Results 51 to 60 of about 11,568,785 (350)
Fundamental Parameters of 87 Stars from the Navy Precision Optical Interferometer [PDF]
, 2017 We present the fundamental properties of 87 stars based on angular diameter measurements from the Navy Precision Optical Interferometer, 36 of which have not been measured previously using interferometry.
E. Baines +7 more
semanticscholar +1 more source
Rotation: a fundamental parameter of massive stars [PDF]
Symposium - International Astronomical Union, 1997 Massive stars are rapid rotators. Equatorial rotation velocities span the range vrot = 100–400 km s−1, with B stars rotating closest to their break-up speed vcrit (Howarth et al. 1997). During the last decade, many observations have revealed unusual surface abundances that may require additional internal mixing (beyond that of simple convection and ...
Langer, Norbert +2 more
openaire +3 more sources
Fundamental parameters and infrared excesses of Tycho–Gaia stars [PDF]
, 2017 Effective temperatures and luminosities are calculated for 1,475,921 Tycho-2 and 107,145 Hipparcos stars, based on distances from Gaia Data Release 1. Parameters are derived by comparing multi-wavelength archival photometry to BT-Settl model atmospheres.
I. McDonald, A. Zijlstra, R. Watson
semanticscholar +1 more source
Horizon-scale tests of gravity theories and fundamental physics from the Event Horizon Telescope image of Sagittarius A ∗ [PDF]
Classical and quantum gravity, 2022 Horizon-scale images of black holes (BHs) and their shadows have opened an unprecedented window onto tests of gravity and fundamental physics in the strong-field regime.
S. Vagnozzi +3 more
semanticscholar +1 more source
Wide Field Multicolor CCD Photometry in the Vicinity of the Open Cluster King 7
Open Astronomy, 2010 We present the results of CCD photometry in the seven-color Vilnius system for 1549 stars down to V ∼16 mag in a 1.5 square degree field around the cluster King 7, at the Perseus and Camelopardalis border.
Zdanavičius J. +3 more
doaj +1 more source
The Angular Diameter and Fundamental Parameters of Sirius A [PDF]
Publications of the Astronomical Society of Australia, 2011 AbstractThe Sydney University Stellar Interferometer (SUSI) has been used to make a new determination of the angular diameter of Sirius A. The observations were made at an effective wavelength of 694.1 nm and the new value for the limb-darkened angular diameter is 6.048 ± 0.040 mas (± 0.66%).
Davis, J +5 more
openaire +5 more sources
FUNDAMENTAL PARAMETERS AND SPECTRAL ENERGY DISTRIBUTIONS OF YOUNG AND FIELD AGE OBJECTS WITH MASSES SPANNING THE STELLAR TO PLANETARY REGIME [PDF]
, 2015 We combine optical, near-infrared, and mid-infrared spectra and photometry to construct expanded spectral energy distributions for 145 field age (>500 Myr) and 53 young (lower age estimate
J. Filippazzo +5 more
semanticscholar +1 more source
Studying the UV Mg II Resonance Lines in 20 Be Stars
Open Astronomy, 2011 Using the GR model, we analyze the UV Mg II resonance lines in the spectra of 20 Be stars of different spectral subtypes, in order to detect the presence of satellite or discrete absorption components. The values of some physical parameters – rotational,
Antoniou A. +3 more
doaj +1 more source
Fundamental Parameters of Cepheids [PDF]
International Astronomical Union Colloquium, 1985 In the two centuries since the discovery of δ Cephei and η Aquilae, the study of Cepheids, and of pulsating stars in general, has become a very important field in astronomy. The usefulness of Cepheids, both as distance indicators and as test objects for stellar astrophysics, has been amply demonstrated, and if one just looks at the flood of papers on ...
openaire +2 more sources
Fundamental Parameters of the W Serpentis Stars [PDF]
International Astronomical Union Colloquium, 1989 AbstractApplication of digital cross-correlation spectroscopy to the spectra of the W Serpentis binaries SX Cas and RX Cas has allowed an accurate determination of the orbits and rotations of the (mass-losing) K-subgiant secondary components. The distortion of the primary radial-velocity curves due to the influence of the prominent accretion disks in ...
J. Andersen +3 more
openaire +2 more sources