ar X iv : a st ro - p h / 05 01 32 2 v 1 1 6 Ja n 20 05 Multiple Outbursts of a Cataclysmic Variable in the Globular Cluster M 22
نویسندگان
چکیده
We present a 4 year light curve of a cataclysmic variable in M22, based on an analysis of accumulated data from the MOA microlensing survey. The position of the star coincides with that of a transient event observed by HST in 1999, originally attributed to microlensing but later suspected to be a dwarf nova outburst. Two outburst episodes, one in 2002 and one in 2003, with ∆I ∼ 3 are seen in the MOA data thus confirming that the HST event was a dwarf nova outburst. The MOA and HST data show that this dwarf nova underwent at least three outburst episodes during 1999–2004. Further close monitoring of this event is encouraged as future outburst episodes are expected. Subject headings: globular clusters: individual(M 22) — stars: dwarf novae — gravitational lensing — techniques: image processing
منابع مشابه
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