Probing the LHS Catalog. I. New Nearby Stars and the Coolest Subdwarf

Abstract

We present moderate resolution spectroscopy of 112 cool dwarf stars to supplement the observations we have already presented in the Palomar/MSU Nearby-Star Spectroscopic Survey. The sample consists of 72 suspected nearby stars added to the The Preliminary Third Catalog of Nearby Stars since 1991 as well as 40 faint red stars selected from the LHS catalog. LHS 1826 is more metal-poor and cooler than the coolest previously known extreme subdwarf, LHS 1742a. LHS 2195 is a very late M dwarf of type M8 V, probably at a distance of ten parsecs. LHS 1937 is an M7 V star at 20 parsecs. Three other previously unobserved LHS stars have estimated distances that place them within 25 parsecs.

15 pages, 1 figure, AASTeX, to appear in the August 1997 PASP

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