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Explore surface fields of 1-3 kG in CTTS via Zeeman broadening & maser emissions. Potential field extrapolation & X-ray emission study for LQ Hya & AB Dor fields. Future work with ESPaDOnS for DF Tau & BP Tau magnetospheric accretion models.
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Accretion Channeling in CTTS Scott Gregory, Moira Jardine
Classical T Tauri Stars (CTTS) (Goodson et al. 1997)
Magnetic Field Detection in CTTS • Surface fields of 1-3 kG detected from: • Zeeman broadened spectral lines • (e.g. Johns-Krull et al. 1999). • Circularly polarised lines • Increased line equivalent widths • (e.g. Guenther et al. 1999). • Electron-cyclotron maser emission • (Smith et al. 2003).
Accreting Field Extrapolations • LQ Hya surface map. • Potential field extrapolation with source surface. • Isothermal corona in hydrostatic equilibrium. (Gregory et al. 2004, in preparation)
Accreting Field Extrapolations • AB Dor surface map. • Potential field extrapolation with source surface. • Isothermal corona in hydrostatic equilibrium. (Gregory et al. 2004, in preparation)
Accretion Footpoints Latitude Longitude Latitude Longitude
LQ Hya like field. AB Dor like field. Future Work: X-ray Emission
LQ Hya like field. AB Dor like field. Future Work: X-ray Emission
Future Work • ESPaDOnS(Echelle SpectroPolarimetric Device for the Observation of Stars at CFHT): • Observations of DF Tau and BP Tau (plus V410 Tau and V830 Tau) in 2005. (Petit, Donati & the ESPaDOnS project team 2004) • Magnetospheric accretion models with potential field extrapolations.