A Diffraction-Limited Keck Multiplicity Survey of the Lowest Mass T Tauri Stars in Taurus-Auriga: Evidence for a Separation Dependent Mass Ratio Distribution

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We present the results of a speckle imaging K[2.2 micron]-band survey conducted with the W. M. Keck 10-m telescope of 44 of the lowest mass T Tauri stars in Taurus-Auriga. Twenty-three companion stars are identified with separations ranging from 0."027 to 7."2 and magnitude differences of up to 5.5; 17 of these are new detections. All companions should have been detected over the angular separation range of 0."05 to 2."6 (7 - 360 AU) and the magnitude difference range of 0.0 to 2.75. Within this region, the companion star fraction is 0.27 +- 0.08, which is somebut lower but statistically comparable to that found in surveys that focused on the somewhat more massive (approx. solar mass) stars 0.45 +- 07. An analysis of the magnitude difference distribution, which is a proxy of mass ratio, as a function of separation suggests that there is a separation dependence. Splitting the sample of binary stars in half (at approx. 20 AU), we find that the closer pairs have a much higher fraction of equal mass systems. These results are consistent with models of binary star formation based on fragmentation followed by accretion. Follow-up observations have measured the orbital motion of the closest binary star pairs. Continued monitoring over the next few years should provide exact total masses for these systems, some of which appear to be sub-stellar, and will thereby add important additional constraints for the wide array of existing evolutionary models, which are particularly uncertain towards lower masses. This work was supported a grant number NAG-6975 from NASA's Origins of Solar Systems program.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

A Diffraction-Limited Keck Multiplicity Survey of the Lowest Mass T Tauri Stars in Taurus-Auriga: Evidence for a Separation Dependent Mass Ratio Distribution does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A Diffraction-Limited Keck Multiplicity Survey of the Lowest Mass T Tauri Stars in Taurus-Auriga: Evidence for a Separation Dependent Mass Ratio Distribution, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Diffraction-Limited Keck Multiplicity Survey of the Lowest Mass T Tauri Stars in Taurus-Auriga: Evidence for a Separation Dependent Mass Ratio Distribution will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1269383

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.