M dwarf catalog of LAMOST pilot survey

TL;DR

This paper provides a comprehensive spectroscopic catalog of over 67,000 M dwarfs from the LAMOST pilot survey, including spectral types, radial velocities, and activity indicators, facilitating future stellar studies.

Contribution

It introduces a refined classification method, detailed spectral measurements, and a publicly available catalog for M dwarfs from the LAMOST pilot survey, enhancing data accuracy and usability.

Findings

Spectral subtypes were accurately classified using an improved Hammer program.

Radial velocities were precisely measured with an automated cross-correlation method.

Magnetic activity indicators like Hα emission were analyzed for M dwarfs.

Abstract

We present a spectroscopic catalog of 67082 M dwarfs from the LAMOST pilot survey. For each spectrum of the catalog, spectral subtype, radial velocity, equivalent width of H${\alpha}$, a number of prominent molecular band indices and the metal sensitive parameter $\zeta$ are provided . Spectral subtype have been estimated by a remedied Hammer program (Original Hammer: Covey et al. 2007), in which indices are reselected to obtain more accurate auto-classified spectral subtypes. All spectra in this catalog have been visually inspected to confirm the spectral subtypes. Radial velocities have been well measured by our developed program which uses cross-correlation method and estimates uncertainty of radial velocity as well. We also examine the magnetic activity properties of M dwarfs traced by H${\alpha}$ emission line. The molecular band indices included in this catalog are temperature or metallicity sensitive and can be used for future analysis of the physical properties of M dwarfs. The catalog is available on the website \url{http://sciwiki.lamost.org/MCatalogPilot/}.