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We present new Chandra X-ray Observatory and Hubble Space Telescopeobservations of eight optically selected broad-line AGN candidates in nearbydwarf galaxies ($z<0.055$). Including archival Chandra observations of threeadditional sources, our sample contains all ten galaxies from Reines et al.(2013) with both broad H$\alpha$ emission and narrow-line AGN ratios (6 AGNs, 4Composites), as well as one low-metallicity dwarf galaxy with broad H$\alpha$and narrow-line ratios characteristic of star formation. All eleven galaxiesare detected in X-rays. Nuclear X-ray luminosities range from $L_{0.5-7\rm{keV}}\approx5\times10^{39}$ to $1\times10^{42}$ $\rm{erg}\rm{s^{-1}}$. Inall cases except for the star forming galaxy, the nuclear X-ray luminositiesare significantly higher than would be expected from X-ray binaries, providingstrong confirmation that AGN and composite dwarf galaxies do indeed hostactively accreting BHs. Using our estimated BH masses (which range from$\sim7\times10^{4}-1\times10^{6}~M_{\odot}$), we find inferred Eddingtonfractions ranging from $\sim0.1-50\%$, i.e. comparable to massive broad-linequasars at higher redshift. We use the HST imaging to determine the ratio ofultraviolet to X-ray emission for these AGN, finding that they appear to beless X-ray luminous with respect to their UV emission than more massive quasars(i.e. $\alpha_{\rm OX}$ values an average of 0.36 lower than expected based onthe relation between $\alpha_{\rm OX}$ and $2500{\rm \AA}$ luminosity).Finally, we discuss our results in the context of different accretion modelsonto nuclear BHs.

X-ray and Ultraviolet Properties of AGN in Nearby Dwarf Galaxies