High-velocity CP2 stars in the Galactic halo
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F23%3A00132732" target="_blank" >RIV/00216224:14310/23:00132732 - isvavai.cz</a>
Result on the web
<a href="https://doi.org/10.1051/0004-6361/202245464" target="_blank" >https://doi.org/10.1051/0004-6361/202245464</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1051/0004-6361/202245464" target="_blank" >10.1051/0004-6361/202245464</a>
Alternative languages
Result language
angličtina
Original language name
High-velocity CP2 stars in the Galactic halo
Original language description
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 Galactic disk. However, a small fraction of these objects were recently found to be located far from the Galactic plane and are thought to belong to the Galactic halo, which is unexpected for this class of objects.Aims. Our study investigates the halo membership of the proposed halo CP2 star candidates based on their velocities and Galactic orbits, to determine their points of origin. In addition, we searched for further halo CP2 star candidates using an as-yet-unpublished sample of CP stars.Methods. Our analysis relied on the astrometry from the early third Gaia data release and radial velocities based on the spectroscopy from LAMOST and SDSS, which was also employed in spectral classification. The light variability of the confirmed CP2 stars in our sample was analyzed using data from the ZTF and ATLAS surveys.Results. After filtering our initial sample using kinematic and spectroscopic criteria, we identified six CP2 stars with kinematical properties consistent with a halo membership. The orbits of these stars are in agreement with an origin in the Galactic disk where they were probably ejected through dynamical interactions or in the binary supernova scenario, making them the first runaway CP2 stars known.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10308 - Astronomy (including astrophysics,space science)
Result continuities
Project
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Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2023
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Astronomy and Astrophysics
ISSN
0004-6361
e-ISSN
1432-0746
Volume of the periodical
674
Issue of the periodical within the volume
June 2023
Country of publishing house
FR - FRANCE
Number of pages
12
Pages from-to
1-12
UT code for WoS article
001021296000012
EID of the result in the Scopus database
2-s2.0-85163453753