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17311. Water masers in M31. II. Multiwavelength data
ID:
ivo://CDS.VizieR/J/ApJ/826/136
Title:
Water masers in M31. II. Multiwavelength data
Short Name:
J/ApJ/826/136
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a comparative multiwavelength analysis of water-maser-emitting regions and non-maser-emitting luminous 24{mu}m star-forming regions in the Andromeda Galaxy (M31) to identify the sites most likely to produce luminous water masers useful for astrometry and proper motion studies. Included in the analysis are Spitzer 24{mu}m photometry, Herschel 70 and 160{mu}m photometry, H{alpha} emission, dust temperature, and star-formation rate. We find significant differences between the maser-emitting and non-maser-emitting regions: water-maser-emitting regions tend to be more infrared-luminous and show higher star-formation rates. The five water masers in M31 are consistent with being analogs of water masers in Galactic star-forming regions and represent the high-luminosity tail of a larger (and as yet undetected) population. Most regions likely to produce water masers bright enough for proper motion measurements using current facilities have already been surveyed, but we suggest three ways to detect additional water masers in M31: (1) reobserve the most luminous mid- or far-infrared sources with higher sensitivity than was used in the Green Bank Telescope survey; (2) observe early-stage star-forming regions selected by millimeter continuum that have not already been selected by their 24{mu}m emission, and (3) reobserve the most luminous mid- or far-infrared sources and rely on maser variability for new detections.
17312. Water masers in M31. I. Recombination lines
ID:
ivo://CDS.VizieR/J/ApJ/826/24
Title:
Water masers in M31. I. Recombination lines
Short Name:
J/ApJ/826/24
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results of a Green Bank Telescope survey for water masers, ammonia (1,1) and (2,2), and the H66{alpha} recombination line toward 506 luminous compact 24{mu}m emitting regions in the Andromeda Galaxy (M31). We include the 206 sources observed in the Darling water maser survey for completeness. The survey was sensitive enough to detect any maser useful for ~10{mu}as/yr astrometry. No new water masers, ammonia lines, or H66{alpha} recombination lines were detected individually or in spectral stacks reaching rms noise levels of ~3mJy and ~0.2mJy, respectively, in 3.1-3.3km/s channels. The lack of detections in individual spectra and in the spectral stacks is consistent with Galactic extrapolations. Contrary to previous assertions, there do not seem to be any additional bright water masers to be found in M31. The strong variability of water masers may enable new maser detections in the future, but variability may also limit the astrometric utility of known (or future) masers because flaring masers must also fade.
17313. Water masers in Orion
ID:
ivo://CDS.VizieR/J/ApJ/493/940
Title:
Water masers in Orion
Short Name:
J/ApJ/493/940
Date:
21 Oct 2021
Publisher:
CDS
Description:
Measurements of the 6_16_ -> 5_23_ line of H_2_O at 1.3cm in the Orion region of star formation are reported. With a spatial resolution of ~0.1", H_2_O maser emission was detected in two regions: Orion BN/KL and Orion S. The well-known masers in the BN/KL region are distributed in a 30"x30" area. The "shell" masers, within the BN/KL region, are distributed in a 2" by 0.5" strip centered on radio source I and are offset from IRc2.
17314. Water maser survey
ID:
ivo://CDS.VizieR/J/AJ/132/1322
Title:
Water maser survey
Short Name:
J/AJ/132/1322
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on the most sensitive water maser survey toward Bok globules to date, performed using NASA's 70m antenna at Robledo de Chavela (Spain). We observed 207 positions within the Clemens and Barvainis catalog with a higher probability of harboring a young star, using as selection criteria the presence of radio continuum emission (from submillimeter to centimeter wavelengths), geometric centers of molecular outflows, peaks in maps of high-density gas tracers (NH3 or CS), and IRAS point sources. We have obtained seven maser detections, six of which (in CB 34, CB 54, CB 65, CB 101, CB 199, and CB 232) are reported for the first time here. Most of the water masers we detected are likely to be associated with young stellar objects (YSOs), except for CB 101 (probably an evolved object) and CB 65 (uncertain nature). The water maser in CB 199 shows a relatively high shift (30km/s) of its velocity centroid with respect to the cloud velocity, which is unusual for low-mass YSOs. We speculate that high-velocity masers in this kind of object could be related to episodes of energetic mass loss in close binaries. Alternatively, the maser in CB 199 could be pumped by a protoplanetary or a young planetary nebula. CB 232 is the smallest Bok globule (0.6pc) known to be associated with water maser emission, although it would be superseded by the cases of CB 65 (0.3pc) and CB 199 (0.5pc) if their association with YSOs is confirmed. All our selection criteria have statistically compatible detection rates, except for IRAS sources, which tend to be somewhat worse predictors for the presence of maser emission.
17315. Water maser survey of late-type stars
ID:
ivo://CDS.VizieR/J/PASJ/53/517
Title:
Water maser survey of late-type stars
Short Name:
J/PASJ/53/517
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents new results of a water maser survey of late-type stellar objects at 22.235GHz with the Kashima 34-m radio telescope. We have detected 179 out of 643 observed sources, including 32 new detections. The sources were selected in terms of the IRAS flux density and colors of late-type stars, involving optically observable Mira/semi-regular variables, IRC objects, OH/IR sources and proto-planetary nebulae. We found the highest H_2_O detection rate for the type of stars with a thin dust envelope (Mira/semi-regular variables) among other types of sources. This is attributed to the smaller distances to such stars in the sample. The velocity spread of the H_2_O maser profile has an increasing tendency with the IRAS color, though it becomes more difficult to access this color dependence beyond an edge of the transition of the (oxygen-rich) Asymptotic Giant Branch stars to protoplanetary nebulae in the two-color diagram.
17316. Water maser survey of methanol maser sources
ID:
ivo://CDS.VizieR/J/A+A/434/613
Title:
Water maser survey of methanol maser sources
Short Name:
J/A+A/434/613
Date:
21 Oct 2021
Publisher:
CDS
Description:
High sensitivity observations of the 22GHz water maser emission have been carried out with the Effelsberg 100m radio telescope. The observed sample was 79 candidate high-mass protostellar objects from a flux-limited sample of 6.7GHz methanol sources (Szymczak et al., 2002A&A...392..277S). Water maser emission was found in 41 sources of which 28 were not previously catalogued.
17317. Wavelength Dependence of Galactic UV Extinction
ID:
ivo://CDS.VizieR/III/130
Title:
Wavelength Dependence of Galactic UV Extinction
Short Name:
III/130
Date:
21 Oct 2021
Publisher:
CDS
Description:
A collection of data for 115 extinction curves derived from low-dispersion IUE spectra are presented with normalization to E(B-V)=1. The electronic Atlas of Extinctions contains the list of the stars used, their association membership, and the normalized extinctions for 88 wavelength values between 1260 and 3000 Angstroems.
17318. WBL Individual Galaxies Data Catalog (White et al. 1999)
ID:
ivo://nasa.heasarc/wblgalaxy
Title:
WBL Individual Galaxies Data Catalog (White et al. 1999)
Short Name:
WBL
Date:
14 Feb 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Catalog of Nearby Poor Clusters of Galaxies of White et al. (1999), also known as the WBL Catalog, is a catalog of 732 optically selected, nearby poor clusters of galaxies covering the entire sky north of -3 degrees declination. The poor clusters, called WBL clusters, were identified as concentrations of three or more galaxies with photographic magnitudes brighter than 15.7, possessing a galaxy surface overdensity of 10^(4/3). These criteria are consistent with those used in the identification of the original Yerkes poor clusters, and this new catalog substantially increases the sample size of such objects. These poor clusters cover the entire range of galaxy associations up to and including Abell clusters, systematically including poor and rich galaxy systems spanning over 3 orders of magnitude in the cluster mass function. As a result, this new catalog contains a greater diversity of richness and structures than other group catalogs, such as the Hickson and Yerkes catalogs. This table contains the entries for the individual galaxies in the poor clusters which ere given in Table 3 of the published catalog, and includes redshifts for the individual galaxies and cross-references to other galaxy catalogs. The WBL table (q.v.) contains the entries for the clusters themselves (given in Table 2 of the published catalog). The WBLGALAXY table was created by the HEASARC in July 2002 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/118/2014">CDS Catalog J/AJ/118/2014</a> (the file table3.dat). This is a service provided by NASA HEASARC .
17319. WBL Poor Galaxy Clusters Catalog (White et al. 1999)
ID:
ivo://nasa.heasarc/wbl
Title:
WBL Poor Galaxy Clusters Catalog (White et al. 1999)
Short Name:
WBL
Date:
14 Feb 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Catalog of Nearby Poor Clusters of Galaxies of White et al. (1999), also known as the WBL Catalog, is a catalog of 732 optically selected, nearby poor clusters of galaxies covering the entire sky north of -3 degrees declination. The poor clusters, called WBL clusters, were identified as concentrations of three or more galaxies with photographic magnitudes brighter than 15.7, possessing a galaxy surface overdensity of 10^(4/3). These criteria are consistent with those used in the identification of the original Yerkes poor clusters, and this new catalog substantially increases the sample size of such objects. These poor clusters cover the entire range of galaxy associations up to and including Abell clusters, systematically including poor and rich galaxy systems spanning over 3 orders of magnitude in the cluster mass function. As a result, this new catalog contains a greater diversity of richness and structures than other group catalogs, such as the Hickson and Yerkes catalogs. This table contains the entries for the clusters (given in Table 2 of the published catalog) and includes redshift data (where available) and cross-references to other group and cluster catalogs. The WBLGALAXY table (q.v.) contains the entries for the individual galaxies in the clusters which ere given in Table 3 of the published catalog. The WBL table was created by the HEASARC in July 2002 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/118/2014">CDS Catalog J/AJ/118/2014</a> (the file table2.dat). This is a service provided by NASA HEASARC .
17320. W49B with H.E.S.S. and Fermi-LAT
ID:
ivo://CDS.VizieR/J/A+A/612/A5
Title:
W49B with H.E.S.S. and Fermi-LAT
Short Name:
J/A+A/612/A5
Date:
21 Oct 2021
Publisher:
CDS
Description:
The supernova remnant (SNR) W49B originated from a core-collapse supernova that occurred between one and four thousand years ago, and subsequently evolved into a mixed-morphology remnant, which is interacting with molecular clouds (MC). Gamma-ray observations of SNR-MC associations are a powerful tool to constrain the origin of Galactic cosmic rays, as they can probe the acceleration of hadrons through their interaction with the surrounding medium and subsequent emission of non-thermal photons. We report the detection of a gamma-ray source coincident with W49B at very high energies (VHE; E>100GeV) with the H.E.S.S. Cherenkov telescopes together with a study of the source with five years of Fermi-LAT high-energy gamma-ray (0.06-300GeV) data. The smoothly connected, combined source spectrum, measured from 60MeV to multi-TeV energies, shows two significant spectral breaks at 304+/-20MeV and 8.4_-2.5_^+2.2^GeV; the latter is constrained by the joint fit from the two instruments. The detected spectral features are similar to those observed in several other SNR-MC associations and are found to be indicative of gamma-ray emission produced through neutral-pion decay.

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