High contrast and resolution near infrared photometry of the core of R136

Abstract

We present the sharpest and deepest near infrared photometric analysis of the core of R136, a newly formed massive star cluster at the centre of the 30 Doradus star forming region in the Large Magellanic Cloud. We used the extreme adaptive optics of the SPHERE focal instrument implemented on the ESO Very Large Telescope and operated in its IRDIS imaging mode, for the second time with longer exposure time in the H- and K filters. Our aim was to (i) increase the number of resolved sources in the core of R136, and (ii) to compare with the first epoch to classify the properties of the detected common sources between the two epochs. Within the field of view (FOV) of 10.8"x12.1" (2.7pc x3.0pc), we detected 1499 sources in both H and K filters, for which 76% of these sources have visual companions closer than 0.2". The larger number of detected sources, enabled us to better sample the mass function (MF). The MF slopes are estimated at ages of 1, 1.5 and 2 Myr, at different radii, and for different mass ranges. The MF slopes for the mass range of 10-300 solar-mass are about 0.3 dex steeper than the mass range of 3-300 solar-mass, for the whole FOV and different radii. Comparing the JHK colours of 790 sources common in between the two epochs, 67% of detected sources in the outer region (r >3") are not consistent with evolutionary models at 1-2 Myr and with extinctions similar to the average cluster value, suggesting an origin from ongoing star formation within 30 Doradus, unrelated to R136.

24 pages, 20 figures, 6 tables. Accepted for publication in MNRAS

References in corpus (10)

• 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
• Using the minimum spanning tree to trace mass segregation
• The VLT-FLAMES Tarantula Survey XVII. Physical and wind properties of massive stars at the top of the main sequence
• YBC, a stellar bolometric corrections database with variable extinction coefficients: an application to PARSEC isochrones
• The R136 star cluster dissected with Hubble Space Telescope/STIS. II. Physical properties of the most massive stars in R136
• An X-ray Survey of Wolf-Rayet Stars in the Magellanic Clouds. I. The Chandra ACIS Dataset
• The extinction law inside the 30 Doradus nebula
• Search for cool giant exoplanets around young and nearby stars - VLT/NaCo near-infrared phase-coronagraphic and differential imaging
• A Code to Make Your Own Synthetic ObservaTIonS (MYOSOTIS)

Cited by in corpus (9)

• The R136 star cluster dissected with Hubble Space Telescope/STIS. III. The most massive stars and their clumped winds
• Resolving the core of R136 in the optical
• Clues on the presence and segregation of very massive stars in the Sunburst Lyman-continuum cluster at z=2.37
• X-ray properties of early-type stars in the Tarantula Nebula from T-ReX
• Extinction towards the cluster R136 in the Large Magellanic Cloud: An extinction law from the near-infrared to the ultraviolet
• Massive star cluster formation III. Early mass segregation during cluster assembly
• Evolutionary models for the Very Massive Stars in the R136 cluster of 30 Doradus in the Large Magellanic Cloud
• Extreme adaptive optics astrometry of R136. Searching for high proper motion stars
• Lessons learned from SPHERE for the astrometric strategy of the next generation of exoplanet imaging instruments