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Related papers: Reddenings of FGK supergiants and classical Cephei…

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We present chemical composition and fundamental parameters (the effective temperature, surface gravity and radius) for four sharp-lined A-type stars ${\gamma}$ Gem (HD 41705), o Peg (HD 214994), ${\theta}$ Vir (HD 114330) and ${\nu}$ Cap…

Solar and Stellar Astrophysics · Physics 2023-09-18 A. M. Romanovskaya , T. A. Ryabchikova , Yu. V. Pakhomov , S. A. Korotin , T. M. Sitnova

Despite observational evidences, InfraRed (IR) excess of classical Cepheids are seldom studied and poorly understood, but probably induces systematics on the Period-Luminosity (PL) relation used in the calibration of the extragalactic…

Cepheid masses continue to be important tests of evolutionary tracks for intermediate mass stars as well as important predictors of their future fate. For systems where the secondary is a B star, {\it Hubble Space Telescope} ultraviolet…

We present new H-band echelle spectra, obtained with the NIRSPEC spectrograph at Keck II, for the massive star cluster "B" in the nearby dwarf irregular galaxy NGC 1569. From spectral synthesis and equivalent width measurements we obtain…

Astrophysics · Physics 2009-11-13 S. S. Larsen , L. Origlia , J. P. Brodie , J. S. Gallagher

I present photometric and radial velocity data for Galactic Cepheids, most of them being in the southern hemisphere. There are 1250 Geneva 7-color photometric measurements for 62 Cepheids, the average uncertainty per measurement is better…

Astrophysics · Physics 2009-11-07 D. Bersier

We present a comparison of low-resolution spectra of 60 stars covering the whole M-dwarf sequence. Using the most recent PHOENIX BT-Settl stellar model atmospheres (see paper by F. Allard, in this book) we do a first quantitative compari-…

Solar and Stellar Astrophysics · Physics 2011-02-09 C. Reyle , A. S. Rajpurohit , M. Schultheis , F. Allard

Cepheids are key distance indicators and benchmarks for stellar evolution, yet most of them are members of binary or multiple systems. While spectroscopic surveys and Gaia proper-motion anomalies reveal a high binary fraction, the…

Solar and Stellar Astrophysics · Physics 2026-04-08 A. Gallenne , P. Kervella , N. R. Evans , J. Milli , E. Sivkova , W. Gieren , G. Pietrzyński , G. Bras , V. Hocdé , W. Kiviaho , N. Nardetto , B. Pilecki , B. Zgírski

We present simultaneous 0.65-2.5 microns medium resolution (3300 < R < 8100) VLT/X-Shooter spectra of the young low-mass (19+/-5MJup) L-T transition object VHS 1256-1257 b, a known spectroscopic analogue of HR8799d. The companion is a prime…

New estimates of the distances of 36 nearby galaxies are presented based on accurate distances of galactic Cepheids obtained by Gieren, Fouque and Gomez (1998) from the geometrical Barnes-Evans method. The concept of 'sosie' is applied to…

Astrophysics · Physics 2009-11-07 G. Paturel , G. Theureau , P. Fouque , J. N. Terry , I. Musella , T. Ekholm

The most recent SH0ES measurement of the Hubble constant employs corrections of type Ia supernova magnitudes due to extinction in their host galaxies. These corrections are estimated using a probabilistic model which is trained on Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Radosław Wojtak , Jens Hjorth

Spectroscopic data are necessary to break degeneracies in asteroseismic modelling of the interior structure in high- and intermediate-mass stars. We derive precise photospheric stellar parameters for a sample of 166 B-type stars with TESS…

Context. B-type supergiants are versatile tools to address various astrophysical topics, ranging from stellar atmospheres over stellar and galactic evolution to the cosmic distance scale. Aims. A hybrid non-LTE approach - line-blanketed…

Solar and Stellar Astrophysics · Physics 2023-01-10 D. Weßmayer , N. Przybilla , K. Butler

We present a compilation of Cepheid distance moduli and data for four secondary distance indicators that employ stars in the old stellar populations: the planetary nebula luminosity function (PNLF), the globular cluster luminosity function…

We aim to improve upon contemporary methods to estimate host-galaxy reddening of stripped-envelope (SE) supernovae (SNe). To this end the Carnegie Supernova Project (CSP-I) SE SNe photometry data release, consisting of nearly three dozen…

We present angular diameters for 42 luminosity class I stars and 32 luminosity class II stars that have been interferometrically determined with the Palomar Testbed Interferometer. Derived values of radius and effective temperature are…

Astrophysics · Physics 2015-05-13 G. T. van Belle , M. J. Creech-Eakman , A. Hart

We have undertaken quantitative analysis of four LMC and SMC O4--9.7 extreme supergiants using far-ultraviolet FUSE, ultraviolet IUE/HSTand optical VLT UVES spectroscopy. Extended, non-LTE model atmospheres that allow for the consistent…

Astrophysics · Physics 2009-11-07 P. A. Crowther , D. J. Hillier , C. J. Evans , A. W. Fullerton , O. De Marco , A. J. Willis

Accurate radial velocities ($v_{\rm rad}$) of Cepheids are mandatory within the context of distance measurements via the Baade-Wesselink technique. The most common $v_{\rm rad}$ derivation method consists in cross-correlating the observed…

In this follow-up paper, we investigate the use of Convolutional Neural Network for deriving stellar parameters from observed spectra. Using hyperparameters determined previously, we have constructed a Neural Network architecture suitable…

Solar and Stellar Astrophysics · Physics 2022-11-01 Marwan Gebran , Frédéric Paletou , Ian Bentley , Rose Brienza , Kathleen Connick

We have observed a large sample of compact planetary nebulae in the near-infrared to determine how the 2^1P-2^1S HeI line at 2.058um varies as a function of stellar effective temperature, Teff. The ratio of this line with HI Br g at 2.166um…

Astrophysics · Physics 2009-10-31 S. L. Lumsden , P. J. Puxley , M. G. Hoare

We rediscuss the temperature of O dwarfs based on new non-LTE line blanketed atmosphere models including stellar winds computed with the CMFGEN code of Hillier & Miller (1998). Compared to the latest calibration of Vacca et al. (1996), the…

Astrophysics · Physics 2010-04-29 F. Martins , D. Schaerer , D. J. Hillier