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We report the detection of flaring events in NGC 4395 ULX1, a nearbyultraluminous X-ray source (ULX), for the first time, using recent XMM-NEWTONobservations. The flaring episodes are spectrally harder than the steadyemission intervals, resulting in higher fractional variability in the highenergy regime. A thin Keplerian and a slim accretion disk provide the best-fitcontinuum for XMM-NEWTON spectra. All observations show a broad hump-likefeature around $\sim 0.9$ keV, which can be associated with a collection ofblended emission lines, and suggests the presence of a wind/outflow in this ULXthrough comparison with other ULXs that show a similar feature. The flaringspectra correspond to higher slim disk temperatures due to higher massaccretion rate under an advection-dominated accretion scenario. Theluminosity-temperature (L-T) values in different flux states show a positivetrend. When characterized with a powerlaw relation, the L-T profile is broadlyconsistent with both $L\propto T^2$ and $L\propto T^4$ relations for theanalysed data. The empirical predictions for a slim accretion disk in the caseof super-Eddington accretion onto a stellar-mass compact object is $L \proptoT^2$ which is a possible scenario in ULX1. The origin of the flaring events isunderstood as an intrinsic change of accretion rate or presence of variableclumpy wind in the inner region of the accretion disk.

Hard X-ray flares and spectral variability in NGC 4395 ULX1