A sample of galaxy pairs identified from the LAMOST spectral survey and the Sloan Digital Sky Survey

TL;DR

This paper presents a new sample of 1,102 galaxy pairs identified through combined LAMOST and SDSS data, enhancing the study of galaxy interactions by including galaxies missed due to fiber collision effects.

Contribution

It introduces a complementary galaxy sample from LAMOST, and identifies galaxy pairs that supplement SDSS data, reducing bias in galaxy interaction studies.

Findings

Sample of 1,102 galaxy pairs identified

Pairs include galaxies missed by SDSS due to fiber collision

Enhanced dataset for studying galaxy interactions and merging

Abstract

A small fraction($<10\%$) of SDSS main sample galaxies(MGs) have not been targeted with spectroscopy due to the the fiber collision effect. These galaxies have been compiled into the input catalog of the LAMOST extra-galactic survey and named as the complementary galaxy sample. In this paper, we introduce the project and the status of the spectroscopies of the complementary galaxies in the first two years of the LAMOST spectral survey(till Sep. of 2014). Moreover, we present a sample of 1,102 galaxy pairs identified from the LAMOST complementary galaxies and SDSS MGs, which are defined as that the two members have a projected distance smaller than 100 kpc and the recessional velocity difference smaller than 500 $\rm kms^{-1}$. Compared with the SDSS only selected galaxy pairs, the LAMOST-SDSS pairs take the advantages of not being biased toward large separations and therefor play as a useful supplement to the statistical studies of galaxy interaction and galaxy merging.