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We present the results of a 100 ks {\it Chandra} observation of the NGC 404nuclear region. The long exposure and excellent spatial resolution of {\itChandra} has enabled us to critically examine the nuclear environment of NGC404, which is known to host a nuclear star cluster and potentially anintermediate-mass black hole (on the order of a few times $10^5$ \Msun). Wefind two distinct X-ray sources: a hard, central point source coincident withthe optical and radio centers of the galaxy, and a soft extended region that iscoincident with areas of high H$\alpha$ emission and likely recent starformation. When we fit the 0.3-8 keV spectra of each region separately, we findthe hard nuclear point source to be dominated by a power law (\PL = 1.88),while the soft off-nuclear region is best fit by a thermal plasma model ($kT$ =0.67 keV). We therefore find evidence for both a power law component and hotgas in the nuclear region of NGC 404. We estimate the 2-10 keV luminosity to be1.3$^{+0.8}_{-0.5}\times10^{37}$ erg s$^{-1}$. A low-level of diffuse X-rayemission is detected out to $\sim$15\as ($\sim$0.2 kpc) from the nucleus. Wecompare our results to the observed relationships between power law photonindex and Eddington ratio for both X-ray binaries and low luminosity activegalaxies and find NGC 404 to be consistent with other low luminosity activegalaxies. We therefore favor the conclusion that NGC 404 harbors anintermediate-mass black hole accreting at a very low level.

A Deep Chandra View of the NGC 404 Central Engine