Prsentation PowerPoint

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SIAMOIS Sismomètre Interférentiel A Mesurer les
Oscillations des Intérieurs Stellaires Seismic
Interferometer to Measure Oscillations in the
Interior of Stars
Benoît Mosser, Tristan Buey, Claude Catala,
Michel Auvergne, Thierry Appourchaux, Annie
Baglin, Caroline Barban, Marc-Antoine Dupret,
MarieJo Goupil, Jean-Pierre Maillard, Eric
Michel, Reza Samadi, Francois-Xavier Schmider,
Frédéric Thévenin, Gérard Vauclair, Denis Fappani
et al.   Observatoire de Paris/LESIA, IAS,
UNSA/LUAN, OMP/LATT, IAP, OCA
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Asteroseismology
What asteroseismology teaches us ? . Example of
the Sun

• The Sun without asteroseismic constraints !

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Asteroseismology
What asteroseismology teaches us ? . Example of
the Sun

• The Sun without asteroseismic constraints !

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Asteroseismology after COROT
1st step photometry, space-based
observations 2nd step spectrometry,
ground-based obs.

• Complementary observations
• Bright stars
• Low mass stars
• Doppler signal
• ?reduced granulation noise, modes l3

Scientific specifications continuous
observations, long duration
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SIAMOIS at Dome C
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Scientific program
Observable targets with SIAMOIS and a 40-cm
telescope dedicated to the project
COROT

• 40-cm telescope
• - 7 targets, type F, G, K class IV V
• - many red giants d Scuti (v sin i lt 20 km/s)
• ? Scientific programme for more than 6 winterings

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Overall description

• Divided in four sub-systems
• A dedicated Telescope with its Bonnette
  (telescope guiding and fiber coupling).
• An Interferometer and a Camera.
• A structure for thermal and mechanical control.
• A command/control software system.
• Divided in five laboratories
• GIGT from OMP (Observatoire Midi-Pyrennée).
• LUAN from OCA (Observatoire Côte dAzur).
• IAS (Institut dAstrophysique Spatiale).
• LESIA from OPM (Observatoire Paris-Meudon).
• CSIC from Institutode Astrofisica de Andalusia
  (in discussion).
• One associated private contractor
• SESO (Société Européenne de Systèmes Optiques).

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Instrument
Dedicated Telescope Bonnette
Vacuum pump
Thermo-mechanical structure.
Optical bench.
Optical fibers signal and calibration
Interferometer
Camera
Calibration
Command/control system Acquisition,image
processing
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Instrument

• 40-cm telescope low cost, easy antarctization,
  dedicated to the projet
• Interferometer monolithic instrument
• no moving part, reduced size
• fiber fed
• Post-dispersion efficiency, photon noise limited
  performances

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The constraints.

• Small budget and short planning
• High reability of the instrument
• Observation requirements 90 of duty cycle.
• Very difficult to fix anything at Dome C in
  Antarctica.
• Very easy to use
• Not easy set-up at Dome C in Antarctica (once
  again -) ).
• Wintering will insure a minimal maintenance.
• Rather hard environmental conditions
• Shocks and temperature (level and gradient)
  during transportation and storage.
• Temperature, humidity and pressure during
  operation.

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Planning

• 2004
• design
• Achievement of the feasibility phase.
• 2006
• thermo-mechanical analysis
• Qualification tests.
• 2007
• PDR
• FDR
• 2008
• integration
• 2009
• tests
• summer campaign Dome C
• 2010
• - first winterover at Dome C
• Laboratories LESIA (Obs. Paris), IAS (Orsay),
  LUAN (Nice), LATT (Toulouse) SESO

SIAMOIS Interferometer JP Amans, GEPI, Obs Paris
Coast 860 k Including ANR 460 k For
phase A in 2006 (ACI CSA PNPS) 116 k
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Development Philosophy

• Step I Establish all the requirements of the
  sub-systems and the interfaces between them.
• Step II Develop the test benches and
  equipments, write the invitation to tender for
  the industrial contractors.
• Step III Develop the sub-systems (industries
  and laboratories) or buy them directly when
  possible (budget and specifications).
• Step IV Individual acceptance of each
  sub-systems.
• Step V Environmental qualification.
• Step VI Integration of the sub-systems together
  up to the instrument level.
• Step VII End-to-end test in laboratory and on
  the sky, final setup.
• Step VIII After transportation to Dome-C,
  simple integrity test.
• Some revue are foreseen during the project
  development.
• Like space instrument development quality,
  management of configuration, documentation,
  revues with limitations!

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Conclusion

• Dome C a unique site for asterosismology
• 3-month continuous observation with duty cycle
  90
• A specific scientific program after
• High performances with a 40-cm collector
• Pioneering project at Dome C
• FT seismometry suitable concept for installation
  and setup at Dome C
• Multiplex advantage of FT spectrometry
• Small instrument lt 300kg, lt 2m3, lt 1kW,
• Rather fast development with a demonstrate
  feasibility.

siamois
Big science  at Dome C with a budget lt 1 M