A First Look at the X-ray Population of the Young Massive Cluster VVV CL077
arXiv:1501.00496 · doi:10.1088/0004-637X/801/1/49
Abstract
Multi-wavelength analysis of the young massive cluster VVV CL077 is presented for the first time. Our Chandra survey of this region enabled the detection of three X-ray emitting stellar members of the cluster, as well as a possible diffuse X-ray component that extends a few arcseconds from the cluster core with an intrinsic flux of (9+/-3)x10^-14 erg cm^-2 s^-1 in the 0.5-10 keV band. Infrared spectra we obtained for two of these X-ray point sources show absorption lines typical of the atmospheres of massive O stars. The X-ray spectrum from the visible extent of VVV CL077 i.e., a 15"-radius around the cluster, can be modeled with an absorbed power law with nH = (6+/-4)x10^22 cm^-2 and gamma = 2+/-1. In addition, the X-ray core of VVV CL077 coincides with diffuse emission seen in the infrared band and with a local maximum in the radio continuum map. A possible association with a neighboring H II region would place VVV CL077 at a distance of around 11 kpc; on the far side of the Norma Arm. At this distance, the cluster is 0.8 pc wide with a mass density of (1-4)x10^3 Msol pc^-3.
arXiv commentaccepted for publication in The Astrophysical Journal: 9 pages, 5 figures
References in corpus (26)
- On the Absorption of X-rays in the Interstellar Medium
- Young massive star clusters
- A new calibration of stellar parameters of Galactic O stars
- VISTA Variables in the Via Lactea (VVV): The public ESO near-IR variability survey of the Milky Way
- The Relation Between Optical Extinction and Hydrogen Column Density in the Galaxy
- UBVJHK synthetic photometry of Galactic O stars
- On the massive stellar population of the Super Star Cluster Westerlund 1
- A Neutron Star with a Massive Progenitor in Westerlund 1
- The Molonglo Galactic Plane Survey (MGPS-2): Compact Source Catalogue
- An Introduction to the Chandra Carina Complex Project
- New Galactic Star Clusters Discovered in the VVV Survey
- The Slope of the Near Infrared Extinction Law
- Chandra Deep X-ray Observation of a Typical Galactic Plane Region and Near-Infrared Identification
- Diffuse, Non-Thermal X-ray Emission from the Galactic Star Cluster Westerlund 1
- Origin of the Hard X-ray Emission from the Galactic Plane
- The Cluster Wind from Local Massive Star Clusters
- The Integrated Diffuse X-ray Emission of the Carina Nebula Compared to Other Massive Star-forming Regions
- A newly-discovered young massive star cluster at the end of the Galactic Bar
- The Chandra Carina Complex Project: Deciphering the Enigma of Carina's Diffuse X-ray Emission
- Near Infrared Observations of the Giant HII Region W49A: A Starbirth Cluster
- A Rich Population of X-ray Emitting Wolf-Rayet Stars in the Galactic Starburst Cluster Westerlund 1
- Star Cluster Ecology: VII The evolution of young dense star clusters containing primordial binaries
- Two years of monitoring Supergiant Fast X-ray Transients with Swift
- The Norma Arm Region Chandra Survey: X-ray Populations in the Spiral Arms
- Discovery of a young and massive stellar cluster: Spectrophotometric near-infrared study of Masgomas-1
- Near-infrared spectroscopy of 20 new Chandra sources in the Norma Arm