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We present a new spectroscopic orbit of the O-type binary system HD 152147. We identify absorption lines in both components and use their radial velocities to determine the orbit, which results in a period of P = 50.2199 ± 0.0007 d, an eccentricity e = 0.738 ± 0.007, and a mean separation between the components of asin i = 151 ± 1 R⊙. Considering that the distance to the system is 1600 pc, this implies an angular separation of ∼0.44 mas, making it suitable for modern interferometric observations. In addition, we determine the fundamental stellar parameters of each component by means of a quantitative spectral analysis. We obtain Ma = 31.9−34.6 M⊙ and Ra = 17−24 R⊙ for the primary, and Mb = 14−15 M⊙ and Rb = 5−10 R⊙ for the secondary. We apply models with rotation to try to characterize the evolutionary status of the HD 152147 system. We find that the two components are compatible with a common age of 4.5 Myr. We also detect variations in the profile of Hα that are not modulated by the orbital cycle. Moreover, TESS photometry also presents intrinsic variability and was analysed for periodicities. We find a most relevant frequency of 20 times the orbital one, in a TESS data set that includes the periastron passage, and we interpret it as a tidally induced pulsation that seems to dissipate on a time-scale shorter than the orbital cycle because it is not present in another TESS data set that nearly covers the apoastron.

Multiplicity is a ubiquitous characteristic of massive stars. Multiple systems offer us a unique observational constraint on the formation of high-mass systems. Herschel 36 A is a massive triple system composed of a close binary (Ab1-Ab2) and an outer component (Aa). We measured the orbital motion of the outer component of Herschel 36 A using infrared interferometry with the AMBER and PIONIER instruments of ESO’s Very Large Telescope Interferometer. Our immediate aims are to constrain the masses of all components of this system and to determine if the outer orbit is co-planar with the inner one. Reported spectroscopic data for all two components of this system and our interferometric data allow us to derive full orbital solutions for the outer orbit Aa-Ab and the inner orbit Ab1-Ab2. For the first time, we derive the absolute masses of mAa = 22.3 ± 1.7, mAb1 = 20.5 ± 1.5, and mAb2 = 12.5 ± 0.9 M⊙. Despite not being able to resolve the close binary components, we infer the inclination of their orbit by imposing the same parallax as the outer orbit. Inclinations derived from the inner and outer orbits imply a modest difference of about 22° between the orbital planes. We discuss this result and the formation of Herschel 36 A in the context of Core Accretion and Competitive Accretion models, which make different predictions regarding the statistic of the relative orbital inclinations. © 2022 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society., RS and AA acknowledge financial support from the State Agency for Research of the Spanish MCIU through the ‘Center of Excellence Severo Ochoa’ award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709). RS acknowledges financial support from national project PGC2018-095049-B-C21 (MCIU/AEI/FEDER, UE). AA acknowledges financial support from national project PID2020-117404GB-C21 (MCIU/AEI/FEDER, UE). JSB acknowledges the financial support from the ‘Visitor Scientist Program’ of the ‘Center of Excellence Severo Ochoa’ provided by the IAA-CSIC; and to the ‘ESO-Garching Visitor Program’ of the European Southern Observatory. This work presents results from the European Space Agency (ESA) space mission Gaia. Gaia data are being processed by the Gaia Data Processing and Analysis Consortium (DPAC). Funding for the DPAC is provided by national institutions, in particular the institutions participating in the Gaia MultiLateral Agreement (MLA).

Stellar rotation is of key importance for the formation process, evolution, and final fate of massive stars. In this paper we review results from the study of the spin rate properties of a sample of more than 400 Galactic O-type stars surveyed by the IACOB and OWN projects. By combining vsini, Teff, and logg estimates (resulting from a detailed quantitative spectroscopic analysis) with information about the spectroscopic binarity status for an important fraction of the stars in the sample, we provide a renewed overview about how the empirical distribution of projected rotational velocities in the O-star domain depends on mass, evolutionary and binary status. The obtained distributions are then compared with predictions of several state-of-the-art evolutionary models for single stars, as well as from population synthesis simulations including binary interaction, and used to provide hints about the initial velocity distribution of stars with masses in the range ~15-80 Msol., Comment: 24 pages, 19 figures, accepted for publication in Astronomy & Astrophysics

This article is an erratum for Astronomy and Astrophysics 626: A20 (2019).-- http://hdl.handle.net/10261/201335, No abstract