Solar-like oscillations in Red Giants: Status & Perspectives with SIAMOIS Caroline Barban LESIA/UFE Observatoire de Paris

2 Red giant solar-like oscillations Amplitude > 10 ppm or m/s Period > hours Few modes (10’s) Only radial modes (?)

Solar-like oscillations detections Red giants

Solar-like oscillations in red giants  UMa, K0III WIRE, 37 days  Hz A~ ppm  Hya, K3II-III WIRE, 19 days  Hz A~1000 ppm FEROS over 17 days 243 spectra  Hz ~8  Hz Arcturus, K1.5III Buzasi et al Setiawan et al Retter et al frequency (  Hz) 050

 Hya (G7III,m v =3.54)  Hz A~2 m/s CORALIE, over 1 month 433 Radial Velocity data Autocorrelation ~ 7  Hz 3.07 M  3.15 M  2.93 M  Frandsen et al. 2002

  Coralie/1.2m La silla, Chile Elodie/1.93m OHP, France collaboration Belgique-Suisse-France Solar-like oscillations in  Oph,  Ser Over 74 nights, 635 RV data

 Ser (K0III,m v =3.26)  Hz A~2 m/s ~ 8  Hz ??  -W1-W1 2?2? W1W1 Barban et al., SOGO 2004 Over 74 nights, 1062 RV data Autocorrelation

 Oph (G9.5III,m v =3.24) Autocorrelation W1W1  22 W 1 -2  W1-W1-  W 1 -  2-W12-W1 3-W13-W1 OR Over 74 nights, 635 RV data  Hz A~3 m/s ~ 5 or 7  Hz ~ 5  Hz ~ 7  Hz De Ridder et al. 2006

Red giant observations with MOST

 Oph (G9.5III,m v =3.24) window P oribte - P oribte S-S-S+P oribte S+P oribt -P oribte P oribte duty cycle ~ 50% 28 days

Autocorrelation ~ 5  Hz  Oph (G9.5III,m v =3.24)

Red giant observations with SIAMOIS from DOME C

Possible targets with Siamois

Siamois: red giant simulation window Dome C, 90 days duty cycle ~ 86 % 1 “ideal” site, 90 days 8h/night duty cycle ~ 33 %

Dome C, 90 days duty cycle ~ 86 % 1 “ideal” site, 90 days 8h/night duty cycle ~ 33 % Siamois: red giant simulation Autocorrelation W1W1 <0><0>2

2 Why observing red giants Hydrodynamical simulation (B. Freytag) Samadi et al V max /V max  (L/M) 1.5 (L/M) 1.0 (L/M) 0.8 (L/M) 0.7