A Catalog of Early-type Hα Emission-line Stars and 62 Newly Confirmed Herbig Ae/Be Stars from LAMOST Data Release 7

Abstract

Abstract We derive a catalog of early-type emission-line stars including 30,023 spectra of 25,867 stars from LAMOST Data Release 7, in which 4189 have Simbad records. The spectra are classified into three morphological types (10 subtypes) based on Hα emission-line profiles. Some spectra contaminated by nebula emission lines such as from H ii regions are flagged in the catalog. We also provide a specific catalog of 20 stars with stellar winds or accretion flows by calculating the terminal and peak velocities based on P-Cygni or inverse P-Cygni profiles. More important, with two color–color diagrams, (H-Ks, J-H) and (Ks-W1, H-Ks), of a collection of known Herbig Ae/Be stars (HAeBes) and classical Ae/Be stars (CAeBes), we propose an updated criterion to separate HAeBes from CAeBes. By the criterion, we select 118 HAeBe candidates and 2636 CAeBe candidates from the sample. We confirm 71 of the 118 HAeBes based on the data from LAMOST (optical spectra) and WISE (photometry and images), 62 of which are newly identified. The 71 identified HAeBes are compiled into a specific catalog, and their SEDs and MIR images are also presented. The distances of 76% confirmed HAeBes are further than 1 kpc, which enlarges the number of known HAeBes in further distance. Most of the 71 HAeBes are located in the Galactic disk while 6 of them have ∣Z gal∣ > 400 pc. Four HAeBes show the forbidden emission lines of [Fe ii] and [O i], in which J051425.20+411310.7 is a newly discovered B[e]. In addition, four HAeBes having Spitzer IRS spectra all show PAH features.