A Search for Close Binaries in the ρ Ophiuchi Star-forming Region
Abstract
We have carried out a new, near-infrared speckle imaging survey of 19 members of the young stellar population in the nearby (d=140 pc) ρ Oph cloud core. Results for four binary and one newly discovered triple system are reported. Data for all known multiple systems among the pre-main-sequence population of ρ Oph are tabulated. We define a restricted binary fraction, Fb,r, and a restricted companion fraction, Fc,r, as counting only those systems most detectable in the present and previous high-resolution near-infrared imaging surveys having separations between 0.1" and ~1.1" and K-band magnitude differences ΔK<3. Analysis of all the available multiplicity data results in updated values of Fb,r=24%+/-11% and Fc,r=24%+/-11% for the Ophiuchus pre-main-sequence population. These values are consistent with the values in the Taurus star-forming region, and Fc,r is in excess by a factor of 2 relative to the main sequence at the 1 σ level.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 2003
- DOI:
- 10.1086/375532
- arXiv:
- arXiv:astro-ph/0303595
- Bibcode:
- 2003ApJ...591.1064B
- Keywords:
-
- Stars: Binaries: Close;
- Infrared: Stars;
- Stars: Pre-Main-Sequence;
- Techniques: High Anular Resolution;
- Astrophysics
- E-Print:
- 21 pages, 6 figures, 4 tables