A Circumstellar Disk in a Pre-main-sequence Binary Star

New high-resolution images of HK T Tauri B, the companion to the 106 yr old classical T Tauri star HK Tauri A, show it to be surrounded by an optically thick, edge-on circumstellar disk that extends to a radius of at least 50 AU. The images were taken using a modified speckle technique to achieve a linear resolution of 8 AU. The disk is strikingly coherent, showing no evidence of any strong perturbation by the primary star. The disk is illuminated by the central star, and it hides the star from direct view. The small changes in vertical thickness with wavelength require a dust + gas mass 10-3 M☉. The relative position angles of the disk and the binary suggest that the disk probably does not lie in the plane of the binary orbit.

[1]  P. Goldreich,et al.  Spectral Energy Distributions of T Tauri Stars with Passive Circumstellar Disks , 1997, astro-ph/9706042.

[2]  L. Hartmann,et al.  Model scattering envelopes of young stellar objects. I - Method and application to circumstellar disks , 1992 .

[3]  B. T. Soifer,et al.  The Near Infrared Camera on the W. M. Keck Telescope , 1994 .

[4]  G. Fuller,et al.  Submillimeter photometry and disk masses of T Tauri disk systems , 1990 .

[5]  John E. Krist,et al.  An Edge-on Circumstellar Disk in the Young Binary System HK Tauri , 1998 .

[6]  Mark J. McCaughrean,et al.  Direct Imaging of Circumstellar Disks in the Orion Nebula , 1996 .

[7]  J. Papaloizou,et al.  On the dynamics of tilted discs around young stars , 1995 .

[8]  Martin G. Cohen,et al.  Observational studies of pre-main-sequence evolution. , 1979 .

[9]  Masato Ishiguro,et al.  Discovery of a Rotating Protoplanetary Gas Disk around the Young Star GG Tauri , 1993 .

[10]  G. Neugebauer,et al.  THE FIRST DIFFRACTION-LIMITED IMAGES FROM THE W. M. KECK TELESCOPE , 1996 .

[11]  Ian S. McLean.  Infrared astronomy with arrays : the next generation , 1994 .

[12]  Z. Wen,et al.  Postrefurbishment mission Hubble Space Telescope images of the core of the Orion Nebula: Proplyds, Herbig-Haro objects, and measurements of a circumstellar disk , 1994 .

[13]  Alan M. Watson,et al.  Hubble Space Telescope Observations of the Disk and Jet of HH 30 , 1996 .

[14]  C. Clarke,et al.  The role of discs in the formation of binary and multiple star systems , 1991 .

[15]  H. Martel,et al.  Fragmentation of elongated cylindrical clouds. IV - Clouds with solid-body rotation about an arbitrary axis , 1992 .

[16]  Kevin T. C. Jim,et al.  Adaptive Optics Imaging of GG Tauri: Optical Detection of the Circumbinary Ring , 1996 .

[17]  S. Beckwith,et al.  Millimeter-wave continuum measurements of young stars , 1995 .

[18]  OPTICAL AND NEAR-INFRARED MODEL IMAGES OF THE CIRCUMSTELLAR ENVIRONMENTS OF CLASSICAL T TAURI STARS , 1998 .

[19]  S. Beckwith,et al.  A Survey for Circumstellar Disks around Young Stellar Objects , 1990 .

[20]  S. Lubow,et al.  Dynamics of binary-disk interaction. 1: Resonances and disk gap sizes , 1994 .

[21]  Steven V. W. Beckwith,et al.  Particle Emissivity in Circumstellar Disks , 1991 .