July 31, 2017 to August 3, 2017
Royal Observatory of Belgium
UTC timezone
<br>2nd LAMOST-Kepler workshop<br><br>LAMOST in the era of large spectroscopic surveys<P><img src="https://events.oma.be/indico/event/26/picture/0.jpg" width="466" height="50">

Ages and distances for LAMOST stars with Gaia parallaxes.

Jul 31, 2017, 3:10 PM
Meridian Room (Royal Observatory of Belgium)

Meridian Room

Royal Observatory of Belgium

Av. Circulaire - 3 - Ringlaan 1180 Brussels
Contributed talk 2.1 The LAMOST as a large spectroscopic survey 2.1 The LAMOST as a large spectroscopic survey


Dr Alexey Mints (Max Planck Institute for Solar System Research)


In an effort to unify the spectroscopic data of different surveys for Galactic archaeology purposes we developed and made public our Unified tool for Distance, Age and Mass estimation (UniDAM). This tool is based on a Bayesian method to compute probability density functions of distance modulus, log(age) and mass using spectroscopic parameters (effective temperature, surface gravity and metallicity), infrared photometry (2MASS and AllWISE) and PARSEC isochrones. Here we present the result from UniDAM with Gaia parallaxes incorporated consistently. For over 100,000 LAMOST stars we have Gaia-TGAS parallaxes that we can use to improve distance modulus and log(age) estimates. The use of parallaxes allows us to improve our age and distance estimates substantially - by about 30% in log(age) and about 50% in distance modulus. We also show that further improvements can be expected from further Gaia data releases, bringing log(age) uncertainties to about 0.1 dex and distance modulus uncertainties downto 0.01 mag. We show that for the most distant stars in LAMOST, spectrophotometric estimates of distance modulus will have higher precision even than those from end-of-mission Gaia parallaxes.

Primary author

Dr Alexey Mints (Max Planck Institute for Solar System Research)


Dr Saskia Hekker (Max Planck Institute for Solar System Research)

Presentation materials