High-resolution spectroscopic study of massive blue and red supergiants in Per OB1. (arXiv:2008.13299v2 [astro-ph.SR] UPDATED)
<a href="http://arxiv.org/find/astro-ph/1/au:+Burgos_A/0/1/0/all/0/1">A. de Burgos</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Simon_Diaz_S/0/1/0/all/0/1">S. Simón-Díaz</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lennon_D/0/1/0/all/0/1">D. J. Lennon</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dorda_R/0/1/0/all/0/1">R. Dorda</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Negueruela_I/0/1/0/all/0/1">I. Negueruela</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Urbaneja_M/0/1/0/all/0/1">M. A. Urbaneja</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Patrick_L/0/1/0/all/0/1">L. R. Patrick</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Herrero_A/0/1/0/all/0/1">A. Herrero</a>
The Perseus OB1 association hosts one of the most populous groupings of blue
and red supergiants (Sgs) in the Galaxy. We discuss whether the massive O-type
and blue/red Sg stars located in the Per OB1 region are members of the same
population and examine their binary and runaway status. We gathered a total of
405 high-resolution spectra for 88 suitable candidates around 4.5 deg from the
center of the association, and compiled Gaia DR2 astrometry for all of them.
This was used to investigate membership and identify runaway stars. By
obtaining high-precision radial velocity (RV) estimates, we investigated the RV
distributions of sample and identified spectroscopic binaries (SBs). Most of
the investigated stars belong to a physically linked population located at d =
2.5$pm$0.4 kpc. We identify 79 confirmed or likely members, and 5 member
candidates. No important differences are detected in the distribution of
parallaxes for stars in h and X Persei or the full sample. On the contrary,
most O-type stars seem to be part of a differentiated population in terms of
kinematical properties. In particular, the percentage of runaways among them
(45%) is considerable higher than for the more evolved targets (that is below
5% in all cases). A similar tendency is also found for the percentage of
clearly detected SBs, which already decreases from 15% to 10% when comparing
the O star and B Sg samples, respectively, and practically vanishes in the
cooler Sgs. All but 4 stars in our working sample can be considered as part of
the same (interrelated) population. However, any further attempt to describe
the empirical properties of this sample of massive stars in an evolutionary
context must take into account that an important fraction of the O stars is –
or has likely been – part of a binary/multiple system. In addition, some of the
other more evolved targets may have also been affected by binary evolution.
The Perseus OB1 association hosts one of the most populous groupings of blue
and red supergiants (Sgs) in the Galaxy. We discuss whether the massive O-type
and blue/red Sg stars located in the Per OB1 region are members of the same
population and examine their binary and runaway status. We gathered a total of
405 high-resolution spectra for 88 suitable candidates around 4.5 deg from the
center of the association, and compiled Gaia DR2 astrometry for all of them.
This was used to investigate membership and identify runaway stars. By
obtaining high-precision radial velocity (RV) estimates, we investigated the RV
distributions of sample and identified spectroscopic binaries (SBs). Most of
the investigated stars belong to a physically linked population located at d =
2.5$pm$0.4 kpc. We identify 79 confirmed or likely members, and 5 member
candidates. No important differences are detected in the distribution of
parallaxes for stars in h and X Persei or the full sample. On the contrary,
most O-type stars seem to be part of a differentiated population in terms of
kinematical properties. In particular, the percentage of runaways among them
(45%) is considerable higher than for the more evolved targets (that is below
5% in all cases). A similar tendency is also found for the percentage of
clearly detected SBs, which already decreases from 15% to 10% when comparing
the O star and B Sg samples, respectively, and practically vanishes in the
cooler Sgs. All but 4 stars in our working sample can be considered as part of
the same (interrelated) population. However, any further attempt to describe
the empirical properties of this sample of massive stars in an evolutionary
context must take into account that an important fraction of the O stars is –
or has likely been – part of a binary/multiple system. In addition, some of the
other more evolved targets may have also been affected by binary evolution.
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