Doradus stars in the SIAMOIS context

Philippe Mathias

Observatoire de la Côte d’Azur

Dept. GEMINI

Generalities

► A7 -- F5 ► V -- IV► g-mode pulsators► ~60 confirmed variables► Periods: 0.3 -- 3 days► Multiperiodic► Flux-blocking mechanism► 50% in binary system► Solar metallicity

Fekel et al. 2005

Large variety of spectra

• OHP survey:

Mathias et al. 2004

g-modes: tangential motions

Kaye et al. 1999

LPV detection

v.sin i = 46 km/s

RV variations

• HD 209295

De Cat et al. 2006

Typical amplitudes

Composite spectra: ~ 10%

Fekel et al. 2003 HD 7169

50% in a binary system

Tidal excitations/ hybrids ?

Warner et al. 2003

Multi-site survey of HD 211699

OHP+KPNO

v.sini=12km/s

Fourier analysis

Hipparcos:f = 0.933 /d

2 others:

1.23 /d1.46 /d

Complementary observations:interferometry

• Ex: HD 147787

• P = 39 d

• e=0.59

• M1/M2 ~ 1

• min ~ 12.3 mas

well resolved by the VLTI

(u,v) plane coverage (ATs)

SIAMOIS targets

• Visibility > 3 months from DOME C

• Moderate v.sin i

(< 20 km/s)• V < 5

27290 4.2 F4 III 55 bf

27377 7.4 F0 V 5.5 c / SB2

55892 4.5 F0 IV 51 bf

103257 6.7 F2 V c

110606 7.9 F2 V 5.8 c / SB2

137785 6.4 F2 V c

147787 5.3 F4 IV 7.6 c / SB2

149989 6.3 A9 V 134 bf

187028 7.5 F0 V 85 bf

197541 7.5 F0 V 29 c

206481 7.9 F0 V c

209295 7.3 F0 V 86 bf / SB / hy

216910 6.7 F2 IV 92 bf

224288 8.0 F0 V

Fortuntately,non exhaustive list!