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Solar-like oscillators and beyond with SIAMOIS Don Kurtz CfA UCLan, UK

Solar-like oscillators and beyond with SIAMOIS Don Kurtz CfA UCLan, UK. Strengths of SIAMOIS. Radial velocities precision: How precise? cm s -1 for solar-like oscillators m s -1 or 10s of m s -1 for other asteroseismic targets At 10s of m s -1 precision there are many targets

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Solar-like oscillators and beyond with SIAMOIS Don Kurtz CfA UCLan, UK

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  1. Solar-like oscillatorsand beyond with SIAMOISDon KurtzCfA UCLan, UK SIAMOIS Kickoff meeting

  2. Strengths of SIAMOIS • Radial velocities precision: How precise? • cm s-1 for solar-like oscillators • m s-1 or 10s of m s-1 for other asteroseismic targets • At 10s of m s-1 precision there are many targets • V=9  10 x the noise of V = 4: OK • v sin i = 100 km s-1  N x the noise of v sin i = 20 km s-1: OK? • S/N is what matters • Big signals can tolerate higher noise SIAMOIS Kickoff meeting

  3. Strengths of SIAMOIS • Dome C – continuous coverage • 80-90% duty cycles • WET (Whole Earth Telescope) costs ~€50,000/week (lower duty cycles) • 20 weeks/year at Dome C = €1,000,000/year SIAMOIS Kickoff meeting

  4. Strengths of SIAMOIS • Dome C – continuous coverage • Continuous coverage by itself leads to new science • High precision is an independent requirement • Some targets don’t need it SIAMOIS Kickoff meeting

  5. An asteroseismic HR Diagram Joergen Christensen-Dalgaard SIAMOIS Kickoff meeting

  6. Probably not YES faint broad-lined (pressure) some bright some sharp-lined For SIAMOIS? Joergen Christensen-Dalgaard SIAMOIS Kickoff meeting

  7. Solar-like oscillators • Are solar-like oscillators good targets for SIAMOIS? • Stochastically driven red giants • Caroline Barban’s talk SIAMOIS Kickoff meeting

  8. Red Giants SIAMOIS Kickoff meeting

  9. Solar-like oscillators • Are solar-like oscillators good targets for SIAMOIS? • Specifically: • Are  Centauri A and B good targets for SIAMOIS? SIAMOIS Kickoff meeting

  10. Bedding, T., et al. 2004, ApJ, 614, 380 Solar-like Oscillations in  Centauri A • UVES & UCLES • 42 oscillation frequencies • ℓ = 1-3 • Mode lifetimes only 1-2 days • Noise level = 2 cm s-1! SIAMOIS Kickoff meeting

  11. Mode lifetimes • Does SIAMOIS beat UVES for short lifetimes? • Some – Josefina Montalban’s talk • Are there solar-like oscillators with longer mode lifetimes? • The Sun! So, of course. • Targets will be found in large numbers before SIAMOIS is operational. • No problem. SIAMOIS Kickoff meeting

  12. Oscillations and planets • Stellar activity, convection and pulsation are “noise” to planet-hunters • Planets are “noise” to asteroseismologists • The two fields are not just complementary • It is mandatory to do both together atcm s-1 precision SIAMOIS Kickoff meeting

  13.  Arae • V = 5.15 • G3IV-V • Prot = 22 days • 14 M planet; Porb = 9.55 days • 43 p-modes detected • 8-day single-site HARPS study Bouchy, F., Bazot, M., Santos, N. C., Vauclair, S., Sosnowska, D., 2005, A&A, 440, 609 SIAMOIS Kickoff meeting

  14.  Arae – the 14 M planet Bouchy, F., Bazot, M., Santos, N. C., Vauclair, S., Sosnowska, D., 2005, A&A, 440, 609 SIAMOIS Kickoff meeting

  15.  Arae – ~8-min the pulsations Bouchy, F., Bazot, M., Santos, N. C., Vauclair, S., Sosnowska, D., 2005, A&A, 440, 609 SIAMOIS Kickoff meeting

  16.  Arae Bouchy, F., Bazot, M., Santos, N. C., Vauclair, S., Sosnowska, D., 2005, A&A, 440, 609 SIAMOIS Kickoff meeting

  17.  Arae and others • 3-week run on SIAMOIS: • Two 9.5-day planet orbits • Excellent asteroseismic frequency resolution • Many more targets with dual payoff will be known by 2010 SIAMOIS Kickoff meeting

  18. Rapidly oscillating Ap (roAp) stars • A stars; H-core burning • Pulsation periods 5 – 21 minutes • Radial velocity amplitudes up to many km s-1 • v sin i < 30 km s-1 • v sin i = 3 m s-1 in  Equ! • Spectrum rich in lines • Good for SIAMOIS SIAMOIS Kickoff meeting

  19. Resolving pulsations in the atmospheresof roAp starswith UVESDon Kurtz, Vladimir Elkin, Gautier Mathys SIAMOIS Kickoff meeting

  20. Atomic diffusion SIAMOIS Kickoff meeting

  21.  = 0.1  = 0.7 Theoretical expectation Saio, 2005, MNRAS, 360, 1022 SIAMOIS Kickoff meeting

  22.  ~ 10-2  ~ 10-5  ~ 10-2  ~ 10-5 SIAMOIS Kickoff meeting

  23. HD 166473 = 1.5 m s-1 SIAMOIS Kickoff meeting

  24. HD 166473 instrumental = 1.3 m s-1 SIAMOIS Kickoff meeting

  25. roAp stars with SIAMOIS • Frequencies will be better-determined than for photometry • You can use the whole spectrum • For example: • HD101065 with HARPS • V = 8; Dec = -46o • Five frequencies with 6 < A < 220 m s-1 • Precision ~ 1 m s-1 Mkrtichian, D., Hatzes, A., 2005, JAA, 26, 185 SIAMOIS Kickoff meeting

  26. What can you do with the frequencies in roAp stars? – HR 1217 SIAMOIS Kickoff meeting

  27. A model and prediction Cunha, M. 1999, PhD thesis, Cambridge Cunha, M. Gough, D., 2001, MNRAS, 319, 1020 Bigot et al. 2000, A&A, 356, 218 SIAMOIS Kickoff meeting

  28. HR 1217photometric campaigns SIAMOIS Kickoff meeting

  29. HR 1217photometric campaigns SIAMOIS Kickoff meeting

  30. SIAMOIS wins • HR 1217 • 5-week WET extended coverage campaign • 46 astronomers • ~€250,000 • duty cycle for 35 days = 36% Kurtz, D. W.; Cameron, C.; Cunha, M. S.; Dolez, N.; Vauclair, G.; Pallier, E.; Ulla, A.; Kepler, S. O.; da Costa, A.; Kanaan, A.; Fraga, L.; Giovannini, O.; Wood, M. A.; Silvestri, N.; Kawaler, S. D.; Riddle, R. L.; Reed, M. D.; Watson, T. K.; Metcalfe, T. S.; Mukadam, A.; Nather, R. E.; Winget, D. E.; Nitta, A.; Kleinman, S. J.; Guzik, J. A.; Bradley, P. A.; Matthews, J. M.; Sekiguchi, K.; Sullivan, D. J.; Sullivan, T.; Shobbrook, R.; Jiang, X.; Birch, P. V.; Ashoka, B. N.; Seetha, S.; Girish, V.; Joshi, S.; Moskalik, P.; Zola, S.; O'Donoghue, D.; Handler, G.; Mueller, M.; Perez, J. M. Gonzalez; Solheim, J.-E.; Johannessen, F.; Bigot, L., 2006, MNRAS, 358, 651 SIAMOIS Kickoff meeting

  31. SIAMOIS wins - aliases SIAMOIS Kickoff meeting

  32. SIAMOIS wins - aliases SIAMOIS Kickoff meeting

  33. SIAMOIS wins - aliases SIAMOIS Kickoff meeting

  34. SIAMOIS wins • SIAMOIS wins because of the duty cycle • A Dome C photometric telescope can compete in this case • Thierry Appourchaux’s talk SIAMOIS Kickoff meeting

  35. roAp star targets for SIAMOIS •  Cir • V = 3.2; Dec = -65o; v sin i < 20 km s-1 • Multi-periodic • Photometry from the ground and from the WIRE satellite cannot quite reach the precision needed. • A (H) = 254  4 m s-1 (UVES) SIAMOIS Kickoff meeting

  36.  Cir Kurtz, D. W.; Sullivan, D. J.; Martinez, P.; Tripe, P. , 1994, MNRAS, 270, 674 SIAMOIS Kickoff meeting

  37.  Cir Matthews, Jaymie M.; Kurtz, D. W.; Martinez, Peter, 1999, ApJ, 511, 422 SIAMOIS Kickoff meeting

  38. roAp star targets for SIAMOIS • HD60435 • V = 8.9 (a bit tough) • Dec = -58o • Prot = 7.679 d; v sin i is low • The most multi-periodic roAp star • A (H) = 495  25 m s-1 (UVES) SIAMOIS Kickoff meeting

  39. HD 60435 Matthews, Jaymie M.; Wehlau, William H.; Kurtz, Donald W. , 1987, ApJ, 313, 782 SIAMOIS Kickoff meeting

  40. HD 60435Asteroseismic signature of helium gradients Vauclair, S.; Théado, S., 2004, A&A, 425, 179 SIAMOIS Kickoff meeting

  41. More targets SIAMOIS Kickoff meeting

  42. More targets -  Scuti stars •  Pup is on the SIAMOIS target list • Solar-like oscillations are predicted in  Scuti stars • Houdek et al. 1999, A&A, 351, 582 • Samadi et al., 2002, A&A, 395, 563 • A ~ 2 m s-1 •  ~ 2 mHz •  Scuti stars are difficult asteroseismically SIAMOIS Kickoff meeting

  43. More targets – PMS  Scuti stars • HR 5999 • V = 7.0 • Dec = -58o • v sin i high (~ 200 km s-1) • The circumstellar nebula should not interfere, as it does in photometry SIAMOIS Kickoff meeting

  44. More targets •  Dor stars • g-mode pulsators • Multiperiodic; P ~ days • Need continuous coverage • Phillipe Mathias’s talk SIAMOIS Kickoff meeting

  45. More targets • RR Lyrae stars – The Blazhko Effect • Blazhko period ~10 – 500 days • Highly non-sinusoidal • many harmonics • Need continuous coverage SIAMOIS Kickoff meeting

  46. More targets - B stars •  Cephei stars: p-mode and g-mode • SPB stars; g-mode • Some are slowly rotating • Some are bright • Even a few frequencies can be scientifically rewarding • B stars have few lines - problem SIAMOIS Kickoff meeting

  47. HD 129929 = V836 Cen 20-yr multicolour photometry Core overshooting with aOV = 0.1 Non-rigid rotation:4 times faster near core V = 8 Dec = -37o Aerts et al., 2003, Science, 300, 926 SIAMOIS Kickoff meeting

  48.  Eridani V = 3.9 Dec = -3o SIAMOIS Kickoff meeting

  49. Continuous coverage - MOST • HD163830 • SPB star • V = 9.3 • B5II/III • 37 days coverage • 20 frequencies detected SIAMOIS Kickoff meeting

  50. HD 163830 Aerts, C.; De Cat, P.; Kuschnig, R.; Matthews, J. M.; Guenther, D. B.; Moffat, A. F. J.; Rucinski, S. M.; Sasselov, D.; Walker, G. A. H.; Weiss, W. W., 2006, ApJ, 642, L65 SIAMOIS Kickoff meeting

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