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871. HI survey of the sky DE<+25{deg}
ID:
ivo://CDS.VizieR/VIII/75
Title:
HI survey of the sky DE<+25{deg}
Short Name:
VIII/75
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the final data release of the high sensitivity {lambda}21-cm neutral hydrogen survey of the sky south of {delta}<=-25{deg}. A total of 50980 positions lying on a galactic coordinate grid with points spaced by ({Delta}l, {Delta}b)=(0.5{deg}/cosb, 0.5{deg}) were observed with the 30m dish of the Instituto Argentino de Radioastronomica (IAR). The angular resolution of the survey is HPBW=0.5{deg} and the velocity coverage spans the interval -450km/s to +400km/s (LSR). The velocity resolution is 1.27km/s and the final rms noise of the entire database is 0.07K. The data are corrected for stray radiation and converted to brightness temperatures.
872. HLA Star Clusters ConeSearch
ID:
ivo://archive.stsci.edu/catalogs/HLASTARCLUSTERS
Title:
HLA Star Clusters ConeSearch
Short Name:
STARCLUSTERS CS
Date:
13 Feb 2020 17:47:36
Publisher:
Space Telescope Science Institute Archive
Description:
All MAST catalog holdings are available via a ConeSearch endpoint. A high-level science product was produced cataloging star clusters within the HLA: compact star cluster catalogs are presented for 20 nearby, star-forming galaxies using observations from the Advanced Catalog for Surveys (ACS) and source lists generated by the Hubble Legacy Archive. Results based on these cluster catalogs are published in the paper "The Luminosity Function of Star Clusters in 20 Star-Forming Galaxies Based on Hubble Legacy Archive Photometry" Whitmore, AJ 147:78. A typical cluster luminosity function can be approximated by a power-law, with an average value for the index of -2.37 and rms scatter = 0.18. The uniform database provided by these HLA catalogs results in a small scatter (0.5 magnitude) in the correlation between the magnitude of the brightest cluster (M_brightest) and Log of the number of clusters brighter than M_I = -9 (Log N). More information on the catalog is available at https://archive.stsci.edu/prepds/hlastarclusters/. All available missions are listed at http://archive.stsci.edu/vo/mast_services.html.
873. H_2_O + CH_3_OH maser survey of Orion protostars
ID:
ivo://CDS.VizieR/J/ApJS/209/25
Title:
H_2_O + CH_3_OH maser survey of Orion protostars
Short Name:
J/ApJS/209/25
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of a maser survey toward 99 protostars in the Orion molecular cloud complex are presented. The target sources are low-mass protostars identified from infrared observations. Single-dish observations were carried out in the water maser line at 22GHz and the methanol class I maser lines at 44, 95, and 133GHz. Most of the detected sources were mapped to determine the source positions. Five water maser sources were detected, and they are excited by HH 1-2 VLA 3, HH 1-2 VLA 1, L1641N MM1/3, NGC 2071 IRS 1/3, and an object in the OMC 3 region. The water masers showed significant variability in intensity and velocity with time scales of 1 month or shorter. Four methanol emission sources were detected, and those in the OMC 2 FIR 3/4 and L1641N MM1/3 regions are probably masers. The methanol emission from the other two sources in the NGC 2071 IRS 1-3 and V380 Ori NE regions are probably thermal. For the water masers, the number of detections per protostar in the survey region is about 2%, which suggests that the water masers of low-mass protostars are rarely detectable. The methanol class I maser of low-mass protostars is an even rarer phenomenon, with a detection rate much smaller than 1%.
874. Homogeneous sample of 34000 M7-M9.5 dwarfs
ID:
ivo://CDS.VizieR/J/A+A/623/A127
Title:
Homogeneous sample of 34000 M7-M9.5 dwarfs
Short Name:
J/A+A/623/A127
Date:
21 Oct 2021
Publisher:
CDS
Description:
The space density of late M dwarfs, sub-types M7 to M9.5, is not well determined. We have applied the photo-type method of Skrzypek et al. to iz photometry from SDSS and YJHK photometry from UKIDSS, over an effective area of 3070deg^2^, to produce a new, bright J(Vega)<17.5, homogeneous sample of 33665 M7 to M9.5 dwarfs. The typical S/N of each source summed over the 6 bands is >100. Classifications are provided to the nearest half spectral sub-type. Through comparison with the classifications in the BUD spectroscopic sample of Schmidt et al. (2010, Cat. J/AJ/139/1808), the typing is shown to be accurately calibrated to the BUD classifications, with a precision better than 0.5 sub-types rms, i.e. is as precise as good spectroscopic classification. Sources with large chisq>20 include several catalogued late-type subdwarfs. The new sample of late M dwarfs is highly complete, but there is a bias in the classification of rare peculiar blue or red objects. For example L subdwarfs are misclassified towards earlier types by approximately two spectral sub-types. We estimate that this bias affects only ~1% of sources. Therefore the sample is well suited for measuring the luminosity function, as well as investigating the softening towards the Galactic plane of the exponential variation of density with height.
875. Host galaxies of SNe Ia in SDSS-II SN survey
ID:
ivo://CDS.VizieR/J/ApJ/722/566
Title:
Host galaxies of SNe Ia in SDSS-II SN survey
Short Name:
J/ApJ/722/566
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of the host galaxy dependences of Type Ia Supernovae (SNe Ia) from the full three year sample of the SDSS-II Supernova Survey. We re-discover, to high significance, the strong correlation between host galaxy type and the width of the observed SN light curve, i.e., fainter, quickly declining SNe Ia favor passive host galaxies, while brighter, slowly declining Ia's favor star-forming galaxies. We also find evidence (at between 2{sigma} and 3{sigma}) that SNe Ia are ~0.1+/-0.04mag brighter in passive host galaxies than in star-forming hosts, after the SN Ia light curves have been standardized using the light-curve shape and color variations. This difference in brightness is present in both the SALT2 and MCLS2k2 light-curve fitting methodologies. We see evidence for differences in the SN Ia color relationship between passive and star-forming host galaxies, e.g., for the MLCS2k2 technique, we see that SNe Ia in passive hosts favor a dust law of R_V_=1.0+/-0.2, while SNe Ia in star-forming hosts require R_V_=1.8^+0.2^_-0.4_. The significance of these trends depends on the range of SN colors considered. We demonstrate that these effects can be parameterized using the stellar mass of the host galaxy (with a confidence of >4{sigma}) and including this extra parameter provides a better statistical fit to our data. Our results suggest that future cosmological analyses of SN Ia samples should include host galaxy information.
876. Host galaxies of SNIa from SNfactory
ID:
ivo://CDS.VizieR/J/ApJ/770/107
Title:
Host galaxies of SNIa from SNfactory
Short Name:
J/ApJ/770/107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photometric and spectroscopic observations of galaxies hosting Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory. Combining Galaxy Evolution Explorer (GALEX) UV data with optical and near-infrared photometry, we employ stellar population synthesis techniques to measure SN Ia host galaxy stellar masses, star formation rates (SFRs), and reddening due to dust. We reinforce the key role of GALEX UV data in deriving accurate estimates of galaxy SFRs and dust extinction. Optical spectra of SN Ia host galaxies are fitted simultaneously for their stellar continua and emission lines fluxes, from which we derive high-precision redshifts, gas-phase metallicities, and H{alpha}-based SFRs. With these data we show that SN Ia host galaxies present tight agreement with the fiducial galaxy mass-metallicity relation from Sloan Digital Sky Survey (SDSS) for stellar masses log(M_*_/M_{sun}_)>8.5 where the relation is well defined. The star formation activity of SN Ia host galaxies is consistent with a sample of comparable SDSS field galaxies, though this comparison is limited by systematic uncertainties in SFR measurements. Our analysis indicates that SN Ia host galaxies are, on average, typical representatives of normal field galaxies.
877. Hot degenerates in the MCT survey. III.
ID:
ivo://CDS.VizieR/J/AJ/162/188
Title:
Hot degenerates in the MCT survey. III.
Short Name:
J/AJ/162/188
Date:
21 Mar 2022 00:13:43
Publisher:
CDS
Description:
We present optical spectra of 144 white dwarfs detected in the Montreal-Cambridge-Tololo colorimetric survey, including 120 DA, 12 DB, 4 DO, 1 DQ, and 7 DC stars. We also perform a model atmosphere analysis of all objects in our sample using the so-called spectroscopic technique, or the photometric technique in the case of DC white dwarfs. The main objective of this paper is to contribute to the ongoing effort of confirming spectroscopically all white dwarf candidates in the Gaia survey, in particular in the southern hemisphere. All our spectra are made available in the Montreal White Dwarf Database.
878. Hot stars observed by XMM-Newton. II.
ID:
ivo://CDS.VizieR/J/A+A/619/A148
Title:
Hot stars observed by XMM-Newton. II.
Short Name:
J/A+A/619/A148
Date:
21 Oct 2021
Publisher:
CDS
Description:
We perform a survey of Oe and Be stars in the X-ray range. To this aim, we cross-correlated XMM-Newton and Chandra catalogs of X-ray sources with a list of Be stars, finding 84 matches in total. Of these, 51 objects had enough counts for a spectral analysis. This paper provides the derived X-ray properties (X-ray luminosities, and whenever possible, hardness ratios, plasma temperatures, and variability assessment) of this largest ever sample of Oe and Be stars. The targets display a wide range in luminosity and hardness. In particular, the significant presence of very bright and hard sources is atypical for X-ray surveys of OB stars. Several types of sources are identified. A subset of stars display the typical characteristics of O-stars, magnetic OB stars, or pre-main-sequence (PMS) objects: their Be nature does not seem to play an important role. However, another subset comprises gamma Cas analogs, which are responsible for the luminous and hard detections. Our sample contains seven known gamma Cas analogs, but we also identify eight new gamma Cas analogs and one gamma Cas candidate. This nearly doubles the sample of such stars.
879. Hot subdwarf stars from Gaia DR2 and LAMOST DR5. II.
ID:
ivo://CDS.VizieR/J/ApJ/881/135
Title:
Hot subdwarf stars from Gaia DR2 and LAMOST DR5. II.
Short Name:
J/ApJ/881/135
Date:
21 Oct 2021
Publisher:
CDS
Description:
Three hundred and eighty eight hot subdwarf stars have been identified by using the Hertzsprung-Russell (HR) diagram built from the second data release of the Gaia mission. By analyzing their observed Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) spectra, we characterized 186 sdB, 73 He-sdOB, 65 sdOB, 45 sdO, 12 He-sdO, and 7 He-sdB stars. The atmospheric parameters of these stars (e.g., Teff, logg, log(nHe/nH)) are obtained by fitting the hydrogen (H) and helium (He) line profiles with synthetic spectra calculated from non-local thermodynamic equilibrium model atmospheres. Among these stars, we have 135 new identified hot subdwarfs which have not been cataloged before. Although 253 stars appear in the catalog by Geier+ (2017, J/A+A/600/A50), only 91 of them have atmospheric parameters. Together with the 294 hot subdwarf stars found by Lei+ (Paper I, 2018, J/ApJ/868/70), we identified 682 hot subdwarf stars in total by using the Gaia HR-diagram and LAMOST spectra. These results demonstrate the efficiency of our method to combine large surveys to search for hot subdwarf stars. We found a distinct gap in our He-sdOB stars based on their He abundance, which is also presented in extreme horizontal branch (EHB) stars of the globular cluster {omega} Cen. The number fraction of the sample size for the two subgroups is very different between the two counterparts. However, the distinct gap between the H-sdB stars and He-sdOB stars in {omega} Cen is not visible in our sample. More interestingly, the He-sdB population with the highest He abundance in our sample is completely missing in {omega} Cen. The discrepancy between our field hot subdwarf stars and the EHB stars in {omega} Cen indicate different origins for the two counterparts.
880. Hot subdwarf stars in LAMOST DR1
ID:
ivo://CDS.VizieR/J/ApJ/818/202
Title:
Hot subdwarf stars in LAMOST DR1
Short Name:
J/ApJ/818/202
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 166 spectroscopically identified hot subdwarf stars from LAMOST DR1, 44 of which show the characteristics of cool companions in their optical spectra. Atmospheric parameters of 122 subdwarf stars with non-composite spectra were measured by fitting the profiles of hydrogen (H) and helium (He) lines with synthetic spectra from non-LTE model atmospheres. A unique property of our sample is that it covers a large range in apparent magnitude and galactic latitude, therefore it contains a mix of stars from different populations and galactic environments.

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