HST-STIS Spatially Resolved Spectroscopy and Coronagraphic Imaging of the TW Hydrae Circumstellar Disk

Abstract

We present the first spatially resolved spectrum of scattered light from the TW Hydrae protoplanetary disk. This nearly face-on disk is optically thick, surrounding a classical T Tauri star in the nearby 10 Myr old TW Hya association. The spectrum was taken with the HST-STIS CCD, providing resolution R ~ 360 over the wavelength range 5250 - 10300 A. Spatially resolved spectroscopy of circumstellar disks is difficult due to the high contrast ratio between the bright star and faint disk. Our novel observations provide optical spectra of scattered light from the disk between 40 AU and 155 AU from the star. The scattered light has the same color as the star (gray scattering) at all radii, except the innermost region. This likely indicates that the scattering dust grains are larger than about 1 micron all the way out to large radii. From the spectroscopic data, we also obtained radial profiles of the integrated disk brightness at two position angles, over almost the same region as previously observed in HST-WFPC2 and NICMOS coronagraphic images (35 AU to 173 AU from the star). The profiles have the same shape as the earlier ones, but show a small azimuthal asymmetry in the disk not previously noted. Our STIS broad-band coronagraphic images of TW Hya confirm the reality of this asymmetry, and show that the disk surface brightness interior to 140 AU has a sinusoidal dependence on azimuthal angle. The maximum brightness occurs at a position angle of 233.6 +/- 5.7 degrees East of North. This might be caused by the combination of forward-scattering and an increase in inclination in the inner region of the disk, suggesting that the TW Hya disk has a warp like that seen in the Beta Pictoris debris disk.

18 pages, 9 figures (some in color). First version submitted to ApJ 2004-08-29, posted to astro-ph 2004-10-10. Revised version accepted for publication in ApJ 2004-12-07, posted to astro-ph 2004-12-08

References in corpus (5)

• Evidence for a developing gap in a 10 Myr old protoplanetary disk
• Imaging the Disk around TW Hya with the Submillimeter Array
• Infrared Views of the TW Hya Disk
• The state of protoplanetary material 10 Myr after stellar formation: circumstellar disks in the TW Hydrae association
• NICMOS Images of the GG Tau Circumbinary Disk

Cited by in corpus (35)

• The TW Hya Disk at 870 microns: Comparison of CO and Dust Radial Structures
• Constraining the X-ray and Cosmic Ray Ionization Chemistry of the TW Hya Protoplanetary Disk: Evidence for a Sub-interstellar Cosmic Ray Rate
• Three radial gaps in the disk of TW Hydrae imaged with SPHERE
• Measuring Turbulence in TW Hya with ALMA: Methods and Limitations
• Towards Planetesimals in the Disk around TW Hya: 3.5 centimeter Dust Emission
• An Inner Hole in the Disk around TW Hydrae Resolved in 7 Millimeter Dust Emission
• Line Emission from Gas in Optically Thick Dust Disks around Young Stars
• CO and dust properties in the TW Hya disk from high-resolution ALMA observations
• Discovery of a Disk Gap Candidate at 20 AU in TW Hydrae
• The anomalously low (sub)millimeter spectral indices of some protoplanetary disks may be explained by dust self-scattering
• On the structure of the transition disk around TW Hya
• The 0.5-2.22-micron Scattered Light Spectrum of the Disk Around TW Hya: Detection of a Partially Filled Disk Gap at 80 AU
• Classical T Tauri stars: magnetic fields, coronae, and star-disc interactions
• Chasing Shadows: Rotation of the Azimuthal Asymmetry in the TW Hya Disk
• Kinematics of the CO Gas in the Inner Regions of the TW Hya Disk
• Observations of Solids in Protoplanetary Disks
• Herschel-PACS observation of the 10 Myr old T Tauri disk TW Hya: Constraining the disk gas mass
• First detection of gas-phase ammonia in a planet-forming disk
• High-resolution Spectroscopy of [Ne II] Emission from TW Hya
• Scattered light shadows in warped protoplanetary discs
• Stringent Limits on the Polarized Submillimeter Emission from Protoplanetary Disks
• ALMA continuum observations of a 30 Myr old gaseous debris disk around HD 21997
• Mapping the Complex Kinematic Substructure in the TW Hya Disk
• Near-infrared imaging polarimetry of dusty young stars
• Formation and evolution of planetary systems: the impact of high angular resolution optical techniques
• Resolved observations of transition disks
• Probing the presence of planets in transition discs' cavities via warps: the case of TW Hya
• The surprising evolution of the shadow on the TW Hya disk
• The inner structure of the TW Hya Disk as revealed in scattered light
• Characteristics of small protoplanetary disc warps in kinematic observations
• Space-Based Coronagraphic Imaging Polarimetry of the TW Hydrae Disk: Shedding New Light on Self-Shadowing Effects
• Optical Coronagraphic Spectroscopy of AU Mic: Evidence of Time Variable Colors?
• Extra-Solar Kuiper Belt Dust Disks
• On the Solar System-Debris Disk Connecction
• Gas and Dust Shadows in the TW Hydrae Disk