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Related papers: Chemically peculiar stars on the pre-main sequence

200 papers

We review the interaction in intermediate and high mass stars between their evolution and magnetic and chemical properties. We describe the theory of Ap-star `fossil' fields, before touching on the expected secular diffusive processes which…

Massive star formation exhibits an extremely rich chemistry. However, not much evolutionary details are known yet, especially at high spatial resolution. Therefore, we synthesize previously published Submillimeter Array…

Astrophysics · Physics 2009-11-13 H. Beuther , Q. Zhang , E. A. Bergin , T. K. Sridharan

The upper main sequence magnetic chemically peculiar (Ap) stars exhibit a non-uniform distribution of chemical elements across their surfaces and with height in their atmospheres. These inhomogeneities, responsible for the conspicuous…

Solar and Stellar Astrophysics · Physics 2015-05-20 Oleg Kochukhov

Ap/Bp stars are magnetic chemically peculiar early A and late B type stars of the main sequence. They exhibit peculiar surface abundance anomalies that are thought to be the result of gravitational settling and radiative levitation. The…

Astrophysics · Physics 2007-05-23 S. Turcotte

The magnetic chemically peculiar (mCP) stars of the upper main sequence are perfectly suited to studying the effects of rotation, diffusion, mass-loss, accretion, and pulsation in the presence of an organized stellar magnetic field.…

Solar and Stellar Astrophysics · Physics 2022-11-16 E. Paunzen , M. Prisegen

The recently re-discovered open cluster Stock 2, located roughly 375 pc away and about 400 Myr old, has the potential to be an exciting new testbed for our understanding of stellar evolution. We present results from a spectroscopic campaign…

Solar and Stellar Astrophysics · Physics 2022-11-30 Laia Casamiquela , Marwan Gebran , Marcel Agüeros , Hervé Bouy , Caroline Soubiran

Chemically Peculiar (CP) stars have been subject of systematic research since more than 50 years. With the discovery of pulsation of some of the cool CP stars, the availability of advanced spectropolarimetric instrumentation and high…

Pulsational variability is observed in several types of main sequence stars with anomalous chemical abundances. In this contribution I summarize the relationship between pulsations and chemical peculiarities, giving special emphasis to…

Astrophysics · Physics 2015-05-13 O. Kochukhov

With the aim to corroborate the result of a search for chemically peculiar stars in the Large Magellanic Cloud (LMC) we present measurements obtained from CCD-imaging of two fields, one containing a young open cluster (NGC 1711). While for…

Astrophysics · Physics 2009-11-13 E. Paunzen , O. I. Pintado , H. M. Maitzen , A. Claret

A variety of magnetohydrodynamic mechanisms that may play a role in magnetic, chemically peculiar (mCP) stars is reviewed. These involve dynamo mechanisms in laminar flows as well as turbulent environments, and magnetic instabilities of…

Astrophysics · Physics 2008-01-30 R. Arlt

Magnetic chemically peculiar (mCP) stars allow the investigation of such diverse phenomena as atomic diffusion, magnetic fields and stellar rotation. The aim of the present investigation is to enhance our knowledge of the rotational…

Astrophysics of Galaxies · Physics 2020-02-26 Klaus Bernhard , Stefan Huemmerich , Ernst Paunzen

Growing evidence shows that most stars in the Milky Way, including the Sun, are born in high-mass star-forming regions, but due to both observational and theoretical challenges, our understanding of their chemical evolution is much less…

Astrophysics of Galaxies · Physics 2025-11-19 Francesco Fontani , Maria Teresa Beltrán , Anton Vasyunin

Context. The second subclass of chemically peculiar stars, the CP2 stars, are early-type stars exhibiting anomalous abundances with variable line strengths possibly also accompanied by photometric variability that typically belong to the…

Astrophysics of Galaxies · Physics 2023-06-28 Nikola Faltová , Michal Prišegen , Klaus Bernhard , Stefan Hümmerich , Ernst Paunzen

Since the discovery of the spectral peculiarities of their prototype alpha2 Canum Venaticorum in 1897, the so-called ACV variables, which are comprised of several groups of chemically peculiar stars of the upper main sequence, have been the…

Solar and Stellar Astrophysics · Physics 2021-05-12 E. Paunzen , J. Supikova , K. Bernhard , S. Huemmerich , M. Prisegen

Recently, with the goal to study multiplicity of chemically peculiar stars, we carried out a survey of 40 stars using diffraction limited near infrared (IR) imaging with NAOS-CONICA (NACO) at the VLT. Here, we announce the detection of 27…

Astrophysics · Physics 2007-05-23 S. Hubrig , N. Ageorges , M. Schoeller

Magnetic A stars represent about $5\%$ of the upper main sequence stars and exhibit highly ordered, very stable and often very strong magnetic fields. They frequently show both, brightness- and spectral line profile variations synchronised…

Solar and Stellar Astrophysics · Physics 2014-02-19 Theresa Lueftinger

We present $\gtrsim 15,000$ metal-rich (${\rm [Fe/H]}>-0.2$dex) A and F stars whose surface abundances deviate strongly from Solar abundance ratios and cannot plausibly reflect their birth material composition. These stars are identified by…

The magnetic Ap or CP2 stars are natural atomic and magnetic laboratories and ideal testing grounds for the evaluation of model atmospheres. CP2 stars exhibiting photometric variability are traditionally referred to as alpha2 Canum…

Solar and Stellar Astrophysics · Physics 2016-10-27 Stefan Hümmerich , Ernst Paunzen , Klaus Bernhard

This talk is devoted to the statistical analysis of the new catalogue of Chemically Peculiar stars compiled from papers, where chemical abundances of those stars were given. The catalogue contains chemical abundances and physical parameters…

Solar and Stellar Astrophysics · Physics 2018-12-13 S. Ghazaryan , G. Alecian , A. A. Hakobyan

The paper presents the first results of the ongoing spectropolarimetric monitoring of magnetic fields of stars, whose chemically peculiar nature has been previously revealed with the 1-m SAO RAS telescope. We selected the sample candidates…

Solar and Stellar Astrophysics · Physics 2023-07-26 I. A. Yakunin , E. A. Semenko , I. I. Romanyuk , A. V. Moiseeva , V. N. Aitov