Mapping the core of the Tarantula Nebula with VLT-MUSE II. The spectroscopic Hertzsprung-Russell diagram of OB stars in NGC 2070

Abstract

We present the spectroscopic analysis of 333 OB-type stars extracted from VLT-MUSE observations of the central 30 x 30 pc of NGC 2070 in the Tarantula Nebula on the Large Magellanic Cloud, the majority of which are analysed for the the first time. The distribution of stars in the spectroscopic Hertzsprung-Russell diagram (sHRD) shows 281 stars in the main sequence. We find two groups in the main sequence, with estimated ages of 2.1$\pm$0.8 and 6.2$\pm$2 Myr. A subgroup of 52 stars is apparently beyond the main sequence phase, which we consider to be due to emission-type objects and/or significant nebular contamination affecting the analysis. As in previous studies, stellar masses derived from the sHRD are systematically larger than those obtained from the conventional HRD, with the differences being largest for the most massive stars. Additionally, we do not find any trend between the estimated projected rotational velocity and evolution in the sHRD. The projected rotational velocity distribution presents a tail of fast rotators that resembles findings in the wider population of 30 Doradus. We use published spectral types to calibrate the HeI$\lambda$4921/HeII$\lambda$5411 equivalent-width ratio as a classification diagnostic for early-type main sequence stars when the classical blue-visible region is not observed. Our model-atmosphere analyses demonstrate that the resulting calibration is well correlated with effective temperature.

19 pages, 12 figures. Accepted in A&A

References in corpus (29)

• Astrophysics Source Code Library
• Pre-Supernova Evolution of Massive Single and Binary Stars
• An eclipsing binary distance to the Large Magellanic Cloud accurate to 2 per cent
• The R136 star cluster hosts several stars whose individual masses greatly exceed the accepted 150 Msun stellar mass limit
• The role of stellar feedback in the formation of galaxies
• An excess of massive stars in the local 30 Doradus starburst
• The evolution of rotating very massive stars with LMC composition
• The spectroscopic Hertzsprung-Russell diagram
• The spectroscopic Hertzsprung-Russell diagram of Galactic massive stars
• The IACOB project: III. New observational clues to understand macroturbulent broadening in massive O- and B-type stars
• Constraining mixing in massive stars in the Small Magellanic Cloud
• The VLT-FLAMES Tarantula Survey XVI. The optical+NIR extinction laws in 30 Doradus and the photometric determination of the effective temperatures of OB stars
• Testing massive star evolution, star-formation history and feedback at low metallicity : Spectroscopic analysis of OB stars in the SMC Wing
• The VLT-FLAMES Tarantula Survey XIX. B-type Supergiants - Atmospheric parameters and nitrogen abundances to investigate the role of binarity and the width of the main sequence
• The metallicity dependence of envelope inflation in massive stars
• The VLT-FLAMES Tarantula Survey XVIII. Classifications and radial velocities of the B-type stars
• Effects of close binary evolution on the main-sequence morphology of young star clusters
• How stellar rotation shapes the colour magnitude diagram of the massive intermediate-age star cluster NGC 1846
• A census of massive stars in NGC 346. Stellar parameters and rotational velocities
• The young massive SMC cluster NGC 330 seen by MUSE. I. Observations and stellar content
• The IACOB project. VI. On the elusive detection of massive O-type stars close to the ZAMS
• The IACOB project: II. On the scatter of O-dwarf spectral type -- effective temperature calibrations
• First stellar spectroscopy in Leo P
• A study of the effect of rotational mixing on massive stars evolution: surface abundances of Galactic O7-8 giant stars
• BONNSAI: correlated stellar observables in Bayesian methods
• Ongoing star formation at the outskirts of Sextans A: Spectroscopic detection of early-O type stars
• Metallicity dependence of turbulent pressure and macroturbulence in stellar envelopes
• The Puzzling Spectrum of HD 94509
• Resolving stellar populations with integral field spectroscopy

Cited by in corpus (8)

• The R136 star cluster dissected with Hubble Space Telescope/STIS. III. The most massive stars and their clumped winds
• X-ray properties of early-type stars in the Tarantula Nebula from T-ReX
• Classical OBe Stars as Post-Supernova Runaways: Confirming Binary Origins
• A Panchromatic Study of Massive Stars in the Extremely Metal-Poor Local Group Dwarf Galaxy Leo A
• Melnick 33Na: a very massive colliding wind binary system in 30 Doradus
• The Blue supergiant problem and the main-sequence width
• MUSE crowded field 3D spectroscopy in NGC 300 II. Quantitative spectroscopy of BA-type supergiants
• M^3D: Mosaicking M33 with MUSE datacubes I. Unveiling the diversity of HII regions in M33 with MUSE