Tight LMC massive star clusters R 127 and R 128 ?
نویسنده
چکیده
We study the Large Magellanic Cloud (LMC) star clusters R 127 and R128 using imaging and spectroscopy obtained at the ESO NTT telescope. An advanced image restoration technique allows us to resolve these two clusters into at least 14 and 33 stars respectively and obtain their photometry. In particular, we show that the core of R 127 is composed of at least four stars and identify the Luminous Blue Variable (LBV) component. The closest neighbor of the LBV (star #8) is 1′′ .5 away. Moreover, from medium dispersion spectroscopy we determine the spectral types for 19 stars in and near both clusters, and in particular present the first spatially resolved observation of the second brightest component of the R127 cluster (star #3) situated 3′′ .3 from the LBV. By comparing with evolutionary models we also look into the stellar ages. The oldest stars of the cluster are ∼ 6–8 Myr old, whereas the most massive star of the region (#7), formed ∼ 3 Myr ago as an 80M star, has turned into an LBV, the “R 127” star.
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تاریخ انتشار 2003