Aiying ZHOU 周 爱 英

2010.03.31 Beijing

National Astronomical Observatories, CAS

—— Several Observational Aspects

Every star varies ！

Light variations seems universal & much interesting

RRab

What are the Most Interesting Light Curves?

Orbital motion

Puls.

(A)

LC for the parent star of

CoRoT-exo-2b, 1.4RJ, 3.5MJ, 140d, ±0m.00016

78 transitsPorb =1d.74

Solar-like oscillation

Eclipsing Binaries with

Pulsating Components

Interests in such studies If no mechanism damping pulsations in close

binaries, percentage of pulsating stars expected among A-F components of detached & semi-detached eclipsing binaries should be at least the same as for single A-F type stars.

Pulsation characteristics of such systems are similar to those of single pulsators, but their evolutions are quite different due to mass accretion.

Advantages in such studies

Possibility of precise mass and radius determinations Possibility of mode identification during the eclipse o

rbital phases using the observed pulsational amplitude and phase changes (Nather & Robinson 1974, ApJ, 190, 637).

Precise estimation of the accretion rate using the pulsation period changes of the gainer/accreting star caused by accretion.

…… Ref.: 1. Aerts et al. 2004, ASP Conf. Ser. 318, 325

2. Lampens P. 2006, ASP Conf. Ser. 349, 153

δScuti in an Algol-type binary (oEA): AB Cas

Orbital motion

Puls. (A)

The A-F spectral type, mass-accreting, main-sequence pulsating stars in semi-detached Algol-type eclipsing binary systems, i.e. oscillating EA (oEA)

They cataloged:

25 DCST-type oEA:

20 semidetached +4 detached +1 unclassified

90 semidetached + 71 detached + 36 from Hipparcos

in theδScuti region of H-R diagram.

25 +197

How many now ?

In summary, > 72, DSCT–type oEA

> 100, All kinds, oscillating E. B.

> 420, various binary/multiple stellar systems with Puls. Comp.

0

10

20

30

40

50

60

70O A0

A1

A2

A3

A4

A5

A6-

9

B1-

4

B5-

7

B8

B9

F0

F1-

4

F5-

7

F8-

9 G K M

Interesting works

How can binarity modify the pulsational properties? In what manner?

How can binarity/multiplicity help to identify the pulsation modes?

Search for pulsating M,K giants and subgaint stars in E. B.

Search for extra-solar planets around a pulsator. Search for extragalactic E. B. with Puls. Comp. Search for RR in E. B.

Summary

Why

Statistics

Furture works

This talk is based on

Zhou A.-Y., 2010, arXiv:1002.2729 (to be updated)