A radial velocity survey of the Carina Nebula's O-type stars

Abstract

We have obtained multi-epoch observations of 31 O-type stars in the Carina Nebula using the CHIRON spectrograph on the CTIO/SMARTS 1.5-m telescope. We measure their radial velocities to 1--2 km s${}^{-1}$ precision and present new or updated orbital solutions for the binary systems HD 92607, HD 93576, HDE 303312, and HDE 305536. We also compile radial velocities from the literature for 32 additional O-type and evolved massive stars in the region. The combined data set shows a mean heliocentric radial velocity of 0.6 km s${}^{-1}$. We calculate a velocity dispersion of $\le 9.1$ km s${}^{-1}$, consistent with an unbound, substructured OB association. The Tr 14 cluster shows a marginally significant 5 km s${}^{-1}$ radial velocity offset from its neighbor Tr 16, but there are otherwise no correlations between stellar position and velocity. The O-type stars in Cr 228 and the South Pillars region have a lower velocity dispersion than the region as a whole, supporting a model of distributed massive-star formation rather than migration from the central clusters. We compare our stellar velocities to the Carina Nebula's molecular gas and find that Tr 14 shows a close kinematic association with the Northern Cloud. In contrast, Tr 16 has accelerated the Southern Cloud by 10--15 km s${}^{-1}$, possibly triggering further massive-star formation. The expansion of the surrounding H II region is not symmetric about the O-type stars in radial velocity space, indicating that the ionized gas is constrained by denser material on the far side.

arXiv comment20 pages, 16 figures, accepted for publication in MNRAS

References in corpus (88)

• The Gaia mission
• Embedded Clusters in Molecular Clouds
• Binary interaction dominates the evolution of massive stars
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• Mind your Ps and Qs: the Interrelation between Period (P) and Mass-ratio (Q) Distributions of Binary Stars
• A new calibration of stellar parameters of Galactic O stars
• Physical Properties of Wolf-Rayet Stars
• A Computational Guide to Physics of Eclipsing Binaries. Paper I. Demonstrations and Perspectives
• Gaia Data Release 1: Astrometry - one billion positions, two million proper motions and parallaxes
• Southern Massive Stars at High Angular Resolution: Observational Campaign and Companion Detection
• The High Angular Resolution Multiplicity of Massive Stars
• The VLT-FLAMES Tarantula Survey VIII. Multiplicity properties of the O-type star population
• The Galactic O-Star Spectroscopic Survey (GOSSS). II. Bright Southern Stars
• A spectroscopic survey on the multiplicity of high-mass stars
• Non-linear Least Squares Fitting in IDL with MPFIT
• CHIRON - A Fiber Fed Spectrometer for Precise Radial Velocities
• Toward Complete Statistics of Massive Binary Stars: Penultimate Results from the Cygnus OB2 Radial Velocity Survey
• A new library of theoretical stellar spectra with scaled-solar and alpha-enhanced mixtures
• The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables Determined from Cluster Turn-offs. II. Results from 12 Galactic Clusters and OB Associations
• A Census of the Carina Nebula. I: Cumulative Energy Input from Massive Stars
• The Galactic O-Star Spectroscopic Survey (GOSSS). III. 142 additional O-type systems
• An Updated Look at Binary Characteristics of Massive Stars in the Cygnus OB2 Association
• The Tarantula Massive Binary Monitoring: I. Observational campaign and OB-type spectroscopic binaries
• The VLT-FLAMES Tarantula Survey - XI. A census of the hot luminous stars and their feedback in 30 Doradus
• Stellar Rotation in Young Clusters. I. Evolution of Projected Rotational Velocity Distributions
• The Massive Star Population of Cygnus OB2
• Estimating distances from parallaxes. III. Distances of two million stars in the Gaia DR1 catalogue
• A Pan-Carina YSO Catalog: Intermediate-Mass Young Stellar Objects in the Carina Nebula Identified Via Mid-Infrared Excess Emission
• The orbits of open clusters in the Galaxy
• A Radial Velocity Survey of the Cygnus OB2 Association
• Milky Way Kinematics: Measurements at the Subcentral Point of the Fourth Quadrant
• Star formation in unbound giant molecular clouds: the origin of OB associations?
• A Spectroscopic Survey of WNL Stars in the LMC: General Properties and Binary Status
• On the role of the WNH phase in the evolution of very massive stars: Enabling the LBV instability with feedback
• The Mopra Southern Galactic Plane CO Survey
• The VLT-FLAMES Tarantula Survey XIV. The O-Type Stellar Content of 30 Doradus
• Proper motions of the Arches cluster with Keck-LGS Adaptive Optics: the first kinematic mass measurement of the Arches
• High-Mass Cloud Cores in the eta Carinae Giant Molecular Cloud
• Carina OB Stars: X-ray Signatures of Wind Shocks and Magnetic Fields
• HST/ACS H-alpha Imaging of the Carina Nebula: Outflow Activity Traced by Irradiated Herbig-Haro Jets
• A Census of the Carina Nebula -- II. Energy Budget and Global Properties of the Nebulosity
• Cygnus OB2 DANCe: A high precision proper motion study of the Cygnus OB2 association
• X-ray Star Clusters in the Carina Complex
• The catalogue of radial velocity standard stars for Gaia I. Pre-launch release
• Internal dynamics and membership of the NGC 3603 Young Cluster from microarcsecond astrometry
• Distance and the Initial Mass Function of Young Open Clusters In The Eta Carina Nebula: Tr 14 and Tr 16
• The VLT-FLAMES Tarantula Survey. VII. A low velocity dispersion for the young massive cluster R136
• On the velocity dispersion of young star clusters: super-virial or binaries?
• Triggered Star Formation in the LMC4/Constellation III Region of the Large Magellanic Cloud
• Opening the Treasure Chest: A Newborn Star Cluster Emerges from its Dust Pillar in Carina
• The VLT-FLAMES Tarantula Survey. XIII: On the nature of O Vz stars in 30 Doradus
• A VLT/FLAMES survey for massive binaries in Westerlund 1: I. first observations of luminous evolved stars
• Spitzer Space Telescope observations of the Carina Nebula: The steady march of feedback-driven star formation
• A Chandra ACIS Study of the Young Star Cluster Trumpler 15 in Carina and Correlation with Near-infrared Sources
• The Carina Nebula and Gum 31 molecular complex: I. Molecular gas distribution, column densities and dust temperatures
• The first orbital solution for the massive colliding-wind binary HD93162 (=WR25)
• Candidate X-ray-Emitting OB Stars in the Carina Nebula Identified Via Infrared Spectral Energy Distributions
• The Systemic Velocity of Eta Carinae
• Herschel far-infrared observations of the Carina Nebula complex II: The embedded young stellar and protostellar population
• A deep wide-field sub-mm survey of the Carina Nebula complex
• The Giant Pillars of the Carina Nebula
• Optical spectroscopy of X-Mega targets in the Carina Nebula. II. The massive double-lined O-type binary HD 93205
• Radial dependence of line profile variability in seven O9--B0.5 stars
• The star cluster Collinder 232 in the Carina complex and its relation to Trumpler 14/16
• H110alpha recombination-line emission and 4.8-GHz continuum emission in the Carina Nebula
• The deep OB star population in Carina from the VST Photometric H$\alpha$ Survey (VPHAS+)
• Unlocking the Keyhole - H2 and PAH emission from molecular clumps in the Keyhole Nebula
• An investigation of the molecular clouds of the Carina HII region/molecular cloud complex - First results
• Spectral classification and properties of the O Vz stars in the Galactic O-Star Spectroscopic Survey (GOSSS)
• Optical spectroscopy of X-Mega targets in the Carina nebula - VII On the multiplicity of Tr 16-112, HD 93343 and HD 93250
• A Catalog of New Spectroscopically Confirmed Massive OB Stars in Carina
• Gaia-ESO Survey: global properties of clusters Trumpler 14 and 16 in the Carina Nebula
• Optical Spectroscopy of X-Mega targets in the Carina Nebula - VI. FO 15: a new O-Type double-lined eclipsing binary
• Star clusters in the Carina complex: UBVRI photometry of NGC3114, Collinder228 and vdB-Hagen99
• A benchmark for multi-conjugated AO: VLT-MAD observations of the young massive cluster Trumpler 14
• Investigation of the stellar content in the western part of the Carina nebula
• Radial velocities of early-type stars in the Perseus OB2 association
• Optical spectroscopy of X-MEGA targets I. CPD -59 2635: A New Double-Lined O type Binary in the Carina Nebula
• Optical spectroscopy of X-Mega targets in the Carina Nebula - V. The spectroscopic binary HD93161A and its visual companion HD93161B
• A photometric investigation of the young open cluster Trumpler 15
• Extended Red Objects and Stellar Wind Bow Shocks in the Carina Nebula
• Gaia-ESO Survey: Gas dynamics in the Carina Nebula through optical emission lines
• The new Wolf-Rayet binary system WR62a
• WR 148: Identifying the companion of an extreme runaway massive binary
• The Galactic O-Star Spectroscopic Catalog (GOSC) and Survey (GOSSS): first whole-sky results and further updates
• The canonical Luminous Blue Variable AG Car and its neighbor Hen 3-519 are much closer than previously assumed
• Proper motions of five OB stars with candidate dusty bow shocks in the Carina Nebula
• A new massive double-lined spectroscopic binary system: The Wolf-Rayet star WR 68a

Cited by in corpus (13)

• Massive runaways and walkaway stars
• OB associations and their origins
• Combined analysis of neutron star natal kicks using proper motions and parallax measurements for radio pulsars and Be X-ray binaries
• A Gaia view of the two OB associations Cygnus OB2 and Carina OB1: The signature of their formation process
• The young massive star cluster Westerlund 2 observed with MUSE. I. First results on the cluster internal motion from stellar radial velocities
• Carina's Pillars of Destruction: the view from ALMA
• The young massive star cluster Westerlund 2 observed with MUSE. II. MUSEpack -- a Python package to analyze the kinematics of young star clusters
• Stellar Parameters and Radial Velocities of Hot Stars in the Carina Nebula
• The spectroscopic binary fraction of the young stellar cluster M17
• Detection of new O-type stars in the obscured stellar cluster Tr 16-SE in the Carina Nebula with KMOS
• $\eta$ Carinae: high angular resolution continuum, H30$\alpha$ and He30$\alpha$ ALMA images
• Gaia-ESO Survey: massive stars in the Carina Nebula. II. The spectroscopic analysis of the O-star population
• The YMDB catalog: Young massive detached binaries for the determination of high-precision absolute stellar parameters