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15331. The BGPS. VII. Massive star-forming regions
ID:
ivo://CDS.VizieR/J/ApJ/741/110
Title:
The BGPS. VII. Massive star-forming regions
Short Name:
J/ApJ/741/110
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a Green Bank Telescope survey of NH_3_(1,1), (2,2), (3,3) lines toward 631 Bolocam Galactic Plane Survey (BGPS) sources at a range of Galactic longitudes in the inner Galaxy. We have detected the NH_3_(1,1) line toward 72% of our targets (456), demonstrating that the high column density features identified in the BGPS and other continuum surveys accurately predict the presence of dense gas. We have determined kinematic distances and resolved the distance ambiguity for all BGPS sources detected in NH_3_. The BGPS sources trace the locations of the Scutum and Sagittarius spiral arms, with the number of sources peaking between R_Gal_~4 and 5kpc. We measure the physical properties of each source and find that depending on the distance, BGPS sources are primarily clumps, with some cores and clouds. Forty-eight percent of our sample should be forming stars (including massive stars) with high efficiency, and 87% contain subregions that should be efficiently forming stars. Indeed, we find that 67% of the sample exhibit signs of star formation activity based on an association with a mid-infrared source.
15332. The BGPS. X. Dense molecular gas
ID:
ivo://CDS.VizieR/J/ApJS/209/2
Title:
The BGPS. X. Dense molecular gas
Short Name:
J/ApJS/209/2
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Bolocam Galactic Plane Survey (BGPS) is a 1.1 mm continuum survey of dense clumps of dust throughout the Galaxy covering 170deg^2^. We present spectroscopic observations using the Heinrich Hertz Submillimeter Telescope of the dense gas tracers, HCO^+^ and N_2_H^+^3-2, for all 6194 sources in the BGPS v1.0.1 catalog between 7.5{deg}<=l<=194{deg}. This is the largest targeted spectroscopic survey of dense molecular gas in the Milky Way to date. We find unique velocities for 3126 (50.5%) of the BGPS v1.0.1 sources observed. Strong N_2_H^+^ 3-2 emission (T_mb_>0.5K) without HCO^+^ 3-2 emission does not occur in this catalog. We characterize the properties of the dense molecular gas emission toward the entire sample. HCO^+^ is very sub-thermally populated and the 3-2 transitions are optically thick toward most BGPS clumps. The median observed line width is 3.3 km/s consistent with supersonic turbulence within BGPS clumps. We find strong correlations between dense molecular gas integrated intensities and 1.1 mm peak flux and the gas kinetic temperature derived from previously published NH_3_observations. These intensity correlations are driven by the sensitivity of the 3-2 transitions to excitation conditions rather than by variations in molecular column density or abundance. We identify a subset of 113 sources with stronger N_2_H^+^ than HCO^+^ integrated intensity, but we find no correlations between the N_2_H^+^/HCO^+^ ratio and 1.1 mm continuum flux density, gas kinetic temperature, or line width. Self-absorbed profiles are rare (1.3%).
15333. The 2BIGB gamma-ray blazars catalog
ID:
ivo://CDS.VizieR/J/MNRAS/493/2438
Title:
The 2BIGB gamma-ray blazars catalog
Short Name:
J/MNRAS/493/2438
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents the results of a {gamma}-ray likelihood analysis over all the extreme and high synchrotron peak blazars (EHSP and HSP) from the 3HSP catalogue. We investigate 2013 multifrequency positions under the eyes of Fermi Large Area Telescope, considering 11yr of observations in the energy range between 500MeV and 500GeV, which results in 1160 {gamma}-ray signatures detected down to the TS=9 threshold. The detections include 235 additional sources concerning the Fermi Large Area Telescope Fourth Source Catalog (4FGL), all confirmed via high-energy TS (Test Statistic) maps, and represent an improvement of ~25% for the number of EHSP and HSP currently described in {gamma}-rays. We build the {gamma}-ray spectral energy distribution (SED) for all the 1160 2BIGB sources, plot the corresponding {gamma}-ray logN-logS, and measure their total contribution to the extragalactic gamma-ray background, which reaches up to ~33% at 100GeV. Also, we show that the {gamma}-ray detectability improves according to the synchrotron peak flux as represented by the figure of merit parameter, and note that the search for TeV peaked blazars may benefit from considering HSP and EHSP as a whole, instead of EHSPs only. The 2BIGB acronym stands for 'Second Brazil-ICRANet Gamma-ray Blazars' catalogue.
15334. The black hole-bulge relationship
ID:
ivo://CDS.VizieR/J/AJ/135/928
Title:
The black hole-bulge relationship
Short Name:
J/AJ/135/928
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have measured the stellar velocity dispersions ({sigma}_*_) and estimated the central black hole (BH) masses for over 900 broad-line active galactic nuclei (AGNs) observed with the Sloan Digital Sky Survey. The sample includes objects which have redshifts up to z=0.452, high-quality spectra, and host galaxy spectra dominated by an early-type (bulge) component. The AGN and host galaxy spectral components were decomposed using an eigenspectrum technique. The BH masses (M_BH_) were estimated from the AGN broad-line widths, and the velocity dispersions were measured from the stellar absorption spectra of the host galaxies. The range of black hole masses covered by the sample is approximately 10^6^<M_BH_<10^9^M_{sun}_. We find no significant evolution in the M_BH_-{sigma}_*_ relation with redshift, up to z~0.4, after controlling for possible dependences on other variables. Interested readers can contact the authors to obtain the eigenspectrum decomposition coefficients of our objects.
15335. The Blanco Cosmology Survey (BCS)
ID:
ivo://CDS.VizieR/J/ApJ/757/83
Title:
The Blanco Cosmology Survey (BCS)
Short Name:
J/ApJ/757/83
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Blanco Cosmology Survey (BCS) is a 60 night imaging survey of ~80deg^2^ of the southern sky located in two fields: (5hr,-55{deg}) and (23hr,-55{deg}). The survey was carried out between 2005 and 2008 in griz bands with the Mosaic2 imager on the Blanco 4m telescope. The primary aim of the BCS survey is to provide the data required to optically confirm and measure photometric redshifts for Sunyaev-Zel'dovich effect selected galaxy clusters from the South Pole Telescope and the Atacama Cosmology Telescope. We process and calibrate the BCS data, carrying out point-spread function-corrected model-fitting photometry for all detected objects. The median 10{sigma} galaxy (point-source) depths over the survey in griz are approximately 23.3 (23.9), 23.4 (24.0), 23.0 (23.6), and 21.3 (22.1), respectively. The astrometric accuracy relative to the USNO-B survey is ~45mas. We calibrate our absolute photometry using the stellar locus in grizJ bands, and thus our absolute photometric scale derives from the Two Micron All Sky Survey, which has ~2% accuracy. The scatter of stars about the stellar locus indicates a systematic floor in the relative stellar photometric scatter in griz that is ~1.9%, ~2.2%, ~2.7%, and ~2.7%, respectively. A simple cut in the AstrOmatic star-galaxy classifier spread_ model produces a star sample with good spatial uniformity. We use the resulting photometric catalogs to calibrate photometric redshifts for the survey and demonstrate scatter {delta}z/(1+z)=0.054 with an outlier fraction {eta}<5% to z~1. We highlight some selected science results to date and provide a full description of the released data products.
15336. The blueshift of the C IV broad emission line in QSOs
ID:
ivo://CDS.VizieR/J/AJ/157/148
Title:
The blueshift of the C IV broad emission line in QSOs
Short Name:
J/AJ/157/148
Date:
21 Oct 2021
Publisher:
CDS
Description:
For the sample from Ge et al. (2016MNRAS.462..966G) of 87 low-z Palomar-Green quasi-stellar objects (QSOs) and 130 high-z QSOs (0<z<5) with H{beta}-based single-epoch supermassive black hole masses, we perform a uniform decomposition of the C IV {lambda}1549 broad-line profile. Based on the rest frame defined by the [O III] {lambda}5007 narrow emission line, a medium-strong positive correlation is found between the C IV blueshift and the luminosity at 5100 {AA} or the Eddington ratio L_Bol_/L_Edd_. A medium-strong negative relationship is found between the C IV blueshift and C IV equivalent width. These results support the postulation where the radiation pressure may be the driver of C IV blueshift. There is a medium-strong correlation between the mass ratio of C IV-based to H{beta}-based M_BH_ and the C IV blueshift, which indicates that the bias for C IV-based M_BH_ is affected by the C IV profile.
15337. The Bok globule CB 26
ID:
ivo://CDS.VizieR/J/A+A/646/A18
Title:
The Bok globule CB 26
Short Name:
J/A+A/646/A18
Date:
23 Mar 2022 16:32:20
Publisher:
CDS
Description:
Planetary cores are thought to form in proto-planetary disks via the growth of dusty solid material. However, it is unclear how early this process begins. We study the physical structure and grain growth in the edge-on disk that surrounds the ~1Myr old low-mass (~0.55M_{sun}_) protostar embedded in the Bok Globule CB26 to examine how much grain growth has already occurred in the protostellar phase. We combine the SED between 0.9um and 6.4cm with high angular resolution continuum maps at 1.3, 2.9, and 8.1mm, and use the radiative transfer code RADMC-3D to conduct a detailed modelling of the dust emission from the disk and envelope of CB 26. We infer inner and outer disk radii of around 16au and 172+/-22au, respectively. The total gas mass in the disk is ~0.076M_{sun}_, which amounts to ~14% of the mass of the central star. The inner disk contains a compact free-free emission region, which could be related to either a jet or a photoevaporation region. The thermal dust emission from the outer disk is optically thin at mm wavelengths, while the emission from the inner disk midplane is moderately optically thick. Our best-fit radiative transfer models indicate that the dust grains in the disk have already grown to pebbles with diameters of the order of 10cm in size. Residual 8.1mm emission suggests the presence of even larger particles in the inner disk. For the optically thin mm dust emission from the outer disk, we derive a mean opacity slope of {beta}_mm_~=0.7+/-0.4, which is consistent with the presence of large dust grains. The presence of cm-sized bodies in the CB 26 disk indicates that solids grow rapidly already during the first million years in a protostellar disk. It is thus possible that Class II disks are already seeded with large particles and may contain even planetesimals.
15338. The Bolocam Galactic Plane Survey (BGPS)
ID:
ivo://CDS.VizieR/J/ApJ/721/137
Title:
The Bolocam Galactic Plane Survey (BGPS)
Short Name:
J/ApJ/721/137
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Bolocam Galactic Plane Survey (BGPS) data for a 6deg^2^ region of the Galactic plane containing the Galactic center are analyzed and compared to infrared and radio continuum data. The BGPS 1.1mm emission consists of clumps interconnected by a network of fainter filaments surrounding cavities, a few of which are filled with diffuse near-IR emission indicating the presence of warm dust or with radio continuum characteristic of HII regions or supernova remnants. New 350um images of the environments of the two brightest regions, Sgr A and B, are presented. Sgr B2 is the brightest millimeter-emitting clump in the Central Molecular Zone (CMZ) and may be forming the closest analog to a super star cluster in the Galaxy. The CMZ contains the highest concentration of millimeter- and submillimeter-emitting dense clumps in the Galaxy. Most 1.1mm features at positive longitudes are seen in silhouette against the 3.6-24um background observed by the Spitzer Space Telescope. However, only a few clumps at negative longitudes are seen in absorption, confirming the hypothesis that positive longitude clumps in the CMZ tend to be on the near side of the Galactic center, consistent with the suspected orientation of the central bar in our Galaxy. The Bolocat catalog of 1.1mm clumps contains 1428 entries in the Galactic center between l=358.5{deg} and l=4.5{deg} of which about 80% are likely to be within about 500pc of the center.
15339. The Bolocam Galactic Plane Survey (BGPS). V.
ID:
ivo://CDS.VizieR/J/ApJS/195/14
Title:
The Bolocam Galactic Plane Survey (BGPS). V.
Short Name:
J/ApJS/195/14
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of observations of 1882 sources in the Bolocam Galactic Plane Survey (BGPS) at 1.1mm with the 10m Henrich Hertz Telescope simultaneously in HCO^+^J=3-2 and N_2_H^+^J=3-2. We detect 77% of these sources in HCO^+^ and 51% in N_2_H^+^ at greater than 3{sigma}. We find a strong correlation between the integrated intensity of both dense gas tracers and the 1.1mm dust emission of BGPS sources. We determine kinematic distances for 529 sources (440 in the first quadrant breaking the distance ambiguity and 89 in the second quadrant). We derive the size, mass, and average density for this subset of clumps. The median size of BGPS clumps is 0.75pc with a median mass of 330M_{sun}_ (assuming T_Dust_=20K). BGPS clumps represent a wide range of objects (from dense cores to more diffuse clumps) and are typically characterized by larger sizes and lower densities than previously published surveys of high-mass star-forming regions.
15340. The Bolocam Galactic Plane Survey. II.
ID:
ivo://CDS.VizieR/J/ApJS/188/123
Title:
The Bolocam Galactic Plane Survey. II.
Short Name:
J/ApJS/188/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 8358 sources extracted from images produced by the Bolocam Galactic Plane Survey (BGPS). The BGPS is a survey of the millimeter dust continuum emission from the northern Galactic plane. The catalog sources are extracted using a custom algorithm, Bolocat, which was designed specifically to identify and characterize objects in the large-area maps generated from the Bolocam instrument. The catalog products are designed to facilitate follow-up observations of these relatively unstudied objects. The catalog is 98% complete from 0.4Jy to 60Jy over all object sizes for which the survey is sensitive (<3.5'). We find that the sources extracted can best be described as molecular clumps-large dense regions in molecular clouds linked to cluster formation. We find that the flux density distribution of sources follows a power law with dN/dS{prop.to}S^-2.4+/-0.1^ and that the mean Galactic latitude for sources is significantly below the midplane: <b>=(-0.095+/-0.001{deg}).

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