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We report the first detection of a Fe K$_{\alpha}$ line and soft X-ray lag inthe ultraluminous X-ray source (ULX) NGC 7456 ULX-1. The XMM-Newton spectrashow the presence of the 6.4 keV Fe line at 2.6$\sigma$ confidence and an upperlimit on the FWHM of 32900 km s$^{-1}$. Assuming that the line arises byreflection from a Keplerian disk, it must originate beyond $85 r_{\rm g}$ fromthe compact object. As a result of Fourier timing analysis we found that thesoft X-ray photons lag behind the hard X-ray photons with a $\sim$1300 s delay.The covariance spectra indicate that the hard spectral component is responsiblefor the correlated variability and the soft X-ray lag. This is the second ULXin which a Fe K$_{\alpha}$ line is found, the fifth with a soft X-ray lag, andthe first with both features detected.

Evidence for Fe K$_{\alpha}$ line and soft X-ray lag in NGC 7456 ULX-1