The search for roAp stars: null results and new candidates from Stromgren-Crawford photometry

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F18%3A00104474" target="_blank" >RIV/00216224:14310/18:00104474 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985815:_____/18:00499982 RIV/68378271:_____/18:00499982

Výsledek na webu

<a href="http://dx.doi.org/10.1088/1674-4527/18/11/135" target="_blank" >http://dx.doi.org/10.1088/1674-4527/18/11/135</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1674-4527/18/11/135" target="_blank" >10.1088/1674-4527/18/11/135</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The search for roAp stars: null results and new candidates from Stromgren-Crawford photometry

Popis výsledku v původním jazyce

The rapidly oscillating Ap (roAp) stars exhibit pulsational photometric and/or radial velocity variations on time scales of several minutes, which are essential to test current pulsation models as well as our assumptions of atmospheric structure characteristics. In addition, their chemical peculiarity makes them very interesting for probing stellar formation and evolution in the presence of a global magnetic field. To date, a limited number of only 61 roAp stars is known to show photometric variability. On the other hand, a literature survey yields 619 unique stars that have unsuccessfully been searched for variability of this kind. Stromgren-Crawford uvby beta photometry of stars from both subgroups was used to investigate whether there is a selection bias for the investigated stars. We also present new photometric measurements (202 hours on 59 different nights) of 55 roAp candidates. We did not detect any new roAp star. Although our detection limits are comparable to other surveys, we also did not find pulsations in the known roAp star HD 12098, which may be a consequence of temporal amplitude changes. On the other hand, we do find some evidence for photometric variability of beta CrB at its spectroscopically derived pulsation period. From the uvby beta photometry we conclude that the blue border of the roAp instability strip appears observationally well defined, whereas the red border is rather poorly known and studied. Within these boundaries, a total of 4646 candidates were identified which appear worth investigating for short-term pulsational variability.

Název v anglickém jazyce

The search for roAp stars: null results and new candidates from Stromgren-Crawford photometry

Popis výsledku anglicky

The rapidly oscillating Ap (roAp) stars exhibit pulsational photometric and/or radial velocity variations on time scales of several minutes, which are essential to test current pulsation models as well as our assumptions of atmospheric structure characteristics. In addition, their chemical peculiarity makes them very interesting for probing stellar formation and evolution in the presence of a global magnetic field. To date, a limited number of only 61 roAp stars is known to show photometric variability. On the other hand, a literature survey yields 619 unique stars that have unsuccessfully been searched for variability of this kind. Stromgren-Crawford uvby beta photometry of stars from both subgroups was used to investigate whether there is a selection bias for the investigated stars. We also present new photometric measurements (202 hours on 59 different nights) of 55 roAp candidates. We did not detect any new roAp star. Although our detection limits are comparable to other surveys, we also did not find pulsations in the known roAp star HD 12098, which may be a consequence of temporal amplitude changes. On the other hand, we do find some evidence for photometric variability of beta CrB at its spectroscopically derived pulsation period. From the uvby beta photometry we conclude that the blue border of the roAp instability strip appears observationally well defined, whereas the red border is rather poorly known and studied. Within these boundaries, a total of 4646 candidates were identified which appear worth investigating for short-term pulsational variability.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2018

Kód důvěrnosti údajů

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

Název periodika

Research in Astronomy and Astrophysics

ISSN

1674-4527

e-ISSN

—

Svazek periodika

18

Číslo periodika v rámci svazku

11

Stát vydavatele periodika

CN - Čínská lidová republika

Počet stran výsledku

12

Strana od-do

1-12

Kód UT WoS článku

000448829000005

EID výsledku v databázi Scopus

2-s2.0-85056100895