Multiples among B stars in the Scorpius-Centaurus association
arXiv:2308.09962 · doi:10.1051/0004-6361/202346806
Abstract
We discuss the properties of companions to B stars in the Scorpius-Centaurus association (age ~15 Myr, 181 B-stars). We gathered available data combining high contrast imaging samples with evidence of companions from Gaia, from eclipsing binaries, and from spectroscopy. We evaluated the completeness of the binary search and estimated the mass and semi-major axis for all detected companions. These data provide a complete sample of stellar secondaries for separation >3 au, and they are highly informative as to closer companions. We found evidence for 200 companions around 181 stars. The fraction of single star is 15.2\pm 4.1% for stars with M_A>3.5 Msun while it is 31.5\pm 5.9% for lower-mass stars. The median semi-major axis of the orbits of the companions is smaller for B than in A stars, confirming a turn-over previously found for OB stars. The mass distribution of the very wide (a>1000 au) and closer companions is different. Very few companions of massive stars M_A>5.0 Msun have a mass below solar and even fewer are M stars with a semi-major axis <1000 au. The scarcity of low-mass companions extends throughout the whole sample. Most early B stars are in compact systems with massive secondaries, while lower-mass stars are mainly in wider systems with a larger spread in mass ratios. We interpret our results as the formation of secondaries with a semi-major axis <1000 au (about 80% of the total) by fragmentation of the disk of the primary and selective mass accretion on the secondaries. The observed trends with primary mass may be explained by a more prolonged phase of accretion episodes on the disk and by a more effective inward migration. We detected twelve new stellar companions from the BEAST survey and of a new BD companion at 9.6 arcsec from HIP74752 using Gaia data, and we discuss the cases of possible BD and low-mass stellar companions to HIP59173, HIP62058, and HIP64053.
Accepted on Astronomy and Astrophysics, 31 pages, 24 figures
References in corpus (41)
- Binary interaction dominates the evolution of massive stars
- New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
- The High Angular Resolution Multiplicity of Massive Stars
- The Optical to Mid-Infrared Extinction Law Based on the APOGEE, Gaia DR2, Pan-STARRS1, SDSS, APASS, 2MASS and WISE Surveys
- Stellar Multiplicity and the IMF: Most Stars Are Single
- Toward Complete Statistics of Massive Binary Stars: Penultimate Results from the Cygnus OB2 Radial Velocity Survey
- Hubble Space Telescope NICMOS Observations of T Dwarfs: Brown Dwarf Multiplicity and New Probes of the L/T Transition
- Updated Gaia-2MASS 3D maps of Galactic interstellar dust
- An extraordinary outburst in the massive protostellar system NGC6334I-MM1: quadrupling of the millimeter continuum
- Performance of the VLT Planet Finder SPHERE II. Data analysis and Results for IFS in laboratory
- Binary Stars in the Orion Nebula Cluster
- Visual Binaries in the Orion Nebula Cluster
- On the Distance to the Ophiuchus Star-Forming Region
- The Turbulent Origin of Outflow and Spin Misalignment in Multiple Star Systems
- Age Determination in Upper Scorpius with Eclipsing Binaries
- A rich population of free-floating planets in the Upper Scorpius young stellar association
- Forming spectroscopic massive proto-binaries by disk fragmentation
- Zodiacal Exoplanets in Time (ZEIT) V: A Uniform Search for Transiting Planets in Young Clusters Observed by K2
- Deficit of wide binaries in the eta Chamaeleontis young cluster
- Radial velocities for the Hipparcos-Gaia Hundred-Thousand-Proper-Motion project
- An all-sky sample of intermediate- to high-mass OBA-type eclipsing binaries observed by TESS
- A wide-orbit giant planet in the high-mass b Centauri binary system
- Multiplicity of young stars in and around R Corona Australis
- Chandra spectroscopy of the hot star beta Crucis and the discovery of a pre-main-sequence companion
- The B-type Binaries Characterisation Programme I. Orbital solutions for the 30 Doradus population
- Unveiling the star formation history of the Upper Scorpius association through its kinematics
- The B-Star Exoplanet Abundance Study: a co-moving 16-25 Mjup companion to the young binary system HIP 79098
- BEAST begins: Sample characteristics and survey performance of the B-star Exoplanet Abundance Study
- Testing the companion hypothesis for the origin of the X-ray emission from intermediate-mass main-sequence stars
- A new take on the low-mass brown dwarf companions on wide-orbits in Upper-Scorpius
- What Sets the Radial Locations of Warm Debris Disks?
- Radial velocity measurements of B stars in the Scorpius-Centaurus association
- Lupi: measuring the heartbeat of a doubly-magnetic massive binary with BRITE-Constellation
- HIP 33609 b: An Eccentric Brown Dwarf Transiting a V=7.3 Rapidly Rotating B-Star
- Absolute Parameters of YOung Stars: GG Lup and mu^1 Sco
- Episodic accretion and mergers during growth of massive protostars
- The triple system Zeta Aquarii
- Polarimetric detection of nonradial oscillation modes in the beta Cephei star beta Crucis
- BRITE observations of Centauri and Lupi, the first non-eclipsing members of the new class of nascent binaries
- Automatic algorithm to obtain values via Fourier Transform in BeSOS database
- Three new late-type stellar companions to very dusty WISE debris disks identified with VLT/SPHERE imaging