Is NGC 470 HLX1 a pulsar?

We propose to study one known hyperluminous X-ray source, NGC 470 HLX1,simultaneously with XMM and NuSTAR for the first time. Archival soft X-raydata suggest that the source exhibits a hard pulsator like spectra andshows a marginal hint of pulsed signal. This motivates us to detect thepulsation in the new high S/N data with high confidence and study itsbroadband spectral properties to understand its underlying accretionmechanism which was previously not possible due to unavailability ofbroadband X-ray data. Pulsar population in HLXs are rare, hence, ifthe detection of pulsation emerge to be a real signal, NGC 470 HLX1will be the second HLX pulsar. Therefore we propose to coordinate asimultaneous observation with 70 ksec XMM and 120 ksec NuSTAR exposurefor NGC 470 HLX1.