Results 51 to 60 of about 183,792 (190)

Absolute Wavelength Shifts - A new diagnostic for rapidly rotating stars [PDF]

open access: yesarXiv, 2003
Accuracies reached in space astrometry now permit the accurate determination of astrometric radial velocities, without any use of spectroscopy. Knowing this true stellar motion, spectral shifts intrinsic to stellar atmospheres can be identified, for instance gravitational redshifts and those caused by velocity fields on stellar surfaces.
arxiv  

Slowing the Spins of Stellar Cores [PDF]

open access: yes, 2019
The angular momentum (AM) evolution of stellar interiors, along with the resulting rotation rates of stellar remnants, remains poorly understood. Asteroseismic measurements of red giant stars reveal that their cores rotate much faster than their surfaces, but much slower than theoretically predicted, indicating an unidentified source of AM transport ...
arxiv   +1 more source

Boron Abundances in Early B Dwarfs of the Galactic Open Cluster NGC 3293

open access: yesThe Astrophysical Journal
New boron abundances or upper limits have been determined for eight early B stars in the young Galactic open cluster NGC 3293, using UV spectra obtained by the Hubble Space Telescope Cosmic Origins Spectrograph.
Charles R. Proffitt   +6 more
doaj   +1 more source

Modeling the Progenitor Stars of Observed Type IIP Supernovae

open access: yesThe Astrophysical Journal
Type IIP supernovae (SNe IIP) are thought to originate from the explosion of massive stars >10 M _⊙ . Their luminosity is primarily powered by the explosion energy and the radioactive decay energy of ^56 Co, with the photosphere location regulated by ...
Kai-An You   +4 more
doaj   +1 more source

Global-scale Simulations of Stellar Convection and their Observational Predictions [PDF]

open access: yesarXiv, 2011
Stars on the lower main sequence (F-type through M-type) have substantial convective envelopes beneath their stellar photospheres. Convection in these regions can couple with rotation to build global-scale structures that may be observable by interferometers that can resolve stellar disks. Here I discuss predictions emerging from 3D MHD simulations for
arxiv  

The Role of Meridional Flow in the Generation of Solar/Stellar Magnetic Fields and Cycles

open access: yesThe Astrophysical Journal
Meridional flow is crucial in generating the solar poloidal magnetic field by facilitating poleward transport of the field from decayed bipolar magnetic regions (BMRs).
Vindya Vashishth, Bidya Binay Karak
doaj   +1 more source

Internal rotation of red giants by asteroseismology

open access: yesEPJ Web of Conferences, 2013
We present an asteroseismic approach to study the dynamics of the stellar interior in red giant stars by asteroseismic inversion of the splittings induced by the stellar rotation on the oscillation frequencies.
Christensen-Dalsgaard J.   +14 more
doaj   +1 more source

Rotational Evolution of Classical T Tauri Stars: Models and Observations

open access: yesThe Astrophysical Journal
We developed a grid of stellar rotation models for low-mass and solar-type classical T Tauri stars (CTTS; 0.3 M _⊙ < M _* < 1.2 M _⊙ ). These models incorporate the star–disk interaction and magnetospheric ejections to investigate the evolution of the ...
Javier Serna   +19 more
doaj   +1 more source

Effects of Rotation on Stellar p-Mode Frequencies [PDF]

open access: yesarXiv, 2011
Effects of stellar rotation on adiabatic oscillation frequencies of pressure modes are discussed. Methods to evaluate them are briefly exposed and some of their main results are presented.
arxiv  

Home - About - Disclaimer - Privacy