Lucky Spectroscopy, an equivalent technique to Lucky Imaging. Spatially resolved spectroscopy of massive close visual binaries using the William Herschel Telescope

DOI: 
10.1051/0004-6361/201832885
Publication date: 
01/08/2018
Main author: 
Maíz Apellániz, J.
IAA authors: 
Sota, A.;Alfaro, E. J.
Authors: 
Maíz Apellániz, J.;Barbá, R. H.;Simón-Díaz, S.;Sota, A.;Trigueros Páez, E.;Caballero, J. A.;Alfaro, E. J.
Journal: 
Astronomy and Astrophysics
Publication type: 
Article
Volume: 
615
Pages: 
A161
Abstract: 
Context. Many massive stars have nearby companions whose presence hamper their characterization through spectroscopy. <BR /> Aims: We want to obtain spatially resolved spectroscopy of close massive visual binaries to derive their spectral types. <BR /> Methods: We obtained a large number of short long-slit spectroscopic exposures of five close binaries under good seeing conditions. We selected those with the best characteristics, extracted the spectra using multiple-profile fitting, and combined the results to derive spatially separated spectra. <BR /> Results: We demonstrate the usefulness of Lucky Spectroscopy by presenting the spatially resolved spectra of the components of each system, in two cases with separations of only 0.''3. Those are δ Ori Aa+Ab (resolved in the optical for the first time) and σ Ori AaAb+B (first time ever resolved). We also spatially resolve 15 Mon AaAb+B, ζ Ori AaAb+B (both previously resolved with GOSSS, the Galactic O-Star Spectroscopic Survey), and η Ori AaAb+B, a system with two spectroscopic B+B binaries and a fifth visual component. The systems have in common that they are composed of an inner pair of slow rotators orbited by one or more fast rotators, a characteristic that could have consequences for the theories of massive star formation.
Database: 
ADS
SCOPUS
URL: 
https://ui.adsabs.harvard.edu/#abs/2018A&A...615A.161M/abstract
ADS Bibcode: 
2018A&A...615A.161M
Keywords: 
binaries: spectroscopic;binaries: visual;methods: data analysis;stars: early-type;stars: massive;techniques: spectroscopic;Astrophysics - Solar and Stellar Astrophysics;Astrophysics - Instrumentation and Methods for Astrophysics