An investigation of the rotational properties of magnetic
chemically peculiar stars

J 2017

An investigation of the rotational properties of magnetic chemically peculiar stars

NETOPIL, Martin, Ernst PAUNZEN, Stefan HUEMMERICH and Klaus BERNHARD

Basic information

Original name

An investigation of the rotational properties of magnetic chemically peculiar stars

Authors

NETOPIL, Martin (40 Austria), Ernst PAUNZEN (40 Austria, guarantor, belonging to the institution), Stefan HUEMMERICH (276 Germany) and Klaus BERNHARD (40 Austria)

Edition

Monthly Notices of the Royal Astronomical Society, MALDEN, WILEY, 2017, 0035-8711

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

United Kingdom of Great Britain and Northern Ireland

Confidentiality degree

není předmětem státního či obchodního tajemství

Impact factor

Impact factor: 5.194

RIV identification code

RIV/00216224:14310/17:00095479

Organization unit

Faculty of Science

DOI

http://dx.doi.org/10.1093/mnras/stx674

UT WoS

000402808700020

Keywords in English

stars: chemically peculiar; stars: evolution; stars: magnetic field; stars: rotation

Abstract

V originále

The magnetic chemically peculiar (mCP) stars of the upper main sequence exhibit strong, globally organized magnetic fields that are inclined to the rotational axis and facilitate the development of surface abundance inhomogeneities resulting in photometric and spectroscopic variability. Therefore, mCP stars are perfectly suited for a direct measurement of the rotational period without the need for any additional calibrations. We have investigated the rotational properties of mCP stars based on an unprecedentedly large sample consisting of more than 500 objects with known rotational periods. Using precise parallaxes from the Hipparcos and Gaia satellite missions, well-established photometric calibrations and state-of-the-art evolutionary models, we have determined the location of our sample stars in the Hertzsprung-Russell diagram and derived astrophysical parameters such as stellar masses, effective temperature, radii, inclinations and critical rotational velocities. We have confirmed the conservation of angular momentum during the main sequence evolution; no signs of additional magnetic braking were found. The inclination angles of the rotational axes are randomly distributed, although an apparent excess of fast rotators with comparable inclination angles has been observed. We have found a rotation rate of upsilon/upsilon(crit) >= 0.5 for several stars, whose characteristics cannot be explained by current models. For the first time, we have derived the relationship between mass and rotation rate of mCP stars, and provide an analysis that links mass and rotation with magnetic field strength. Our sample is unique and offers crucial input for forthcoming evolutionary models that include the effects of magnetic fields for upper main sequence stars.

Links

GP14-26115P, research and development project

Name: Vstříc k jednotné škále metalicity pro otevřené hvězdokupy

Investor: Czech Science Foundation

Citovat

NETOPIL, Martin, Ernst PAUNZEN, Stefan HUEMMERICH and Klaus BERNHARD. An investigation of the rotational properties of magnetic chemically peculiar stars. Monthly Notices of the Royal Astronomical Society. MALDEN: WILEY, 2017, vol. 468, No 3, p. 2745-2756. ISSN 0035-8711. Available from: https://dx.doi.org/10.1093/mnras/stx674.

@article{1406898,
   author = {Netopil, Martin and Paunzen, Ernst and Huemmerich, Stefan and Bernhard, Klaus},
   article_location = {MALDEN},
   article_number = {3},
   doi = {http://dx.doi.org/10.1093/mnras/stx674},
   keywords = {stars: chemically peculiar; stars: evolution; stars: magnetic field; stars: rotation},
   language = {eng},
   issn = {0035-8711},
   journal = {Monthly Notices of the Royal Astronomical Society},
   title = {An investigation of the rotational properties of magnetic chemically peculiar stars},
   volume = {468},
   year = {2017}
}

TY  - JOUR
ID  - 1406898
AU  - Netopil, Martin - Paunzen, Ernst - Huemmerich, Stefan - Bernhard, Klaus
PY  - 2017
TI  - An investigation of the rotational properties of magnetic chemically peculiar stars
JF  - Monthly Notices of the Royal Astronomical Society
VL  - 468
IS  - 3
SP  - 2745-2756
EP  - 2745-2756
PB  - WILEY
SN  - 00358711
KW  - stars: chemically peculiar
KW  - stars: evolution
KW  - stars: magnetic field
KW  - stars: rotation
N2  - The magnetic chemically peculiar (mCP) stars of the upper main sequence exhibit strong, globally organized magnetic fields that are inclined to the rotational axis and facilitate the development of surface abundance inhomogeneities resulting in photometric and spectroscopic variability. Therefore, mCP stars are perfectly suited for a direct measurement of the rotational period without the need for any additional calibrations. We have investigated the rotational properties of mCP stars based on an unprecedentedly large sample consisting of more than 500 objects with known rotational periods. Using precise parallaxes from the Hipparcos and Gaia satellite missions, well-established photometric calibrations and state-of-the-art evolutionary models, we have determined the location of our sample stars in the Hertzsprung-Russell diagram and derived astrophysical parameters such as stellar masses, effective temperature, radii, inclinations and critical rotational velocities. We have confirmed the conservation of angular momentum during the main sequence evolution; no signs of additional magnetic braking were found. The inclination angles of the rotational axes are randomly distributed, although an apparent excess of fast rotators with comparable inclination angles has been observed. We have found a rotation rate of upsilon/upsilon(crit) >= 0.5 for several stars, whose characteristics cannot be explained by current models. For the first time, we have derived the relationship between mass and rotation rate of mCP stars, and provide an analysis that links mass and rotation with magnetic field strength. Our sample is unique and offers crucial input for forthcoming evolutionary models that include the effects of magnetic fields for upper main sequence stars.
ER  -

NETOPIL, Martin, Ernst PAUNZEN, Stefan HUEMMERICH and Klaus BERNHARD. An investigation of the rotational properties of magnetic chemically peculiar stars. \textit{Monthly Notices of the Royal Astronomical Society}. MALDEN: WILEY, 2017, vol.~468, No~3, p.~2745-2756. ISSN~0035-8711. Available from: https://dx.doi.org/10.1093/mnras/stx674.

Detailed Information on Publication Record