EXPLORATORY CHANDRA OBSERVATION of the ULTRALUMINOUS QUASAR SDSS J010013.02+280225.8 at REDSHIFT 6.30

We report exploratory Chandra observations of the ultraluminous quasar SDSS J010013.02+280225.8 at redshift 6.30. The quasar is clearly detected by Chandra with a possible component of extended emission. The rest-frame 2-10 keV luminosity is 10⁴⁵ erg s^-1 with an inferred photon index of Γ = . This quasar is X-ray bright, with an inferred X-ray-to-optical flux ratio , higher than the values found in other quasars of comparable ultraviolet luminosity. The properties inferred from this exploratory observation indicate that this ultraluminous quasar might be growing with super-Eddington accretion and probably viewed with a small inclination angle. Deep X-ray observations will help to probe the plausible extended emission and better constrain the spectral features for this ultraluminous quasar.