J 2019

HD 99458: First time ever Ap-type star as a delta Scuti pulsator in a short period eclipsing binary?

SKARKA, Marek, Petr KABÁTH, Ernst PAUNZEN, Miroslav FEDURCO, Ján BUDAJ et. al.

Basic information

Original name

HD 99458: First time ever Ap-type star as a delta Scuti pulsator in a short period eclipsing binary?

Authors

SKARKA, Marek (203 Czech Republic), Petr KABÁTH (203 Czech Republic), Ernst PAUNZEN (40 Austria), Miroslav FEDURCO (703 Slovakia), Ján BUDAJ (703 Slovakia), Daniel DUPKALA, Jiří Bernard KRTIČKA, Artie P. HATZES (276 Germany), Theodor PRIBULLA (703 Slovakia), Štefan PARIMUCHA (703 Slovakia), Zdeněk MIKULÁŠEK (203 Czech Republic), Eike W. GUENTHER (276 Germany), Silvia SABOTTA (276 Germany), Martin BLAŽEK (203 Czech Republic), Jana DVOŘÁKOVÁ (203 Czech Republic, guarantor, belonging to the institution), Ľubomír HAMBÁLEK (703 Slovakia), Tereza KLOCOVÁ, V. KOLLÁR (703 Slovakia), Emil KUDRNA (703 Slovakia), Miroslav ŠLECHTA and Martin VAŇKO (703 Slovakia)

Edition

Monthly Notices of the Royal Astronomical Society, 2019, 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

References:

RIV identification code

RIV/47813059:19240/19:A0000535

Organization unit

Faculty of Philosophy and Science in Opava

UT WoS

000478053200094

Keywords in English

techniques: photometric; techniques: spectroscopic; binaries: eclipsing; stars: chemically peculiar; stars: individual: HD 99458; stars: oscillations

Tags

Tags

International impact, Reviewed
Změněno: 5/3/2020 20:11, RNDr. Jan Hladík, Ph.D.

Abstract

V originále

We present the discovery of a unique object, a chemically peculiar Ap-type star showing delta Scuti pulsations that, is bound in an eclipsing binary system with an orbital period shorter than 3 d. HD 99458 is therefore a complex astrophysical laboratory opening doors for studying various, often contradictory, physical phenomena at the same time. It is the first Ap star ever discovered in an eclipsing binary. The orbital period of 2.722 d is the second shortest among all known chemically peculiar (CP2) binary stars. Pulsations of delta Scuti type are also extremely rare among CP2 stars and no unambiguously proven candidate has been reported. HD 99458 was formerly thought to he a star hosting an exoplanet, but we definitely reject this hypothesis using photometric observations from the K2 mission and new radial velocity measurements. The companion is a low-mass red dwarf star (M_2 = 0.45(2) M_Sun) on an inclined orbit (i = 73.2(6) deg) that shows only grazing eclipses. The rotation and orbital periods are synchronized, while the rotation and orbital axes are misaligned. HD 99458 is an interesting system deserving of more intense investigations.