Results 41 to 50 of about 3,775,717 (320)
On the Statistical Properties of the Lower Main Sequence [PDF]
The Astrophysical Journal, 2017 Abstract Astronomy is in an era where all-sky surveys are mapping the Galaxy. The plethora of photometric, spectroscopic, asteroseismic, and astrometric data allows us to characterize the comprising stars in detail. Here we quantify to what extent precise stellar observations reveal information about the properties of a star, including ...
Sarbani Basu +5 more
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The Chandra Cygnus OB2 Legacy Survey: Design and X-Ray Point-source Catalog
The Astrophysical Journal Supplement Series, 2023 The Cygnus OB2 association is the largest concentration of young and massive stars within 2 kpc of the Sun, including an estimated ∼65 O-type stars and hundreds of OB stars.
Nicholas J. Wright +7 more
doaj +1 more source
The Instability Strip for Pre--Main-Sequence Stars [PDF]
, 1998 We investigate the pulsational properties of Pre--Main-Sequence (PMS) stars by means of linear and nonlinear calculations. The equilibrium models were taken from models evolved from the protostellar birthline to the ZAMS for masses in the range 1 to 4 ...
Baade D. +9 more
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The Faint End of the Main Sequence [PDF]
The Astrophysical Journal, 1970 New infrared observations of the two faintest known, late M dwarfs, Wolf 359 and +4°4048B (=VB 10) provide accurate luminosities and moderately well-determined temperatures (2500° and 2250° K, respectively). The photometric observations are fitted to a blackbody energy distribution on the assumption that line and band blocking affect most of the ...
Greenstein, Jesse L. +2 more
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, 2015 Images obtained with the Gemini Multi-Object Spectrograph on Gemini South are used to examine the photometric properties and spatial distributions of main sequence (MS) and pre-main sequence (PMS) objects in the star cluster NGC 2401.
Davidge, T. J.
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A non-main-sequence secondary in SY Cancri [PDF]
, 2005 Simultaneous spectroscopic and photometric observations of the Z Cam type dwarf nova SY Cancri were used to obtain absolute flux calibrations. A comparison of the photometric calibration with a wide slit spectrophotometric calibration showed that either ...
Dave V +4 more
core +3 more sources
, 2016 The 4D eigenvector 1 parameter space defined by Sulentic et al. may be seen as a surrogate H-R diagram for quasars. As in the stellar H-R diagram, a source sequence can be easily identified. In the case of quasars, the main sequence appears to be mainly driven by Eddington ratio.
Marziani, Paola +8 more
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HIGH PRECISE EFFECTIVE TEMPERATURES OF 182 MAIN SEQUENCE STARS
Odessa Astronomical Publications, 2008 High precise temperatures (σ = 10 - 15 K) have been determined from line depth ratios for a set of 182 F-K field dwarfs of about solar metallicity (-0.5 < [Fe/H] < +0.4), based on high resolution (R=42 000), high S/N echelle spectra.
S. I. Belik +2 more
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Mass loss in main-sequence B stars
, 2014 We calculate radiatively driven wind models of main-sequence B stars and provide the wind mass-loss rates and terminal velocities. The main-sequence mass-loss rate strongly depends on the stellar effective temperature.
Krticka, Jiri
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Differential rotation on the lower main sequence [PDF]
Astronomische Nachrichten, 2005 AbstractWe compute the differential rotation of main sequence stars of the spectral types F, G, K, and M by solving the equation of motion and the equation of convective heat transport in a mean‐field formulation. For each spectral type the rotation rate is varied to study the dependence of the surface shear on this parameter.
G. Rüdiger, M. Küker
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