VELOCITY STRUCTURE AND VARIABILITY OF [O III] EMISSION IN BLACK HOLE HOST GLOBULAR CLUSTER RZ2109

We present a multi-facility study of the optical spectrum of the extragalactic globular cluster RZ2109, which hosts a bright black hole X-ray source. The optical spectrum of RZ2109 shows strong and very broad [O III] {lambda}{lambda}4959, 5007 emission in addition to the stellar absorption lines typical of a globular cluster. We use observations over an extended period of time to constrain the variability of these [O III] emission lines. We find that the equivalent width of the lines is similar in all of the data sets; the change in L[O III] {lambda}5007 is {approx}