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Two XMM Newton observations of Nova V4743 Sgr (Nova Sgr 2002) were performedshortly after it returned to quiescence, 2 and 3.5 years after the explosion.The X-ray light curves revealed a modulation with a frequency of ~0.75 mHz,indicating that V4743 Sgr is most probably an intermediate polar (IP). TheX-ray spectra have characteristics in common with known IPs, with a hardthermal plasma component that can be fitted only assuming a partially coveringabsorber. In 2004 the X-ray spectrum had also a supersoft blackbody-likecomponent, whose temperature was close to that of the white dwarf (WD) in thesupersoft X-ray phase following the outburst, but with flux by at least twoorders of magnitude lower. In quiescent IPs, a soft X-ray flux componentoriginates at times in the polar regions irradiated by an accretion column, butthe supersoft component of V4743 Sgr disappeared in 2006, indicating a possibleorigin different from accretion. We suggest that it may have been due to anatmospheric temperature gradient on the WD surface, or to continuing localizedthermonuclear burning at the bottom of the envelope, before complete turn-off.An optical spectrum obtained with SALT 11.5 years after the outburst showed aprominent He II 4686A line and the Bowen blend, which reveal a very hot region,but with peak temperature shifted to the ultraviolet (UV) range. V4743 Sgr isthe third post-outburst nova and IP candidate showing a low-luminositysupersoft component in the X-ray flux a few years after the outburst.

V4743 Sgr, a magnetic nova?