Verification of Photometric Parallaxes with Gaia DR2 Data

Oleg Malkov,Jayant Murthy,Alexey Sytov,Dmitry Chulkov,Alexey Kniazev,Aleksandr Zhukov,Areg Mickaelian,Dana Kovaleva,Alexey Mironov,Sergey Sichevsky,Olga Dluzhnevskaya,Sergey Karpov,Gang Zhao

doi:10.3390/galaxies7010007

Abstract

Results of comparison of Gaia DR2 parallaxes with data derived from a combined analysis of 2MASS (Two Micron All-Sky Survey), SDSS (Sloan Digital Sky Survey), GALEX (Galaxy Evolution Explorer), and UKIDSS (UKIRT Infrared Deep Sky Survey) surveys in four selected high-latitude | b | > 48° sky areas are presented. It is shown that multicolor photometric data from large modern surveys can be used for parameterization of stars closer than 4400 pc and brighter than g S D S S = 19 . m 6 , including estimation of parallax and interstellar extinction value. However, the stellar luminosity class should be properly determined.

Highlights

One of the main problems of astrophysics is the study of the physical properties belonging to the surface layers of stars
We discuss how including the Gaia parallaxes into the procedure would improve the accuracy of parameterization, and how to select/process objects with unknown
To obtain absolute magnitudes for stars of different spectral types in the corresponding photometric systems Mi, we have compiled a table of absolute magnitudes in 2MASS, SDSS and GALEX surveys using Kraus and Hillenbrand [36], and Findeisen et al [37] data

Summary

Introduction

One of the main problems of astrophysics is the study of the physical properties belonging to the surface layers of stars. Because these stars are observed through interstellar dust, their light is dimmed and reddened, complicating their parameterization and classification. Mironov et al [12] made a critical analysis, compared data for stars included in several atlases, and found many discrepancies. Another way to construct a map of interstellar extinction is its estimation (as well as stellar parameters) from evolutionary tracks. These data were supplanted by the dust maps produced by Schlegel et al [26], who used full sky microwave data made available by the IRAS (Infrared Astronomical Satellite) mission and the DIRBE (Diffuse Infrared Background Experiment) instrument on the COBE

Background

Data and Method

Results and Conclusions