Results 11 to 20 of about 216,058 (291)

The Pre-main Sequence: Challenges and Prospects for Asteroseismology

open access: yesFrontiers in Astronomy and Space Sciences, 2022
Stars do not simply pop up on the main sequence. Before the stars arrive on the zero-age main sequence, they form in the collapses of molecular clouds, gain matter through accretion processes, and compress their cores until hydrogen can burn in full ...
Konstanze Zwintz, Thomas Steindl
doaj   +1 more source

Pre-main sequence stars in LH 91

open access: yesAstronomy & Astrophysics, 2022
Aims. We study the accretion properties of pre-main sequence (PMS) low-mass stars in the LH 91 association within the Large Magellanic Clouds. Methods. Using optical multiband photometry obtained with the Hubble Space Telescope, we identify 75 candidates showing Hα excess emission above the 3σ level with equivalent width EWHα ⩾ 10 Å.
R. Carini   +5 more
openaire   +2 more sources

Abundance anomalies in pre-main-sequence stars: Stellar evolution models with mass loss [PDF]

open access: yes, 2003
The effects of atomic diffusion on internal and surface abundances of A and F pre-main-sequence stars with mass loss are studied in order to determine at what age the effects materialize, as well as to further understand the processes at play in HAeBe ...
Vick, M.   +3 more
core   +12 more sources

The Chandra Cygnus OB2 Legacy Survey: Design and X-Ray Point-source Catalog

open access: yesThe 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

A Low-mass, Pre-main-sequence Eclipsing Binary in the 40 Myr Columba Association—Fundamental Stellar Parameters and Modeling the Effect of Star Spots

open access: yesThe Astronomical Journal, 2023
Young eclipsing binaries (EBs) are powerful probes of early stellar evolution. Current models are unable to simultaneously reproduce the measured and derived properties that are accessible for EB systems (e.g., mass, radius, temperature, and luminosity).
Benjamin M. Tofflemire   +14 more
doaj   +1 more source

A Population of Dipper Stars from the Transiting Exoplanet Survey Satellite Mission

open access: yesThe 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
doaj   +1 more source

PRE-MAIN SEQUENCE EVOLUTIONS OF SOLAR ABUNDANCE LOW MASS STARS [PDF]

open access: yesJournal of Astronomy and Space Sciences, 2007
We present the Pre-Main Sequence (PMS) evolutionary tracks of stars with 0.065~5.0M_⨀. The models were evolved from the PMS stellar birthline to the onset of hydrogen burning in the core.
Youn Kil Jung, Y. -C. Kim
doaj   +1 more source

Walkaway Star Candidates in IC 348 and Their Possible Birthplaces

open access: yesThe Astrophysical Journal, 2023
Observations and theories reveal that star-forming regions eject their members during the early evolution of the cluster. We present an initial search for stars ejected from the young cluster IC 348 based on an analysis of Gaia EDR3 astrometry of ...
Xingyu Zhou   +4 more
doaj   +1 more source

A Study of ISO Spectra for Herbig Ae/Be Stars [PDF]

open access: yesJournal of Astronomy and Space Sciences, 2002
We present the infrared spectra of Herbig Ae/Be stars including the Infrared Space Observatory (ISO) data. To investigate the overall properties of their circumstellar dust envelope and/or disk, we combine the IR spectra with photometric data ranging ...
Kyung-Won Suh, Mi-Ryang Kim, Ji-Hye Baek
doaj   +1 more source

Pre-mainsequence stellar evolution in N-body models [PDF]

open access: yes, 2014
We provide a set of analytic fits to the radii of pre-mainsequence stars in the mass range 0.1 < M/Msun < 8.0. We incorporate the formulae in N-body cluster models for evolution from the beginning of pre-main sequence. In models with 1,000 stars and high
Aarseth, Sverre J.   +2 more
core   +1 more source

Home - About - Disclaimer - Privacy