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Related papers: Granulation in K-type Dwarf Stars. I. Spectroscopi…

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The heavy mass loss observed in evolved asymptotic giant branch stars is usually attributed to a two-step process: atmospheric levitation by pulsation-induced shock waves, followed by radiative acceleration of newly formed dust grains.…

Solar and Stellar Astrophysics · Physics 2017-11-08 S. Bladh , C. Paladini , S. Höfner , B. Aringer

We investigate galactic-scale outflowing winds in 72 star-forming galaxies at z~1 in the Extended Groth Strip. Galaxies were selected from the DEEP2 survey and follow-up LRIS spectroscopy was obtained covering SiII, CIV, FeII, MgII, and MgI…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 K. A. Kornei , A. E. Shapley , C. L. Martin , A. L. Coil , J. M. Lotz , D. Schiminovich , K. Bundy , K. G. Noeske

Granular convective motions reach into the lower solar atmosphere, typically causing photospheric spectral lines to exhibit a differential line shift. This Doppler shift to shorter wavelength is commonly known as convective blueshift. We…

Solar and Stellar Astrophysics · Physics 2019-01-30 Franziska Stief , Johannes Löhner-Böttcher , Wolfgang Schmidt , Tilo Steinmetz , Ronald Holzwarth

An analysis is made of the spectral line shapes of tau Bootis using high resolution (0.026 A) and high signal-to-noise (S/N~400) data in an effort to confirm the planet hypothesis for this star. Changes in the line shape are quantified…

Astrophysics · Physics 2009-10-30 Artie P. Hatzes , William D. Cochran

The detection of Earth-mass exoplanets in the habitable zone around solar-mass stars using the radial velocity technique requires extremely high precision, on the order of 10$\,$cm$\,$s$^{-1}$, below the intrinsic variability of even…

Solar and Stellar Astrophysics · Physics 2021-10-27 F. Liebing , S. V. Jeffers , A. Reiners , M. Zechmeister

Rotational and radial velocities have been measured for 1589 evolved stars of spectral types F, G and K and luminosity classes IV, III, II and Ib, based on observations carried out with the CORAVEL spectrometers. The precision in radial…

Solar and Stellar Astrophysics · Physics 2013-12-20 J. R. De Medeiros , S. Alves , S. Udry , J. Andersen , B. Nordström , M. Mayor

Previous investigations on hydrogen-rich white dwarfs generally yield only very small rotational velocities (v_rot sin i). We have analyzed line profiles in high-resolution optical spectra of eight hydrogen-deficient (pre-) white dwarfs and…

Astrophysics · Physics 2007-05-23 T. Rauch , S. Koeper , S. Dreizler , K. Werner , U. Heber , I. N. Reid

High resolution echelle spectra of PW And (HD~1405) have been taken during eight observing runs from 1999 to 2002. The detailed analysis of the spectra allow us to determine its spectral type (K2V), mean heliocentric radial velocity (V_hel…

Astrophysics · Physics 2009-11-10 J. Lopez-Santiago , D. Montes , M. J. Fernandez-Figueroa , L. W. Ramsey

We present a sequence of high resolution (R~20,000 or 15 km/s) infrared spectra of stars and brown dwarfs spanning spectral types M2.5 to T6. Observations of 16 objects were obtained using eight echelle orders to cover part of the J-band…

Based on the near infrared spectra of 42 M dwarfs, carbon abundances are determined from the ro-vibrational lines of CO 2-0 band. We use Teff values based on the angular diameters if available or apply a logTeff - M3.4 (the absolute…

Solar and Stellar Astrophysics · Physics 2015-06-22 Takashi Tsuji , Tadashi Nakajima

We present the discovery of seven new T dwarfs identified in the Two Micron All Sky Survey. Low-resolution (R$\sim$150) 0.8--2.5 micron spectroscopy obtained with the IRTF SpeX instrument reveal the characteristic H$_2$O and CH$_4$ bands in…

We present Far Ultraviolet Explorer (FUSE) spectra for three Magellanic Cloud O stars (Sk 80, Sk -67 05 and Sk -67 111) with repeated observations. The data demonstrate the capabilities of FUSE to perform time-resolved spectroscopy on…

Radial velocity measurements are presented for 85 late M- and L-type very low mass stars and brown dwarfs obtained with the Magellan Echellette (MagE) spectrograph. Targets primarily have distances within 20 pc of the Sun, with more distant…

We present projected rotational velocities and new measurements of the rotational profile of some 180 nearby stars with spectral types A-F. The overall broadening profile is derived analysing spectral line shape from hundreds of spectral…

Solar and Stellar Astrophysics · Physics 2015-06-04 Matthias Ammler-von Eiff , Ansgar Reiners

High-dispersion IUE data encode significant information about aggregate line absorptions that cannot be conveniently extracted from individual spectra. We apply a new technique in which fluxes from each echelle order of a short wavelength…

Astrophysics · Physics 2009-11-06 Myron A. Smith

Moderate resolution spectra of four globular clusters in the dwarf spheroidal galaxy IKN obtained with the 6-m telescope of the Special Astrophysical Observatory have been used to determine the radial velocities, ages, and metallicities of…

Astrophysics of Galaxies · Physics 2024-06-04 M. E. Sharina , V. V. Shimansky

We present paper six of the NIRSPEC Brown Dwarf Spectroscopic Survey, an analysis of multi-epoch, high-resolution (R~20,000) spectra of 25 field dwarf systems (3 late-type M dwarfs, 16 L dwarfs, and 6 T dwarfs) taken with the NIRSPEC…

Solar and Stellar Astrophysics · Physics 2015-08-06 L. Prato , G. N. Mace , E. L. Rice , I. S. McLean , J. D. Kirkpatrick , A. J. Burgasser , S. S. Kim

We forecast parameter uncertainties on the mass profile of a typical Milky Way dwarf spheroidal (dSph) galaxy using the spherical Jeans Equation and Fisher matrix formalism. We show that radial velocity measurements for 1000 individual…

Astrophysics of Galaxies · Physics 2021-12-13 Juan Guerra , Marla Geha , Louis E. Strigari

Surface granulation can be predicted with the mass, metallicity, and frequency of maximum power of a star. Using the orders-of-magnitude larger APOGEE-Kepler sample, we recalibrate the relationship fit by Corsaro et al. (2017) for…

Solar and Stellar Astrophysics · Physics 2019-10-09 Jamie Tayar , Keivan G. Stassun , Enrico Corsaro

We report evidence for the granulation signal in the star Procyon A, based on two photometric time series from the star tracker on the WIRE satellite. The power spectra show evidence of excess power around 1 milliHz, consistent with the…

Astrophysics · Physics 2009-11-11 H. Bruntt , H. Kjeldsen , D. L. Buzasi , T. R. Bedding