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IAC science with the prototype SONG node at Tenerife Katrien Uytterhoeven research group ‘Solar and Stellar Seismology and Extrasolar planet searches’ (7 staff, 2 PostDocs, 3 PhD) Seismology Interests in SONG: * the Sun-as-a-star * solar-like stars * red giants * SdB stars * δ Sct, γ Dor * β Cep, SPB * OB supergiants * binaries with pulsating components planets * follow-up of planet candidates Massive main-sequence pulsators = γ Dor, δ Sct, SPB, β Cep Seismic study requires identified (l,m) modes! Problem: mode-ID does not rely on regularity of frequency spectrum δ Sct HD50844 Mode-ID via line-profile analysis! (l,m) * amplitude and phase distribution across line-profile * velocity moments GOAL: SONG RV time-series a) mode-identification! b) test and improve seismic models Sun-as-a-star: SONG and Mark-I Mark-I * operational at Obs. Teide since 1976 * full-time monitoring since 1984 * RV of the Sun through potassium KI 769.9 nm line * sampling rate: 2sec GOAL: daytime solar spectra with SONG a) compare simultaneous (same site!) Mark-I and SONG observations (resample to same sampling rate) b) evaluate quality and sensitivity of SONG solar observations Planet transits Use SONG photometry to confirm transit candidates through color changes during transit See talk by Brandon! > 50 staff scientists > 65 post-docs > 35 PhD students Interests in SONG from IAC research groups other than the group on ‘Solar and Stellar Seismology and Extrasolar planet searches’ i. Wavelength variations in Solar spectral lines twilight sky spectrum HET McDonald observatory * 1 yr solar orbit ampl=0.507 km s-1 * 1 d Earth orbit (not well covered) + other deviations! ΔT = 1750 days Origin of deviations? * changes in granulation properties along solar cycle * presence of planets e.g. Jupiter: 13 m s-1 over 12yr GOAL: twilight sky spectra with SONG and I2 cell a) investigate wavelength stability of the solar spectrum b) demonstrate that deviations due to a Jupiter-size planet can unambigously be found c) study stellar activity ii. Low mass X-ray binaries Rémon Cornelisse * Compact Binaries (Porb~hrs), primary is compact object (neutron star, black hole). * Roche-lobe overflow, matter accreted via accretion disk. * Inner accretion disk gives rise to X-rays. * optical emission due to Reprocessing of Xrays in outer accretion disk * Different optical wavelengths probe different parts of the outer accretion disk Large night to night changes in lightcurve morphology Origin? changes in accretion disk due to precession or the presence of a warp? Goal: ~1 week continuous multi-colour photometric monitoring with the SONG network a) understand the origin of the lightcurve changes b) understand physics of the accretion disk iii. Classical Novae at maximum light Alessandro Ederoclite Nova = thermonuclear explosions on surface of white dwarf accreting mass in a close binary * brightening (< V=10mag few weeks) T Pyx, lightcurve * FeII or He/N line absorption Mag * mysterious absorption systems (THEA) questions: * origin of absorption lines? * model that fits at all wavelengths ? MJD - 2450000 T Pyx, FIES spectra 15.04.2011 GOAL: few SONG spectra per day (without I2 cell) during max light of novae follow-up optical thick and thin phase Time a) describe chemistry b) describe dynamics of explosion 30.05.2011 iv. Chemical analysis of EBs Carlos Allende Prieto Well-detached EBs are best calibrators for models of stellar structure and evolution accurate orbital parameters, M*, R* ! BUT! spectral chemical analysis is lacking! GOAL: SONG spectra (without I2 cell) of well-known, bright, well-detached EBs at max separation a) derive metallicity and chemical abundances of binary components b) calibrate models stellar structure & evolution v. Multiple populations in globular clusters Antonino Milone Many globular clusters show multiple sequences! GOAL: SONG spectra of bright stars in GCs (filling program) derive chemical and dynamical properties and try to solve: a)abundance anomalies b) multiple sequences c)horizontal branch morphology CMD of NGC 2808 with isochrones vi. macroturbulent broadening in OB supergiants Sergio Simón Díaz OB SGs show extra line broadening: ‘macrotubulence’ origin? pilot study! signature of collective effect of pulsations?! GOAL: time-series of SONG spectra of bright OB supergiants a) understand ‘macroturbulence’ b) improve atmosphere models of OB SGs c) first seismic studies of OB SGs! promising! IAC science many interesting filling programs and additional SONG science programs for SONG-OT!