The Nearest and Coolest L dwarfs---how near and how cool?

Computer Science

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

Using 2MASS data, we have completed the first systematic, all-sky survey for ultracool dwarfs within 20 parsecs of the Sun. With follow- up observations of 95% of our candidates, we have identified 100 new nearby late-M and L dwarfs, tripling the local census. In this proposal, we aim to complete observations of the final 40 of the 44 remaining candidates and, at a lower priority, to get optical spectra of nine nearby L dwarfs identified with NIR (6 objects) and low signal-to- noise optical (3 objects) data. Spectral types provide the most reliable distance estimates (σ_d ~ +/- 15%) for L dwarfs, but it is crucial that those types are derived from optical spectra. Experience has shown that near-infrared classifications often differ by 2 to 3 spectral classes from the optical benchmarks, corresponding to (Delta) M_J=1 to 1.5 magnitudes, or (delta) d ~ 60-100%. Systematic errors of this magnitude obviously result in substantial uncertainties in derived space densities. We therefore propose to finalize our luminosity function analysis by obtaining red spectra of 49 candidates with two nights on the Blanco 4m RC Spectrograph (22 targets, 13< J< 15), 24 hours with GMOS on Gemini South (24 targets, J> 15, (delta)< -3), and 3 hours with GMOS on Gemini North (3 targets, J> 15, (delta)> +15). This sample is likely to include the coolest, lowest- luminosity L dwarfs in the immediate Solar Neighborhood.

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

The Nearest and Coolest L dwarfs---how near and how cool? 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 The Nearest and Coolest L dwarfs---how near and how cool?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Nearest and Coolest L dwarfs---how near and how cool? will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-796946

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