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We report our findings on a new quasi-periodic oscillation (QPO) and a longperiod from the ultraluminous X-ray source (ULX) X-2 in nearby galaxy NGC 4736based on the Chandra and XMM-Newton archival data. To examine the timingproperties, power density spectra of the source have been obtained using FastFourier Transform. Also the spectral parameters of the source have beencalculated by obtaining and fitting the energy spectra. Power density spectrumof this source reveals a QPO peak at $0.73_{-0.14}^{+0.16}$ mHz with anfractional rms variability of 16% using the Chandra data (in the year2000-lower state of the source). The XMM-Newton data analysis indicates a peakat $0.53_{-0.35}^{+0.09}$ mHz with a fractional rms variation of 5% (in theyear 2006-higher state of the source). These recovered QPOs overlap withinerrors and may be the same oscillation. In addition, we detect a longperiodicity or a QPO in the Chandra data of about $(5.2\pm2.0)\times10^{-5}$ Hz($\sim$ 5.4 hrs) over 3 $\sigma$ confidence level. If this is a QPO, it is thelowest QPO detected from a ULX. The mass of the compact object in ULX X-2 isestimated using the Eddington luminosity and a disk blackbody model in therange (10$-$80) M_{\sun}.

A search for periodicities from a ULX in the LINER galaxy NGC 4736