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تسجيل مستخدم جديدUnveiling the Nature of an X-ray flare from 3XMM J014528.9+610729: A candidate spiral galaxy
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Himali Bhatt
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We report an X-ray flare from 3XMM J014528.9+610729, serendipitously detected during the observation of the open star cluster NGC 663. The colour-colour space technique using optical and infrared data reveals the X-ray source as a candidate spiral galaxy. The flare shows fast rise and exponential decay shape with a ratio of the peak and the quiescent count rates of $sim$60 and duration of $sim$5.4 ks. The spectrum during the flaring state is well fitted with a combination of thermal ({sc Apec}) model with a plasma temperature of $rm{1.3pm0.1}$ keV and non-thermal ({sc Power-law}) model with power-law index of $rm{1.9pm0.2}$. However, no firm conclusion can be made for the spectrum during the quiescent state. The temporal behavior, plasma temperature and spectral evolution during flare suggest that the flare from 3XMM J014528.9+610729 can not be associated with tidal disruption events.
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