Results 11 to 20 of about 522,601 (266)
The ages of pre-main-sequence stars [PDF]
Monthly Notices of the Royal Astronomical Society, 1999 The position of pre-main-sequence or protostars in the Hertzsprung--Russell diagram is often used to determine their mass and age by comparison with pre-main-sequence evolution tracks. On the assumption that the stellar models are accurate, we demonstrate that, if the metallicity is known, the mass obtained is a good estimate.
Tout, Christopher A. +2 more
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An HST Study of the Substellar Population of NGC 2024
The Astrophysical Journal, 2023 We performed an HST/WFC3-IR imaging survey of the young stellar cluster NGC 2024 in three filters probing the 1.4 μ m H _2 O absorption feature, characteristic of the population of low-mass and substellar-mass objects down to a few Jupiter masses.
Massimo Robberto +8 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
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A Population of Dipper Stars from the Transiting Exoplanet Survey Satellite Mission
The Astrophysical Journal Supplement Series, 2022 Dipper stars are a classification of young stellar objects that exhibit dimming variability in their light curves, dropping in brightness by 10%–50%, likely induced by occultations due to circumstellar disk material.
Benjamin K. Capistrant +14 more
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Pre-Main-Sequence Lithium Depletion [PDF]
, 2006 8 pages, invited review at "Chemical abundances and mixing in stars in the Milky Way and its satellites", eds. L. Pasquini, S. Randich. ESO Astrophysics Symposium (Springer-Verlag)
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GalaxiesWe report new medium-resolution spectroscopy covering the wavelength range from 0.6 to 2.4 μm, as well as multi-epoch, multi-wavelength photometry, of the Class I high-mass embedded young stellar object Mol 12 (IRAS 05373+2349). It is embedded (AV≃12) in
Mauricio Tapia +3 more
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MAGNETIC INTERACTIONS IN PRE-MAIN-SEQUENCE BINARIES [PDF]
The Astrophysical Journal, 2011 Young stars typically have strong magnetic fields, so that the magnetospheres of newly formed close binaries can interact, dissipate energy, and produce synchrotron radiation. The V773 Tau A binary system, a pair of T Tauri stars with a 51 day orbit, displays such a signature, with peak emission taking place near periastron.
Adams, Fred C. +4 more
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Massive pre-main-sequence stars in M17 [PDF]
Proceedings of the International Astronomical Union, 2016 We obtained VLT/X-shooter spectra of twelve candidate young massive stars previously selected by Hanson et al. (1997) in the giant Hii region M17. An analysis of their spectra using FASTWIND models (Puls et al. 2005) shows that they span a mass range of 6 - 20 M⊙.
Ramirez-Tannus, M.C. +8 more
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International Astronomical Union Colloquium, 1993 AbstractThe Pre-Main-Sequence (pre-MS) is defined as the phase following the protostellar stage and ending with the ignition of hydrogen in the stellar core. Models in hydrostatic and thermal equilibrium such as typical “Hayashi track” models are basically adequate to describe the internal structure of pre-MS stars, although for a fraction of pre-MS ...
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Magnetic Activity–Rotation–Age–Mass Relations in Late-pre-main-sequence Stars
The Astrophysical Journal, 2023 We study the four-dimensional relationships between magnetic activity, rotation, mass, and age for solar-type stars in the age range 5–25 Myr. This is the late-pre-main-sequence (l-PMS) evolutionary phase when rapid changes in a star's interior may lead ...
Konstantin V. Getman +2 more
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