K2 observations of 95 Vir: delta Scuti pulsations in a chromospherically active star

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F17%3A00099898" target="_blank" >RIV/00216224:14310/17:00099898 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1093/mnras/stx591" target="_blank" >http://dx.doi.org/10.1093/mnras/stx591</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/mnras/stx591" target="_blank" >10.1093/mnras/stx591</a>

Jazyk výsledku

angličtina

Název v původním jazyce

K2 observations of 95 Vir: delta Scuti pulsations in a chromospherically active star

Popis výsledku v původním jazyce

We have searched for photometric variability in 95 Vir, a fast rotating, chromospherically active early F-type star, which was observed in the framework of Campaign 6 of the Kepler K2 mission. Available literature information on 95 Vir was procured, and well-established calibrations were employed to verify the derived astrophysical parameters. We have investigated the location of our target star in the M-Bol versus log T-eff diagram, which provides information on the evolutionary status. We have discussed our results in detail, drawing on literature information and the theoretical predictions of state-of-the-art pulsation models, with the aim of unravelling the underlying variability mechanisms. From an analysis of 3400 long-cadence measurements, we have identified two main frequencies and several harmonics in our target star. We attribute the main frequency, f1 = 9.537 28 d(-1), to delta Scuti pulsations. The origin of the secondary signal, f2 = 1.071 29 d(-1), is less clear. We have investigated three possible interpretations of the low-frequency variation: binarity, pulsation and rotational modulation. Current evidence favours an interpretation of f 2 as a signature of the rotational period caused by the presence of cool star-spots, which goes along well with the observed chromospheric activity. However, phase-resolved spectroscopy is needed to verify this assumption. We briefly consider other chromospherically active delta Scuti stars that have been presented in the literature. A search for star-spot-induced photometric variability in these objects might be of great interest, as well as an investigation of the interplay between chromospheric and pulsational activity.

Název v anglickém jazyce

K2 observations of 95 Vir: delta Scuti pulsations in a chromospherically active star

Popis výsledku anglicky

We have searched for photometric variability in 95 Vir, a fast rotating, chromospherically active early F-type star, which was observed in the framework of Campaign 6 of the Kepler K2 mission. Available literature information on 95 Vir was procured, and well-established calibrations were employed to verify the derived astrophysical parameters. We have investigated the location of our target star in the M-Bol versus log T-eff diagram, which provides information on the evolutionary status. We have discussed our results in detail, drawing on literature information and the theoretical predictions of state-of-the-art pulsation models, with the aim of unravelling the underlying variability mechanisms. From an analysis of 3400 long-cadence measurements, we have identified two main frequencies and several harmonics in our target star. We attribute the main frequency, f1 = 9.537 28 d(-1), to delta Scuti pulsations. The origin of the secondary signal, f2 = 1.071 29 d(-1), is less clear. We have investigated three possible interpretations of the low-frequency variation: binarity, pulsation and rotational modulation. Current evidence favours an interpretation of f 2 as a signature of the rotational period caused by the presence of cool star-spots, which goes along well with the observed chromospheric activity. However, phase-resolved spectroscopy is needed to verify this assumption. We briefly consider other chromospherically active delta Scuti stars that have been presented in the literature. A search for star-spot-induced photometric variability in these objects might be of great interest, as well as an investigation of the interplay between chromospheric and pulsational activity.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

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OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Monthly Notices of the Royal Astronomical Society

ISSN

0035-8711

e-ISSN

—

Svazek periodika

468

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

7

Strana od-do

2017-2023

Kód UT WoS článku

000399429600059

EID výsledku v databázi Scopus

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