Ultraviolet Photometry of Stars in the Compact Cluster R136 in the Large Magellanic Cloud

Abstract

view Abstract Citations (25) References (32) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Ultraviolet Photometry of Stars in the Compact Cluster R136 in the Large Magellanic Cloud Hunter, Deidre A. ; Vacca, William D. ; Massey, Philip ; Lynds, Roger ; O'Neil, Earl J. Abstract We present ultraviolet photometry of stars in the Large Magellanic Cloud star cluster R136. The data were obtained with the refurbished Wide Field/Planetary Camera on the Hubble Space Telescope through an ultraviolet filter centered at 1750 Å (F170W). These data, combined with optical HST observations presented previously, are used to explore the hot, luminous stellar population within the cluster. The first question we wanted to address was whether the ultraviolet could place better constraints on differential reddening and the degree of coevality within the cluster than optical photometry alone. The stellar sequence in the color magnitude diagram using the F170W- F555W color is broader than it was in the optical and is broader than would be expected from photometric uncertainties. Although there could be a modest age spread among the massive stars, a large part of the intrinsic spread in the color-magnitude diagram is likely to be due to reddening differences. There is also some evidence that stars in the outer parts of the cluster are affected by a larger range in reddening than those in the smaller region of the cluster core. The second question we addressed is whether ultraviolet photometry in combination with optical photometry can distinguish the most massive stars more readily than is possible with the optical colors. The F170W- F555W color is better at separating B supergiants, of which there is only one in R136, from comparably bright 0 and WoIf-Rayet stars. However, spectral classifications of the stars within R136 will be necessary to properly identify stellar types of the rest of the stars and to disentangle age and reddening effects. Publication: The Astronomical Journal Pub Date: May 1997 DOI: 10.1086/118385 Bibcode: 1997AJ....113.1691H Keywords: MAGELLANIC CLOUDS; GALAXIES: STAR CLUSTERS; GALAXIES: PHOTOMETRY full text sources ADS | data products SIMBAD (14) NED (1) MAST (1) ESA (1) CDS (1)