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Related papers: Differential rotation in early type stars

200 papers

We investigate the evolution of the surface properties of models for rotating massive stars, i.e., their luminosities, effective temperatures, surface rotational velocities, and surface abundances of all isotopes, from the zero age main…

Astrophysics · Physics 2009-05-29 A. Heger , N. Langer

The atmospheres of weakly-magnetized neutron stars expand hydrostatically and rotate differentially during thermonuclear X-ray bursts. Differential rotation is probably related to the frequency drifts of millisecond burst oscillations…

Astrophysics · Physics 2009-11-10 Kristen Menou

Models of differentially rotating protoneutron stars are calculated, using realistic equations of state of dense hot matter. Various conditions within the stellar interior, corresponding to different stages of protoneutron star evolution,…

Astrophysics · Physics 2008-11-26 J. -O. Goussard , P. Haensel , J. L. Zdunik

Horizontal branch stars should show significant differential rotation with depth. Models that assume systematic angular momentum exchange in the convective envelope and local conservation of angular momentum in the core produce HB models…

Astrophysics · Physics 2009-11-10 Steven D. Kawaler , Shelbi R. Hostler

We determine projected rotation velocities v sini in DAZ white dwarfs, for the first time using the rotational broadening of the CaII K line. The results confirm previous findings that white dwarfs are very slow rotators, and set even more…

Astrophysics · Physics 2009-11-11 L. Berger , D. Koester , R. Napiwotzki , I. N. Reid , B. Zuckerman

The main effect of axial rotation on the evolution of massive PopIII stars is to trigger internal mixing processes which allow stars to produce significant amounts of primary nitrogen 14 and carbon 13. Very metal poor massive stars produce…

Astrophysics · Physics 2008-11-26 G. Meynet , S. Ekstrom , A. Maeder , R. Hirschi , C. Chiappini , C. Georgy

We analyse interferometric data obtained for Regulus with AMBER (Astronomical Multi- BEam combineR) at high spectral resolution ($\lambda/\delta\lambda \approx 12000$) across the Br$\gamma$ spectral line. The study of the photocentre…

Solar and Stellar Astrophysics · Physics 2018-08-07 M. Hadjara , R. G. Petrov , S. Jankov , P. Cruzalèbes , A. Spang , S. Lagarde

We summarize the present status of the predictions of massive star models for the evolution of their surface properties. After discussing luminosity, temperature and chemical composition, we focus on the question whether massive stars may…

Astrophysics · Physics 2007-05-23 Norbert Langer , Alexander Heger

Measured rotational speeds of giant planets and brown dwarfs frequently constitute appreciable fractions of the breakup limit, resulting in centrifugal expansion of these objects at the equator. According to models of internal energy…

Earth and Planetary Astrophysics · Physics 2022-10-26 Mikhail Lipatov , Timothy D. Brandt , Natasha E. Batalha

While many intermediate- and high-mass main sequence stars are rapidly and differentially rotating, the effects of rotation on oscillation modes are poorly known. In this communication we present a first study of axisymmetric…

Solar and Stellar Astrophysics · Physics 2014-11-14 Giovanni M. Mirouh , Clément Baruteau , Michel Rieutord , Jérôme Ballot

In this lecture I discuss the bulk surface heterogeneity of rotating stars, namely gravity darkening. I especially detail the derivation of the omega-model of Espinosa Lara & Rieutord (2011), which gives the gravity darkening in early-type…

Solar and Stellar Astrophysics · Physics 2016-09-07 Michel Rieutord

HD 129929 is a slowly-rotating $\beta$ Cephei pulsator with a rich spectrum of detected oscillations, including two rotational multiplets. The asteroseismic interpretation revealed the presence of radial differential rotation in this…

Solar and Stellar Astrophysics · Physics 2022-08-03 Sébastien Salmon , Facundo Moyano , Patrick Eggenberger , Lionel Haemmerlé , Gaël Buldgen

We present the first measurements of surface differential rotation on a pre-main sequence binary system. Using intensity (Stokes I) and circularly polarised (Stokes V) timeseries spectra, taken over eleven nights at the Anglo-Australian…

The MiMeS project demonstrated that a small fraction of massive stars (around 7%) presents large-scale, stable, generally dipolar magnetic fields at their surface. They are supposed to be fossil remnants of initial phases of stellar…

Solar and Stellar Astrophysics · Physics 2015-06-22 Constance Emeriau , Stéphane Mathis

In rapidly rotating stars Coriolis forces and centrifugal deformations modify the properties of oscillations; the Coriolis force is important for low-frequency modes, while the centrifugal deformation affects mainly p-modes. Here, we…

Solar and Stellar Astrophysics · Physics 2015-06-12 Hideyuki Saio

Differential rotation in stars generates toroidal magnetic fields whenever an initial seed poloidal field is present. The resulting magnetic stresses, along with viscosity, drive the star toward uniform rotation. This magnetic braking has…

Astrophysics · Physics 2009-11-10 James N. Cook , Stuart L. Shapiro , Branson C. Stephens

Magnetic fields at the surface of a few early-type stars have been directly detected. These fields have magnitudes between a few hundred G up to a few kG. In one case, evidence of magnetic braking has been found. We investigate the effects…

Solar and Stellar Astrophysics · Physics 2015-05-20 Georges Meynet , Patrick Eggenberger , Andre Maeder

High precision photometry and spectroscopy of low-mass stars reveal a variety of properties standard stellar evolution cannot predict. Rotation, an essential ingredient of stellar evolution, is a step towards resolving the discrepancy…

Astrophysics · Physics 2007-11-15 D. Brown , M. Salaris , S. Cassisi , A. Pietrinferni

Angular momentum is a key property regulating star formation and evolution. However, the physics driving the distribution of the stellar rotation rates of early-type main-sequence stars is as yet poorly understood. Using our catalog of…

Solar and Stellar Astrophysics · Physics 2021-11-24 Weijia Sun , Xiao-Wei Duan , Licai Deng , Richard de Grijs

The NASA Kepler mission is providing an unprecedented set of asteroseismic data. In particular, short-cadence lightcurves (~60s samplings), allow us to study solar-like stars covering a wide range of masses, spectral types and evolutionary…