AAS 200th meeting, Albuquerque, NM, June 2002
Session 11. Nearby Stars and Low Mass Dwarfs
Display, Monday, June 3, 2002, 9:20am-6:30pm, SW Exhibit Hall

[Previous] | [Session 11] | [Next]

[11.07] Detection of Significant Structure in the Circumstellar Disk of a Pre-Main Sequence Star

C.M. Hamilton (Wesleyan U./Connecticut College), W. Herbst, A. Rhodes (Wesleyan U.), C.A.L. Bailer-Jones, R. Mundt (MPIA), F.J. Vrba (USNO), T. Mazeh (Tel Aviv U.), T. von Hippel (UTexas-Austin), R. Crowe (UHawaii-Hilo), M. Ibrimahov (Maidanak Obs.), K. Haisch (NASA Ames), Z. Webster (UC Berkeley), A. Scholz (Tautenberg)

Photometric and spectroscopic data are presented of KH 15D, a unique, eclipsing pre-main sequence star located in the young (2-4 Myr) cluster NGC 2264. A coordinated international observing campaign took place during the eclipse period from 1-21 December 2001, and involved the following observatories from around the world: Van Vleck, Calar Alto, Maidanak, KPNO, USNO, Wise, UHH, Gemini South, OVRO Millimeter-Wavelength Array, IRTF, and the VLT. This international campaign has allowed us to probe in detail the structure of a disk surrounding a pre-main sequence star for the first time. Preliminary results from these observations indicate that when the object is in eclipse, it appears to be variable at the 0.2 mag level over the course of hours. There is little evidence, however, for variability outside eclipse beyond the 0.03 mag level. No real evidence for a systematic color change between when the object is bright and when it is in eclipse has been observed, indicating that the eclipse must be caused by particles larger than interstellar dust grains. It appears that the favorable geometry in this case is giving us the opportunity to study structure in a disk which has evolved at least part way to the formation of planetesimals. A more complete picture of this object based our multi-wavelength, international campaign is presented.

[Previous] | [Session 11] | [Next]

Bulletin of the American Astronomical Society, 34
© 2002. The American Astronomical Soceity.