170 likes | 294 Views
Coronagraphic Spectroscopy: Spatially Resolved Spectroscopy with HST STIS. Jessica Donaldson. Circumstellar Disks. Roberge et al. (2005). TW Hydrae. Circumstellar Disks. Roberge et al. (2005). TW Hydrae. Debris Disks. Fainter – target edge-on to get more signal
E N D
Coronagraphic Spectroscopy:Spatially Resolved Spectroscopy with HST STIS Jessica Donaldson
Circumstellar Disks Roberge et al. (2005) TW Hydrae
Circumstellar Disks Roberge et al. (2005) TW Hydrae
Debris Disks • Fainter – target edge-on to get more signal • Targeted 3 bright, edge-on debris disks • HD32297, AU Mic, HR4796A • Is there a change in color with disk radius? • A few debris disks have been targeted with spectrophotometry • HR4796A shows red color in near-IR (Debes et al. 2009) AU Microscopii (Krist et al. 2005)
Coronagraphic Spectroscopy • Scattered light • 52x0.2F2 Aperture • G430L and G750L • Edge-on Debris disk • Slit placed along the length of the disk • Fiducial bar blocks the bright central star
Coronagraphic Spectroscopy Fiducial bar Radius Wavelength
Observations 1) Target – HD32297 PSF reference star 2) Unocculted
Observations 3) Scale and subtract Scattered light from disk only
Observations • Acquisition peak-up • Center star behind the fiducial bar • In wavelength-direction (x-direction) • Contemporaneous lamp flat • For defringing G750L data • Unocculted spectrum • Target and PSF reference star • Occulted spectrum • Target and PSF reference star
Data Reduction • Unsupported mode • We reduced the data ourselves including defringing and wavelength calibration • Started with crj files • Basic data reduction already done including bias and dark subtraction, flat-fielding, and cosmic-ray rejection • Combined multiple orbits before data reduction
Calibration • STSDAS IRAF tasks wavecal, x1d, x2d • Convert flux to cgs units • Correct geometrical distortion
Calibration • STSDAS IRAF tasks wavecal, x1d, x2d • Convert flux to cgs units • Correct geometrical distortion