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211. Beta Cephei stars in the ASAS-3 data. I.
ID:
ivo://CDS.VizieR/J/A+A/477/907
Title:
Beta Cephei stars in the ASAS-3 data. I.
Short Name:
J/A+A/477/907
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyse V-filter photometry of 41 known Beta Cephei-type stars. The ASAS-3 photometry is combined with the archival data, if available, to determine long-term stability of periods and amplitudes of excited modes. We detected amplitude changes in three Beta Cephei stars, BW Cru, V836 Cen, and V348 Nor. Period changes were found in KK Vel and V836 Cen. Our analysis shows that intrinsic period changes are more common among multiperiodic stars, apparently because they are caused by some kind of mode interaction. In addition, we found new modes for seven stars, and for ten others we provide new solutions or remove ambiguities in the detected frequencies. One candidate hybrid Beta Cephei/SPB star, HD 133823, is discovered.
212. Beta Cephei stars in the ASAS-3 data. II.
ID:
ivo://CDS.VizieR/J/A+A/477/917
Title:
Beta Cephei stars in the ASAS-3 data. II.
Short Name:
J/A+A/477/917
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analysed ASAS-3 photometry of bright early-type stars with the goal of finding new Beta Cephei stars. We were particularly interested in Beta Cephei stars that would be good for seismic analysis, i.e., stars that (i) have a large number of excited modes, (ii) show rotationally split modes, (iii) are components of eclipsing binary systems, (iv) have low-frequency modes, that is, are hybrid Beta Cephei/SPB stars. Our study was made with a homogeneous sample of over 4100 stars having MK spectral type B5 or earlier. For these stars, the ASAS-3 photometry was analysed by means of a Fourier periodogram. We have discovered 103 Beta Cephei stars, nearly doubling the number of previously known stars of this type. Among these stars, four are components of eclipsing binaries, seven have modes equidistant or nearly equidistant in frequency. In addition, we found five Beta Cephei stars that show low-frequency periodic variations, very likely due to pulsations. We therefore regard them as candidate hybrid Beta Cephei/SPB pulsators. All these stars are potentially very useful for seismic modeling. Moreover, we found Beta Cephei-type pulsations in three late O-type stars and fast period changes in one, HD 168050.
213. BGDS Mean Photometry Cone Search
ID:
ivo://org.gavo.dc/bgds/l/meanphot
Title:
BGDS Mean Photometry Cone Search
Short Name:
BGDS mean phot
Date:
27 Dec 2024 08:31:01
Publisher:
The GAVO DC team
Description:
Extracted sources from the Bochum Galactic Disk Survey. We provide mean photometry in U, B, V, z, r, and i bands. Note that sources in different bands are not matched. Also, sources sitting in the regions imaged in multiple fields have not been matched even within one band. In i and r, BGDS light curves are available. See related services for details.
214. BGPS. IX. Data release 2.
ID:
ivo://CDS.VizieR/J/ApJS/208/14
Title:
BGPS. IX. Data release 2.
Short Name:
J/ApJS/208/14
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a re-reduction and expansion of the Bolocam Galactic Plane Survey (BGPS), first presented by Aguirre+ (2011ApJS..192....4A) and Rosolowsky+ (2011, J/ApJS/188/123). The BGPS is a 1.1mm survey of dust emission in the Northern galactic plane, covering longitudes -10{deg}<{ell}<90{deg} and latitudes |b|<0.5{deg} with a typical 1{sigma} rms sensitivity of 30-100mJy in a ~33" beam. Version 2 of the survey includes an additional ~20deg^2^ of coverage in the third and fourth quadrants and ~2deg^2^ in the first quadrant. The new data release has improved angular recovery, with complete recovery out to ~80" and partial recovery to ~300", and reduced negative bowls around bright sources resulting from the atmospheric subtraction process. We resolve the factor of 1.5 flux calibration offset between the v1.0 data release and other data sets and determine that there is no offset between v2.0 and other data sets. The v2.0 pointing accuracy is tested against other surveys and is demonstrated to be accurate and an improvement over v1.0. We present simulations and tests of the pipeline and its properties, including measurements of the pipeline's angular transfer function. The Bolocat cataloging tool was used to extract a new catalog, which includes 8594 sources, with 591 in the expanded regions. We have demonstrated that the Bolocat 40" and 80" apertures are accurate even in the presence of strong extended background emission. The number of sources is lower than in v1.0, but the amount of flux and area included in identified sources is larger.
215. BGPS. VIII. MIR kinematic distances
ID:
ivo://CDS.VizieR/J/ApJ/770/39
Title:
BGPS. VIII. MIR kinematic distances
Short Name:
J/ApJ/770/39
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new distance estimation method for dust-continuum-identified molecular cloud clumps. Recent (sub-)millimeter Galactic plane surveys have cataloged tens of thousands of these objects, plausible precursors to stellar clusters, but detailed study of their physical properties requires robust distance determinations. We derive Bayesian distance probability density functions (DPDFs) for 770 objects from the Bolocam Galactic Plane Survey in the Galactic longitude range 7.5{deg}<=l<=65{deg}. The DPDF formalism is based on kinematic distances, and uses any number of external data sets to place prior distance probabilities to resolve the kinematic distance ambiguity (KDA) for objects in the inner Galaxy. We present here priors related to the mid-infrared absorption of dust in dense molecular regions and the distribution of molecular gas in the Galactic disk. By assuming a numerical model of Galactic mid-infrared emission and simple radiative transfer, we match the morphology of (sub-)millimeter thermal dust emission with mid-infrared absorption to compute a prior DPDF for distance discrimination. Selecting objects first from (sub-)millimeter source catalogs avoids a bias towards the darkest infrared dark clouds (IRDCs) and extends the range of heliocentric distance probed by mid-infrared extinction and includes lower-contrast sources. We derive well-constrained KDA resolutions for 618 molecular cloud clumps, with approximately 15% placed at or beyond the tangent distance. Objects with mid-infrared contrast sufficient to be cataloged as IRDCs are generally placed at the near kinematic distance. Distance comparisons with Galactic Ring Survey KDA resolutions yield a 92% agreement. A face-on view of the Milky Way using resolved distances reveals sections of the Sagittarius and Scutum-Centaurus Arms. This KDA-resolution method for large catalogs of sources through the combination of (sub-)millimeter and mid-infrared observations of molecular cloud clumps is generally applicable to other dust-continuum Galactic plane surveys.
216. BGPS. XI. SHARC-II 350um observations
ID:
ivo://CDS.VizieR/J/ApJS/218/1
Title:
BGPS. XI. SHARC-II 350um observations
Short Name:
J/ApJS/218/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 107 maps of continuum emission at 350{mu}m from Galactic molecular clumps. Observed sources were mainly selected from the Bolocam Galactic Plane Survey (BGPS) catalog, with three additional maps covering star-forming regions in the outer Galaxy. The higher resolution of the SHARC-II images (8.5" beam) compared with the 1.1mm images from BGPS (33" beam) allowed us to identify a large population of smaller substructures within the clumps. A catalog is presented for the 1386 sources extracted from the 350{mu}m maps. The color temperature distribution of clumps based on the two wavelengths has a median of 13.3K and mean of 16.3+/-0.4K, assuming an opacity law index of 1.7. For the structures with good determination of color temperatures, the mean ratio of gas temperature, determined from NH_3_ observations, to dust color temperature is 0.88 and the median ratio is 0.76. About half the clumps have more than 2 substructures and 22 clumps have more than 10. The fraction of the mass in dense substructures seen at 350{mu}m compared to the mass of their parental clump is ~0.19, and the surface densities of these substructures are, on average, 2.2 times those seen in the clumps identified at 1.1mm. For a well-characterized sample, 88 structures (31%) exceed a surface density of 0.2g/cm2, and 18 (6%) exceed 1.0g/cm2, thresholds for massive star formation suggested by theorists.
217. BGPS. XIV. Molecular cloud clumps GBT obs.
ID:
ivo://CDS.VizieR/J/ApJ/822/59
Title:
BGPS. XIV. Molecular cloud clumps GBT obs.
Short Name:
J/ApJ/822/59
Date:
21 Oct 2021
Publisher:
CDS
Description:
We sort 4683 molecular clouds between 10{deg}<l<65{deg} from the Bolocam Galactic Plane Survey based on observational diagnostics of star formation activity: compact 70{mu}m sources, mid-IR color-selected YSOs, H_2_O and CH_3_OH masers, and UCHII regions. We also present a combined NH_3_-derived gas kinetic temperature and H_2_O maser catalog for 1788 clumps from our own GBT 100m observations and from the literature. We identify a subsample of 2223 (47.5%) starless clump candidates (SCCs), the largest and most robust sample identified from a blind survey to date. Distributions of flux density, flux concentration, solid angle, kinetic temperature, column density, radius, and mass show strong (>1dex) progressions when sorted by star formation indicator. The median SCC is marginally subvirial ({alpha}~0.7) with >75% of clumps with known distance being gravitationally bound ({alpha}<2). These samples show a statistically significant increase in the median clump mass of {Delta}M~170-370M_{sun}_ from the starless candidates to clumps associated with protostars. This trend could be due to (i) mass growth of the clumps at dM/dt~200-440M_{sun}_/Myr for an average freefall 0.8Myr timescale, (ii) a systematic factor of two increase in dust opacity from starless to protostellar phases, and/or (iii) a variation in the ratio of starless to protostellar clump lifetime that scales as ~M^-0.4^. By comparing to the observed number of CH_3_OH maser containing clumps, we estimate the phase lifetime of massive (M>10^3^M_{sun}_) starless clumps to be 0.37+/-0.08Myr (M/10^3^M_{sun}_)^-1^; the majority (M<450M_{sun}_) have phase lifetimes longer than their average freefall time.
218. BH masses and bulge+disk UV-3.6um color relations
ID:
ivo://CDS.VizieR/J/ApJ/898/83
Title:
BH masses and bulge+disk UV-3.6um color relations
Short Name:
J/ApJ/898/83
Date:
21 Mar 2022 08:47:28
Publisher:
CDS
Description:
The tight correlations between supermassive black hole (SMBH) mass (MBH) and the properties of the host galaxy have useful implications for our understanding of the growth of SMBHs and of the evolution of galaxies. Here, we present newly observed correlations between MBH and the host galaxy total UV-[3.6] color (C_UV,tot_, Pearson's r=0.6-0.7) for a sample of 67 galaxies (20 early-type galaxies and 47 late-type galaxies) with directly measured MBH in the Galaxy Evolution Explorer/S4G survey. The colors are carefully measured in a homogeneous manner using the far-UV, near-UV, and 3.6{mu}m magnitudes of the galaxies and their multicomponent structural decompositions in the literature. We find that more massive SMBHs are hosted by (early- and late-type) galaxies with redder colors, but the M_BH_-C_UV,tot_ relations for the two morphological types have slopes that differ at ~2{sigma} level. Early-type galaxies define a red sequence in the M_BH_-C_UV,tot_ diagrams, while late-type galaxies trace a blue sequence. Within the assumption that the specific star formation rate of a galaxy (sSFR) is well traced by L_UV_/L_3.6_, it follows that the SMBH masses for late-type galaxies exhibit a steeper dependence on sSFR than those for early-type galaxies. The M_BH_-C_UV,tot_ and M_BH_-L_3.6,tot_ relations for the sample galaxies reveal a comparable level of vertical scatter in the log MBH direction, approximately 5%-27% more than the vertical scatter of the M_BH_-{sigma} relation. Our M_BH_-C_UV,tot_ relations suggest different channels of SMBH growth for early- and late-type galaxies, consistent with their distinct formation and evolution scenarios. These new relations offer the prospect of estimating SMBH masses reliably using the galaxy color alone. Furthermore, we show that they are capable of estimating intermediate black hole masses in low-mass early- and late-type galaxies.
219. BIMA CMB anisotropy survey
ID:
ivo://CDS.VizieR/J/ApJ/647/13
Title:
BIMA CMB anisotropy survey
Short Name:
J/ApJ/647/13
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the final results of our study of the cosmic microwave background (CMB) with the BIMA array. Over 1000hr of observation were dedicated to this project exploring CMB anisotropy, on scales between 1' and 2' in eighteen 6.6' FWHM fields. In the analysis of the CMB power spectrum, the visibility data are divided into two bins, corresponding to different angular scales.
220. Bisei Space Guard Center images
ID:
ivo://jvo/isas/darts/bsgc
Title:
Bisei Space Guard Center images
Short Name:
BSGC_IMAGE
Date:
05 Feb 2025 04:12:46
Publisher:
JVO
Description:
Bisei Space Guard Center (BSGC) is an optical telescope facility in Japan, operated by JAXA. It tracks near-Earth asteroids and space debris. DARTS provides data observed by a 25 cm telescope from 2000 to 2002 and data observed by a 1 m telescope from 2007 to 2017.

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