Published in

American Astronomical Society, Astronomical Journal, 6(132), p. 2372-2375, 2006

DOI: 10.1086/508514

Links

Tools

Export citation

Search in Google Scholar

Halo Stars near the Hydrogen?burning Limit: The M/L Subdwarf Transition1

Journal article published in 2006 by John E. Gizis ORCID, James Harvin
This paper is made freely available by the publisher.
This paper is made freely available by the publisher.

Full text: Download

Red circle
Preprint: archiving forbidden
Red circle
Postprint: archiving forbidden
Green circle
Published version: archiving allowed
Upload
Policy details
Data provided by SHERPA/RoMEO

Abstract

We present the first far-red spectra of the L subdwarf 2MASS J16262034+3925190 and the late M/early L subdwarf 2MASS J16403197+1231068. We confirm the ultracool subdwarf nature of these objects. 2M1626+3925 shows strong K I absorption, like an L4 dwarf, and is very similar to, but hotter than, the late L subdwarf 2MASS J05325346+8246465. It is unambiguously an L subdwarf. 2M1640+1231 is very similar to SSSPM J1444-2019, which has been classified as sdM9 or early sdL. In contrast to the hotter M subdwarfs, L subdwarfs are characterized by not only enhanced hydrides but also strong TiO. Progress in a classification system requires identification of more subdwarfs to map out their variations.