/J/A+A/434/1125
- Title:
- B-type Supergiants in the SMC
- Short Name:
- J/A+A/434/1125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-resolution UCLES/AAT spectra are presented for nine B-type supergiants in the SMC, chosen on the basis that they may show varying amounts of nuclear-synthetically processed material mixed to their surface. These spectra have been analysed using a new grid of approximately 12000 non-LTE line blanketed TLUSTY model atmospheres to estimate atmospheric parameters and chemical composition.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/606/A8
- Title:
- Bubble HII region Sh2-39 (N5)
- Short Name:
- J/A+A/606/A8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Aiming at studying the physical properties of Galactic IR bubbles and to explore their impact in triggering massive star formation, we perform a multiwavelength analysis of the bubble HII region Sh2-39 (N5) and its environs. To analyze the molecular gas we use CO(3-2) and HCO^+^(4-3) line data obtained with the on-the-fly technique from the ASTE telescope. To study the distribution and physical characteristics of the dust, we make use of archival data from ATLASGAL, Herschel, and MSX, while the ionized gas was studied making use of an NVSS image. We use public WISE, Spitzer, and MSX point source catalogs to search for infrared candidate YSOs in the region. To investigate the stellar cluster [BDS2003] 6 we use IR spectroscopic data obtained with the ARCoIRIS spectrograph, mounted on Blanco 4-m Telescope at CTIO, and new available IR Ks band observations from the VVVeXtended ESO Public Survey (VVVX). The new ASTE observations allowed the molecular gas component in the velocity range from 30km/s to 46km/s, associated with Sh2-39, to be studied in detail. The morphology of the molecular gas suggests that the ionized gas is expanding against its parental cloud. We have identified four molecular clumps, that were likely formed by the expansion of the ionization front, and determined some of their physical and dynamical properties. Clumps having HCO^+^ and 870um counterparts show evidence of gravitational collapse. We identified several candidate YSOs across the molecular component. Their spatial distribution, as well as the fragmentation time derived for the collected layers of the molecular gas, suggest that massive star formation might have been triggered by the expansion of the nebula via the collect and collapse mechanism. The spectroscopical distance obtained for the stellar cluster [BDS2003] 6, placed over one of the collapsing clumps in the border of the HII region, reveals that this cluster is physically associated with the nebula and gives more support to the triggered massive star formation scenario. A radio continuum data analysis indicates that the nebula is older and expands at lower velocity than typical IR Galactic bubbles.
- ID:
- ivo://CDS.VizieR/J/ApJ/649/759
- Title:
- Bubbles in the galactic disk
- Short Name:
- J/ApJ/649/759
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A visual examination of the images from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) has revealed 322 partial and closed rings that we propose represent partially or fully enclosed three-dimensional bubbles. We argue that the bubbles are primarily formed by hot young stars in massive star formation regions. We have found an average of about 1.5 bubbles per square degree. About 25% of the bubbles coincide with known radio HII regions, and about 13% enclose known star clusters. It appears that B4B9 stars (too cool to produce detectable radio HII regions) probably produce about three-quarters of the bubbles in our sample, and the remainder are produced by young OB3 stars that produce detectable radio HII regions.
- ID:
- ivo://CDS.VizieR/J/ApJ/670/428
- Title:
- Bubbles in the galactic disk. II.
- Short Name:
- J/ApJ/670/428
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report 269 mid-infrared bubbles within 10{deg} of the Galactic center from visual inspection of the Spitzer GLIMPSE II Legacy Science program images. The surface density of bubbles is ~5deg^-2^ or about 3 times that detected in longitudes |l|=10{deg}-65{deg}, because the inner 10{deg} of longitude were more thoroughly searched for small bubbles. There is a gradient in the number of bubbles with longitude with an increase of about a factor of 2 from 2{deg} to 10{deg}; this is probably the result of several factors, including decreasing diffuse background brightness, confusion, and opacity with longitude. Bubble eccentricities are typically between 0.6 and 0.8, and >50% show evidence for blowouts, which we suggest result from local density fluctuations of the ISM and/or anisotropic stellar winds and radiation fields.
- ID:
- ivo://CDS.VizieR/I/31
- Title:
- Bucharest KSZ Faint Stars, -11 to +11, 1950.0
- Short Name:
- I/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains the results of the differential observations of 3939 stars made with the Transit Circle of the Bucharest Observatory, from 1955 July 1 to 1962 June 16. The positions were observed simultaneously with the Catalog of the Southern Reference Star program. 105 stars were selected to be near extragalactic nebulae; the remaining 3852 stars were from the KSZ list. The positions are on the FK3R system for the equinox, 1950.0. Mean errors are 0.029s and 0.49" in right ascension and declination, respectively. The catalog contains for each star, in addition to the positions: the BD number, magnitude, spectral type, individual mean errors, epoch of the observations, number of observations in each coordinate, number of the star in the list of areas near extragalactic nebulae, and notes.
- 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.
- ID:
- ivo://CDS.VizieR/J/MNRAS/431/2111
- Title:
- BUDHIES I. redshifts and EW[OII]
- Short Name:
- J/MNRAS/431/2111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the optical spectroscopy for the Blind Ultra Deep HI Environmental Survey (BUDHIES). With the Westerbork Synthesis Radio Telescope, BUDHIES has detected HI in over 150 galaxies in and around two Abell clusters at z=~0.2. With the aim of characterizing the environments of the Hi-detected galaxies, we obtained multifibre spectroscopy with the William Herschel Telescope. In this paper, we describe the spectroscopic observations, report redshifts and EW[OII] measurements for ~600 galaxies, and perform an environmental analysis. In particular, we present cluster velocity dispersion measurements for five clusters and groups in the BUDHIES volume, as well as a detailed substructure analysis.
- ID:
- ivo://CDS.VizieR/J/MNRAS/440/1690
- Title:
- Bulge and disc colours of ETG in Coma
- Short Name:
- J/MNRAS/440/1690
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the internal structure of red-sequence galaxies in the Coma cluster across a wide range of luminosities (-17>M_g_>-22) and cluster-centric radii (0<r_cluster_<1.3r_200_). We present the 2D bulge-disc decomposition of galaxies in deep Canada-France-Hawaii Telescope u, g, i imaging using GALFIT. Rigorous filtering is applied to identify an analysis sample of 200 galaxies which are well described by an 'archetypal' S0 structure (central bulge + outer disc).
- 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.
- ID:
- ivo://CDS.VizieR/J/A+A/486/177
- Title:
- Bulge field stars from FLAMES-GIRAFFE spectra
- Short Name:
- J/A+A/486/177
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We determine the iron distribution function (IDF) for bulge field stars, in three different fields along the Galactic minor axis and at latitudes b=-4{deg}, b=-6{deg}, and b=-12{deg}. A fourth field including NGC 6553 is also included in the discussion. About 800 bulge field K giants were observed with the GIRAFFE spectrograph of FLAMES@VLT at spectral resolution R~20000. Several of them were observed again with UVES at R~45000 to insure the accuracy of the measurements. The LTE abundance analysis yielded stellar parameters and iron abundances that allowed us to construct an IDF for the bulge that, for the first time, is based on high-resolution spectroscopy for each individual star.
