MGB and the new Galactic O-Star Spectroscopic Survey spectral classification standard grid

TL;DR

This paper introduces a new spectral classification standard grid for Galactic O stars, a software tool for spectral analysis, and highlights classification errors in a major astronomical database.

Contribution

It presents the first version of MGB software, an improved standard star grid for O star classification, and identifies significant errors in the SIMBAD database.

Findings

MGB software enables spectral type and luminosity class determination.

The new standard grid improves classification accuracy for O stars.

Several misclassified stars in SIMBAD are corrected.

Abstract

In this poster we present three developments related to the Galactic O-Star Spectroscopic Survey (GOSSS). First, we are making public the first version of MGB, an IDL code that allows the user to compare oberved spectra to a grid of spectroscopic standards to measure spectral types, luminosity classes, rotation indexes, and spectral qualifiers. Second, we present the associated grid of standard stars for the spectral types O2 to O9.7, with several improvements over the original GOSSS grid of Sota et al. (2011). Third, we present a list of egregious classification errors in SIMBAD: stars that are or have been listed there as being of O type but that in reality are late-type stars.