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2351. SiO maser emission toward 10 late-type stars
ID:
ivo://CDS.VizieR/J/ApJS/165/360
Title:
SiO maser emission toward 10 late-type stars
Short Name:
J/ApJS/165/360
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of simultaneous time monitoring observations of SiO J=2-1 and J=3-2 maser emission for 10 late-type stars (8 Mira variables, 1 OH/IR star, and 1 supergiant) with the 14m radio telescope at Taeduk Radio Astronomy Observatory from 1999 January to 2001 February. The SiO v=1, J=2-1 and J=3-2 maser emission was detected at almost all observational epochs. The SiO v=2, J=2-1 maser was detected from 4 late-type stars (VY CMa, R Cas, Cyg, R Leo) and the v=2, J=3-2 maser was detected from 7 stars (R Aqr, TX Cam, R Cas, Cyg, W Hya, R Leo, IK Tau). The v=3, J=2-1 and masers were also detected from Cyg and TX Cam, respectively. Based on these observational data, line profile and peak velocity variations with respect to stellar velocity, antenna temperatures, and their ratio variations as a function of optical phase of central star were investigated. Description:
2352. Six fossil central galaxies reduced spectra
ID:
ivo://CDS.VizieR/J/A+A/553/A99
Title:
Six fossil central galaxies reduced spectra
Short Name:
J/A+A/553/A99
Date:
21 Oct 2021
Publisher:
CDS
Description:
Fossil galaxy groups are speculated to be old and highly evolved systems of galaxies that formed early in the universe and had enough time to deplete their L* galaxies through successive mergers of member galaxies, building up one massive central elliptical, but retaining the group X-ray halo. Considering that fossils are the remnants of mergers in ordinary groups, the merger history of the progenitor group is expected to be imprinted in the fossil central galaxy (FCG). We present for the first time radial gradients of single-stellar population (SSP) ages and metallicities in a sample of FCGs We took deep spectra with the long-slit spectrograph ISIS at the William Herschel Telescope (WHT) for six FCGs.
2353. Six LMC star forming region spectra
ID:
ivo://CDS.VizieR/J/A+A/600/A16
Title:
Six LMC star forming region spectra
Short Name:
J/A+A/600/A16
Date:
21 Oct 2021
Publisher:
CDS
Description:
The kinetic temperature of molecular clouds is a fundamental physical parameter affecting star formation and the initial mass function. The Large Magellanic Cloud (LMC), the closest star forming galaxy with low metallicity, provides an ideal laboratory to study star formation in such an environment. The classical dense molecular gas thermometer NH_3_ is rarely available in a low metallicity environment because of photoionization and a lack of nitrogen atoms. Our goal is to directly measure the gas kinetic temperature with formaldehyde toward six star-forming regions in the LMC. Three rotational transitions (J_KAKC_ = 3_03_-2_02_, 3_22_-2_21_, and 3_21_-2_20_) of para-H_2_CO near 218GHz were observed with the Atacama Pathfinder EXperiment (APEX) 12m telescope toward six star forming regions in the LMC. Those data are complemented by C^18^O 2-1 spectra.
2354. Six warm metal-poor stars iron abundances
ID:
ivo://CDS.VizieR/J/ApJ/860/125
Title:
Six warm metal-poor stars iron abundances
Short Name:
J/ApJ/860/125
Date:
21 Oct 2021
Publisher:
CDS
Description:
Neutral Fe lines in metal-poor stars yield conflicting abundances depending on whether and how deviations from local thermodynamic equilibrium (LTE) are considered. We have collected new high-resolution and high signal-to-noise ultraviolet (UV) spectra of three warm dwarf stars with [Fe/H]~-2.9 with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. We locate archival UV spectra for three other warm dwarfs with [Fe/H]~-3.3, -2.2, and -1.6, supplemented with optical spectra for all six stars. We calculate stellar parameters using methods that are largely independent of the spectra, adopting broadband photometry, color-temperature relations, Gaia parallaxes, and assumed masses. We use the LTE line analysis code MOOG to derive Fe abundances from hundreds of FeI and FeII lines with wavelengths from 2290 to 6430{AA}. The [Fe/H] ratios derived separately from FeI and FeII lines agree in all six stars, with [FeII/H]-[FeI/H] ranging from +0.00+/-0.07 to -0.12+/-0.09dex, when strong lines and FeI lines with lower excitation potential <1.2eV are excluded. This constrains the extent of any deviations from LTE that may occur within this parameter range. While our result confirms non-LTE calculations for some warm, metal-poor dwarfs, it may not be generalizable to more metal-poor dwarfs, where deviations from LTE are predicted to be larger. We also investigate trends of systematically lower abundances derived from FeI lines in the Balmer continuum region (~3100-3700{AA}), and we conclude that no proposed explanation for this effect can fully account for the observations presently available.
2355. Six year spectroscopy of V2028 Cyg
ID:
ivo://CDS.VizieR/J/A+A/542/A57
Title:
Six year spectroscopy of V2028 Cyg
Short Name:
J/A+A/542/A57
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of nearly six years long spectroscopic observations of the B[e] star V2028 Cyg. The presence of the cold type absorption lines combined with the hot type spectrum indicate a binarity of this object. Since the B[e] stars are embedded in an extended envelope, the usage of common stellar atmosphere models for the analysis is not very appropriate. Therefore we focus on the analysis of the long term spectral line variations in order to determine the nature of this object. We present time dependencies of the equivalent width and radial velocities of the H{alpha} line, [OI] 6300{AA}, FeII 6427, 6433, and 6456{AA} lines. The bisector variations and line intensities are shown for the H{alpha} line. The radial velocities are also measured for the absorption lines of the K component. No periodic variation was found. The observed data show correlations between the measured quantities, which can be used for the future modelling.
2356. SKYLAB S-019 Far-UV Objective-Prism Spectrophotometry
ID:
ivo://CDS.VizieR/III/86
Title:
SKYLAB S-019 Far-UV Objective-Prism Spectrophotometry
Short Name:
III/86
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog contains the ultraviolet flux measurements at wavelengths of 130-420nm, obtained with an objective-prism telescope during the three manned Skylab missions (Skylab 2, 3 and 4) in 1973 and early 1974. The telescope is an f/3 Ritchey-Chretien system with a 15-cm aperture and a calcium fluoride and lithium fluoride focal-plane corrector, and a 4{deg} prism of calcium fluoride. The spectra were obtained in 188 star fields, digitized with a PDS 1010A microdensitometer, and each spectrum was scanned in a series of 30-micron strips. The final catalogue contains 494 spectra on 492 stars, with a resolution of 0.2mn at 140nm, 1.2nm at 200nm, and 5.2nm at 300nm. The data on each star include the adopted fluxes, exposure data, intermediate-band magnitudes, and cross identifications to the Henry Draper Catalogue (Cat. <III/135>).
2357. SLACS. XIII. Galaxy-scale strong lens candidates
ID:
ivo://CDS.VizieR/J/ApJ/851/48
Title:
SLACS. XIII. Galaxy-scale strong lens candidates
Short Name:
J/ApJ/851/48
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the full sample of 118 galaxy-scale strong-lens candidates in the Sloan Lens ACS (SLACS) Survey for the Masses (S4TM) Survey, which are spectroscopically selected from the final data release of the Sloan Digital Sky Survey. Follow-up Hubble Space Telescope (HST) imaging observations confirm that 40 candidates are definite strong lenses with multiple lensed images. The foreground-lens galaxies are found to be early-type galaxies (ETGs) at redshifts 0.06-0.44, and background sources are emission-line galaxies at redshifts 0.22-1.29. As an extension of the SLACS Survey, the S4TM Survey is the first attempt to preferentially search for strong-lens systems with relatively lower lens masses than those in the pre-existing strong-lens samples. By fitting HST data with a singular isothermal ellipsoid model, we find that the total projected mass within the Einstein radius of the S4TM strong-lens sample ranges from 3x10^10^M_{sun}_ to 2x10^11^M_{sun}_. In Shu+ (2015ApJ...803...71S), we have derived the total stellar mass of the S4TM lenses to be 5x10^10^M_{sun}_ to 1x10^12^M_{sun}_. Both the total enclosed mass and stellar mass of the S4TM lenses are on average almost a factor of 2 smaller than those of the SLACS lenses, which also represent the typical mass scales of the current strong-lens samples. The extended mass coverage provided by the S4TM sample can enable a direct test, with the aid of strong lensing, for transitions in scaling relations, kinematic properties, mass structure, and dark-matter content trends of ETGs at intermediate-mass scales as noted in previous studies.
2358. SMC NGC 346-11 and AV 304 spectra
ID:
ivo://CDS.VizieR/J/A+A/436/687
Title:
SMC NGC 346-11 and AV 304 spectra
Short Name:
J/A+A/436/687
Date:
21 Oct 2021
Publisher:
CDS
Description:
An analysis of high-resolution VLT/UVES spectra of two B-type main sequence stars, NGC 346-11 and AV 304, in the Small Magellanic Cloud (SMC), has been undertaken, using the non-LTE TLUSTY model atmospheres to derive the stellar parameters and chemical compositions of each star. The chemical compositions of the two stars are in reasonable agreement. Moreover, our stellar analysis agrees well with earlier analyses of HII regions. The results derived here should be representative of the current base-line chemical composition of the SMC interstellar medium as derived from B-type stars.
2359. S^4^MC project: 6 star forming regions PAHs
ID:
ivo://CDS.VizieR/J/ApJ/744/20
Title:
S^4^MC project: 6 star forming regions PAHs
Short Name:
J/ApJ/744/20
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of mid-infrared spectroscopic mapping observations of six star-forming regions in the Small Magellanic Cloud (SMC) from the Spitzer Spectroscopic Survey of the SMC (S^4^MC). We detect the mid-IR emission from polycyclic aromatic hydrocarbons (PAHs) in all of the mapped regions, greatly increasing the range of environments where PAHs have been spectroscopically detected in the SMC. We investigate the variations of the mid-IR bands in each region and compare our results to studies of the PAH bands in the SINGS sample and in a sample of low-metallicity starburst galaxies. PAH emission in the SMC is characterized by low ratios of the 6-9um features relative to the 11.3um feature and weak 8.6 and 17.0um features. Interpreting these band ratios in the light of laboratory and theoretical studies, we find that PAHs in the SMC tend to be smaller and less ionized than those in higher metallicity galaxies.
2360. SN 2010ae optical spectra
ID:
ivo://CDS.VizieR/J/A+A/561/A146
Title:
SN 2010ae optical spectra
Short Name:
J/A+A/561/A146
Date:
21 Oct 2021
Publisher:
CDS
Description:
A comprehensive set of optical and near-infrared (NIR) photometry and spectroscopy is presented for the faint and fast 2008ha-like supernova (SN) 2010ae.

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