2022A&A...657A..27M


Query : 2022A&A...657A..27M

2022A&A...657A..27M - Astronomy and Astrophysics, volume 657A, 27-27 (2022/1-1)

A Kepler K2 view of subdwarf A-type stars.

MOSENLECHNER G., PAUNZEN E., PELISOLI I., SEELIG J., STIDL S. and MAITZEN H.M.

Abstract (from CDS):

Context. The spectroscopic class of subdwarf A-type (sdA) stars has come into focus in recent years because of their possible link to extremely low-mass white dwarfs, a rare class of objects resulting from binary evolution. Although most sdA stars are consistent with metal-poor halo main-sequence stars, the formation and evolution of a fraction of these stars are still matters of debate. Aims. The identification of photometric variability can help to put further constraints on the evolutionary status of sdA stars, in particular through the analysis of pulsations. Moreover, the binary ratio, which can be deduced from eclipsing binaries and ellipsoidal variables, is important as input for stellar models. In order to search for variability due to either binarity or pulsations in objects of the spectroscopic sdA class, we have extracted all available high precision light curves from the Kepler K2 mission. Methods. We have performed a thorough time series analysis on all available light curves, employing three different methods. Frequencies with a signal-to-noise ratio higher than four have been used for further analysis. Results. From the 25 targets, 13 turned out to be variables of different kinds (i.e., classical pulsating stars, ellipsoidal and cataclysmic variables, eclipsing binaries, and rotationally induced variables). For the remaining 12 objects, a variability threshold was determined.

Abstract Copyright: © ESO 2021

Journal keyword(s): subdwarfs - white dwarfs - binaries: general - stars: evolution - stars: variables: general

Simbad objects: 9

goto Full paper

goto View the references in ADS

Number of rows : 9
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023
#notes
1 V* HV And CV* 00 40 55.3833704472 +43 24 59.466999960   15.582 15.599 16.131   ~ 26 0
2 HE 0120+0042 HB* 01 22 58.2108232656 +00 58 16.364521992   15.395 15.457 15.738   A0.8 8 0
3 UCAC4 588-034602 HB* 06 44 41.8460184264 +27 30 54.427192344   14.86 14.66 14.76   ~ 3 0
4 UCAC4 537-033887 V* 06 49 24.4973285592 +17 15 23.832106344       14.44   ~ 2 0
5 GALEX J082003.3+173914 HS* 08 20 03.3574335672 +17 39 14.247846900           sdB+? 11 0
6 GALEX J082447.2+221113 HS* 08 24 47.3040154224 +22 11 13.004671632           sdB+? 7 0
7 Cl* NGC 2632 KP 303144 RR* 08 33 08.8073232480 +23 27 09.789559848     14.03 13.747   ~ 8 0
8 UCAC4 524-048824 CV? 09 01 13.5078126696 +14 47 04.661585376   16.316 16.199 16.073   ~ 9 0
9 BD+39 3858 SB* 19 36 09.0319649832 +39 37 42.946694508   10.11 9.76   9.376 F1V 27 1

To bookmark this query, right click on this link: simbad:objects in 2022A&A...657A..27M and select 'bookmark this link' or equivalent in the popup menu


2023.01.30-23:28:38

© Université de Strasbourg/CNRS

    • Contact