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Related papers: CH stars at High Galactic Latitudes

200 papers

We present the fourth list with results of the Hamburg/SAO Survey for Emission-Line Galaxies (HSS hereafter, SAO - Special Astrophysical Observatory, Russia). The list is a result of the follow-up spectroscopy conducted with the 6m SAO RAS…

We measured carbon abundances and the $^{12}\mathrm{C}/^{13}\mathrm{C}$ ratio in 31 giant branch stars with previous CN and CH band measurements that span -2.33 $<$ M$_{\rm V}$ $<$ 0.18 in the globular cluster M10 (NGC 6254). Abundances…

Solar and Stellar Astrophysics · Physics 2019-06-14 Z. G. Maas , J. M. Gerber , Alex Deibel , C. A. Pilachowski

Carbon stars (with atmospheric C/O$>1$) range widely in temperature and luminosity, from low mass dwarfs to asymptotic giant branch stars (AGB). The main sequence dwarf carbon (dC) stars have inherited carbon-rich material from an AGB…

Solar and Stellar Astrophysics · Physics 2025-02-03 Benjamin R. Roulston , Naunet Leonhardes-Barboza , Paul J. Green , Evan Portnoi

The high resolution optical spectra of H-deficient stars, R Coronae Borealis stars and H-deficient carbon stars are analyzed by synthesizing the C2 Swan bands (0,1), (0,0), and (1,0) using our detailed line-list and Uppsala model…

Solar and Stellar Astrophysics · Physics 2012-11-28 B. P. Hema , Gajendra Pandey , David L. Lambert

The Century Survey Galactic Halo Project is a photometric and spectroscopic survey from which we select relatively blue stars (V-R<0.30 mag) as probes of the Milky Way halo. The Survey strip spans the range of Galactic latitude 35<b<88 deg,…

Aims. The goal of our survey is to provide accurate and multi-epoch radial velocities, atmospheric parameters (Teff, log g and [M/H]), distances and space velocities of faint Red Clump stars. Methods. We recorded high signal-to-noise (S/N…

Astrophysics of Galaxies · Physics 2015-05-20 T. Saguner , U. Munari , M. Fiorucci , A. Vallenari

The results of a spectral survey of the region of massive star formation DR21OH in the 4-mm wavelength range are presented. Sixty-nine molecules and their isotopologues have been detected, ranging from simple diatomic or triatomic species…

Astrophysics of Galaxies · Physics 2024-01-31 S. V. Kalenskii , E. A. Mikheeva

We present results from a 221.9 ks Chandra exposure of the HDF-N and its vicinity, concentrating on the 8.6' X 8.7' area covered by the Caltech Faint Field Galaxy Redshift Survey (the `Caltech area'). The minimum detectable fluxes in the…

We develop and test a method for the estimation of metallicities ([Fe/H]) and carbon abundance ratios ([C/Fe]) for carbon-enhanced metal-poor (CEMP) stars, based on application of artificial neural networks, regressions, and synthesis…

This study uses archival high frequency continuum data to expand the search for Hypercompact HII regions and determine the conditions at which they appear, as this stage high mass star formation is short-lived and rare. We use 23 GHz…

Carbon stars are excellent kinematic tracers of galaxies and play important roles in understanding the evolution of the Galaxy. Therefore, it is worthwhile to search for them in a large amount of spectra. In this work, we build a new carbon…

Astrophysics of Galaxies · Physics 2023-12-12 Linlin Li , Kecheng Zhang , Wenyuan Cui , Jianrong Shi , Wei Ji , Zhenyan Huo , Yawei Gao , Shuai Zhang , Mingxu Sun

This work purports to model the far infrared gray-body emission in the spectra of high-Galactic-latitude clouds. Several carbonaceous laboratory materials are tested for their fitness as carriers of this modified-black-body emission which,…

Astrophysics of Galaxies · Physics 2015-06-19 Renaud Papoular

Medium resolution spectral analysis of candidate Faint High Latitude Carbon (FHLC) stars from Hamburg/ESO survey has given us the potential to discover objects of rare types. Two primary spectral characteristics of R Coroanae Borealis (RCB)…

Solar and Stellar Astrophysics · Physics 2015-05-20 Aruna Goswami , Drisya Karinkuzhi , N. S. Shantikumar

Low spectral resolution (delta lambda/lambda ~ 50) mid-infrared observations with high angular resolution (0.3--0.5'') using the Long Wavelength Spectrometer on the Keck I Telescope are reported of the nuclei of five highly luminous…

Astrophysics · Physics 2009-11-07 B. T. Soifer , G. Neugebauer , K. Matthews , E. Egami , A. J. Weinberger

Spectra with a high signal-to-noise ratio of 50 stars which are just below the main sequence turnoff and are members of M13 are presented. They yield indices for the strength of the CH and the ultraviolet CN band. There is no evidence for a…

Astrophysics · Physics 2009-10-31 J. G. Cohen

This is the first paper in a series of three where we present the first comprehensive inventory of solid state emission bands observed in a sample of 17 oxygen-rich circumstellar dust shells surrounding evolved stars. The data were taken…

Astrophysics · Physics 2009-11-07 F. J. Molster , L. B. F. M. Waters , A. G. G. M. Tielens , M. J. Barlow

A catalogue of 239 ultra-compact HII regions (UCHIIs) found in the CORNISH survey at 5 GHz and 1.5" resolution in the region $10^{\circ} < l < 65^{\circ}, ~|b| < 1^{\circ}$ is presented. This is the largest complete and well-selected sample…

Astrophysics of Galaxies · Physics 2018-07-25 I. E. Kalcheva , M. G. Hoare , J. S. Urquhart , S. Kurtz , S. L. Lumsden , C. R. Purcell , A. A. Zijlstra

Among stars in Galactic globular clusters the carbon abundance tends to decrease with increasing luminosity on the upper red giant branch, particularly within the lowest metallicity clusters. While such a phenomena is not predicted by…

Solar and Stellar Astrophysics · Physics 2019-04-08 Jeffrey M. Gerber , Michael M. Briley , Graeme H. Smith

Our HST/NICMOS Pa survey of the Galactic center (GC) provides a uniform, panoramic, high-resolution map of stars and ionized diffuse gas in the central 416 arcmin^2 of the Galaxy. This survey was carried out with 144 HST orbits using two…

Astrophysics of Galaxies · Physics 2015-05-28 H. Dong , Q. D. Wang , A. Cotera , S. Stolovy , M. R. Morris , J. Mauerhan , E. A. Mills , G. Schneider , D. Calzetti , C. Lang

CH4 is proposed to be the starting point of a rich organic chemistry. Solid CH4 abundances have previously been determined mostly toward high mass star forming regions. Spitzer/IRS now provides a unique opportunity to probe solid CH4 toward…