1 SIAMOIS Sismomètre Interférentiel A Mesurer les Oscillations des Intérieurs Stellaires Asteroseismology in Antarctica at Dome C Benoît Mosser, Michel Auvergne, Thierry Appourchaux, Annie Baglin, Caroline Barban, Claude Catala, Marc-Antoine Dupret, MarieJo Goupil, Jean-Pierre Maillard, Eric Michel, Reza Samadi, Francois-Xavier Schmider, Frédéric Thévenin, Gérard Vauclair et al. Observatoire de Paris (LESIA, GEPI), IAP, IAS, UNSA/LUAN, OMP/LATT, OCA CW9 - SIAMOIS

2 In 2009 has achieved a huge program CW9 - SIAMOIS AND THEN ?

3 Scientific goals Step 1: photometry in space For complementary observations: photometry in space / ground based spectrometric observations Low mass stars Doppler information (limited granulation noise, l = 3 modes) Long term variations Follow up of targets revealed by COROT Questions raised by COROT… In the best site for long-duration continuous observations : at Dome C in Antarctica Solar like oscillations Stellar interior CW9 - SIAMOIS Step 2 … ground-based spectrometry

4 Dome C CW9 - SIAMOIS Duty cycle > 90 % during 3 months

5 Properties at Dome C Wintering: full night = 3 months Duty cycle: > 90 % (Agabi, 2005) Much better performances compared to a network (duty cycle limited to 65%; heavy coordination) Conditions similar to space Properties of Dome C are already OK for asteroseismology ~ Space project Asteroseismology at Dome C: CW9 - SIAMOIS

6 Strategy for Dome C 2009/2010Integrated project : + small telescope + dedicated Fourier Transform seismometer 2010+Spectrometer + spectropolarimeter 2-m class telescope INSU (Astronomy) / Antarctic group: - promotes observations at Dome C - has to identify small size projects to be realized as a first step PNPS (Stellar physics): - promotes the rapid development of a dedicated asteroseismometer to be installed at Dome C CW9 - SIAMOIS

7 Fourier Transform seismometry: the Doppler signal is deduced from a limited portion of the interferogram of the stellar visible spectrum FT seismometry successfully tested with the FTS at CFHT Procyon ( Mosser et al. 1998, A&A 340, 457) Principle of an instrument dedicated to asteroseismology Photon noise limited performances: Q = quality factor ; Ne = photoelectrons + low resolution dispersion ( Mosser et al. 2003, PASP 115, 990) Fourier transform seismometry CW9 - SIAMOIS

8 Performances CW9 - SIAMOIS Photon noise limited performances SIAMOIS at Dome C, 40-cm telescope, 120 hrs, mV = 4, duty cycle = 95% ‘‘SNR’’ of circumpolar targets

9 Asteroseismic targets Observable targets with SIAMOIS and a 40-cm telescope 40-cm tel :- 8 targets F, G and K, IV & V, with solar like oscillations - more than 30 red giants - many  Scuti with v sin i < 20 km/s Program for more than 3 winterovers CW9 - SIAMOIS

10 Project and instrument 40-cm telescope low cost, easy ‘antartization’, dedicated to the projet Interferometer monolithic instrument no moving part, reduced size fiber fed Post-dispersion efficiency, photon noise limited performances CW9 - SIAMOIS

11 Schedule 2004: faisability - Realisation and test of the only critical subsystem 2005: phase A (funded) - Design of the instrument for Antarctic - Integrated project with a small collector - Positive recommendation from the WG of PNPS (stellar physics) 2006: end of phase A + phase B - Design of the full instrument ; thermo-mechanical analysis - Prototype, tests … Transfer at Dome C 2009: winterover at Dome C Interferometer JP Amans GEPI CW9 - SIAMOIS ‘‘Big science’’ at Dome C for < 1 ME