Active Luminous Blue Variables in the Large Magellanic Cloud

WALBORN, N. R.; GAMEN, R. C.; MORRELL, N. I.; BARBÁ, R. H.; FERNÁNDEZ-LAJÚS, E.; ANGELONI, R.

The Astronomical Journal

IOP

Año: 2017 vol. 154 p. 15 - 41

We present extensive spectroscopic and photometric monitoring of twofamous and currently highly active luminous blue variables (LBVs) in theLarge Magellanic Cloud (LMC), together with more limited coverage ofthree further, lesser known members of the class. R127 was discovered asan Ofpe/WN9 star in the 1970s but entered a classical LBV outburst in orabout 1980 that is still in progress, thus enlightening us about theminimum state of such objects. R71 is currently the most luminous starin the LMC and continues to provide surprises, such as the appearance of[Ca ii] emission lines, as its spectral type becomes unprecedentedlylate. Most recently, R71 has developed inverse P Cyg profiles in manymetal lines. The other objects are as follows: HDE 269582, now a?second R127? that has been followed from Ofpe/WN9 to A typein its current outburst; HDE 269216, which changed from late B in 2014to AF in 2016, its first observed outburst; and R143 in the 30 Doradusoutskirts. The light curves and spectroscopic transformations arecorrelated in remarkable detail and their extreme reproducibility isemphasized, both for a given object and among all of them. It is nowbelieved that some LBVs proceed directly to core collapse. One of theseunstable LMC objects may thus oblige in the near future, teaching useven more about the final stages of massive stellar evolution.