1. LUAN OCA F.X Schmider, A. Domiciano, R. Petrov, S. Jankov G. Berthomieu, P. Mathias, J. Provost, F. Thevenin C. Catala Measurement of diameter and rotation of seismology primary targets with AMBER

2. What we want to measure through interferometry Fundamental parameters –Diameter –Oblateness –Differential rotation –Inclination angle Detection and characterisation of oscillation modes –Single mode identification –Intermediate degree modes –High degree modes

3. AMBER characteristics 3 Telescopes instrument K, H and J bands Single mode Dispersed fringes Spectral resolutions 35, 1000, 10000 Limiting magnitude with UTs: K>11 specification: absolute visibility accuracy < 1% goal: visibility accuracy = 0.1% specification: differential phase accuracy < 10 -3 radians goal: differential phase accuracy < 10 -4 radians  Commissioning in H and K medium resolution in April 2004, high resolution in October 2004  First open period second semester 2005, with the UT  Fully operational (3 AT, BCD) second semester 2006?  Fringe tracking (FINITO) is not working properly. Magnitude limit is 7 with AT  Relative precision are better than 0.5% for individual measurements  Absolute visibilities are biased by calibration uncertainties AMBER/VLTI Present Status

4. diameter is calculated as a parameter of a model of the ratio of visibilities for the various bases Differential visibilities and diameters (using BCD = Beam Commuter Device) 3 AT, 3 bases BCD low resolution (R=35) JHK band

5. Visibilities of COROT targets baseline =180 m, J Precision on visibility limited by: instrumental stability limb darkening model Uniform disk model Limb darkening model smallest largest diameter of main COROT targets HD 43587 HD 49933 Precision on diameter: depends on visibility slope

6. Parallax and angular diameter of primary targets StarMvKSpect parallax rhoVrot HD435875.714.6F9V 51.7 mas .78 0.59 mas< 6 km/s HD494345.755.0F1V 25.0 mas .75 0.34 mas79 km/s HD499335.784.9F2V 33.5 mas .84 0.40 mas 9 km/s HD522656.845.1G0V 35.63 mas .84 0.31 mas <3 km/s HD1705806.696.5B2V 1.17 mas .80 ~0.09 mas <5 km/s HD1718345.444.6F3V 31.5 mas .75 0.45 mas 64 km/s HD1775526.535.8F1V 22.3 mas .80 0.27 mas 41 km/s HD1806428.298B1.5 II-III 2.08 mas .98 ~0.05 mas HD1815557.527A5 9.55 mas  1.0 0.16 mas170 km/s error on diameter dominated by error on parallax BUT small error on  : relation between T eff and m V (independent estimate of T eff )  2R / d typical relative error on  = 0.2-0.3% for  ≥ 0.3 mas

7. 5 km/s 10 km/s 25 km/s Spectrum 5 km/s 10 km/s 25 km/s Differential phase measurement and photocenter displacement spectroscopic profile photocenter displacement: depends on diameter, vsini

8. 3 AT perpendicular baselines high resolution spectroscopy (R=15000) if vsini is already known from spectroscopy, we can determine diameter very efficient for stars with high vsini, even for small angular diamaters (e.g. HD181555) Proposed set-up for rotation measurement photocenter displacement: depends on diameter & vsini

9. Program summary 80 hours are necessary to complete the program on all accessible COROT primary targets 16 h have been granted to the program on LUAN and OCA guaranteed time on 2nd semester 2006 (2x4h for differential visibilities / BCD ) and 1st semester 2007 (2x4h for differential phase / HR) The complement has to be claimed on open time and on CNRS- INSU guaranteed time (same period)