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Solar-like oscillations in Red Giants: Status & Perspectives with SIAMOIS Caroline Barban LESIA/UFE Observatoire de Paris. 2. http://www.bramboroson.com/astro/images/hrdiagram.jpg. Red giant solar-like oscillations Amplitude > 10 ppm or m/s Period > hours Few modes (10’s)
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Solar-like oscillations in Red Giants: Status & Perspectives with SIAMOIS Caroline Barban LESIA/UFE Observatoire de Paris
2 http://www.bramboroson.com/astro/images/hrdiagram.jpg 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 WIRE, 37 days 1.8 - 44 Hz A~1-4 105 ppm FEROS over 17 days 243 spectra WIRE, 19 days 4 - 7 Hz A~1000 ppm 50 - 120 Hz <0>~8 Hz Setiawan et al. 2005 Buzasi et al. 2000 UMa, K0III http://homepage.smc.edu/balm_simon/images/astro%201a/post_ms_low_mass/red_giant.gif 0 50 0 frequency (Hz) 5000 Hya, K3II-III Arcturus, K1.5III Retter et al. 2003
Hya(G7III,mv=3.54) CORALIE, over 1 month 433 Radial Velocity data 50 - 130 Hz A~2 m/s Autocorrelation http://homepage.smc.edu/balm_simon/images/astro%201a/post_ms_low_mass/red_giant.gif <0> ~ 7 Hz 3.15 M 3.07 M 2.93 M Frandsen et al. 2002
Coralie/1.2m La silla,Chile Solar-like oscillations in Oph, Ser collaboration Belgique-Suisse-France Elodie/1.93m OHP,France http://homepage.smc.edu/balm_simon/images/astro%201a/post_ms_low_mass/red_giant.gif Over 74 nights, 635 RV data
Ser (K0III,mv=3.26) Over 74 nights, 1062 RV data 80 - 170 Hz A~2 m/s <0> ~ 8 Hz Autocorrelation W1 ? 2? -W1 Barban et al., SOGO 2004
Oph (G9.5III,mv=3.24) 30 - 90 Hz A~3 m/s <0> ~ 5 or 7 Hz Autocorrelation W1 2-W1 W1 - 3-W1 W1- 2 W1-2 Over 74 nights, 635 RV data http://homepage.smc.edu/balm_simon/images/astro%201a/post_ms_low_mass/red_giant.gif OR De Ridder et al. 2006 <0> ~ 7 Hz <0> ~ 5 Hz
Red giant observations with MOST
Oph (G9.5III,mv=3.24) window duty cycle ~ 50% 28 days Poribte -Poribte Poribte - Poribte -S S -S+Poribte S+Poribt
Oph (G9.5III,mv=3.24) Autocorrelation <0> ~ 5 Hz
http://www.ifremer.fr/ifrtp/img/cartes/antarc.jpg Red giant observations with SIAMOIS from DOME C http://www.gdargaud.net/Photo/Panorama.html
Siamois: red giant simulation window Dome C, 90 days duty cycle ~ 86 % window 1 “ideal” site, 90 days 8h/night duty cycle ~ 33 %
Siamois: red giant simulation Autocorrelation <0> 2<0> Dome C, 90 days duty cycle ~ 86 % Autocorrelation 1 “ideal” site, 90 days 8h/night duty cycle ~ 33 % W1
2 Hydrodynamical simulation (B. Freytag) Why observing red giants (L/M)1.5 (L/M)0.8 (L/M)1.0 (L/M)0.7 Vmax/Vmax Samadi et al. 2005