The Nature of Soft Excess in ESO 362-G18 Revealed by XMM-Newton and NuSTAR Spectroscopy

We present a detailed spectral analysis of the joint XMM-Newton and NuSTAR observations active galactic nuclei (AGN) in Seyfert 1.5 Galaxy ESO 362-G18. The broadband ($0.3\mbox{--}79$ keV) spectrum shows presence power-law continuum with soft excess below $2$ keV, iron K$\alpha$ emission ($\sim 6.4$ keV), Compton hump (peaking at $\sim 20$ keV). find that can be modeled by two different possible scenarios: warm ($kT_\mathrm{e}\sim0.2$ optically thick ($\tau\sim34$) Comptonizing corona; or relativistically-blurred reflection off high-density ($\log{[n_\mathrm{e}/\mathrm{cm}^{-3}]}>18.3$) inner disk. These models cannot easily distinguished solely from their fit statistics. However, low temperature ($kT_\mathrm{e}\sim20$ optical depth ($\tau\sim5$) hot corona required scenario are uncommon for AGNs. also 'hybrid' model, which includes both disk corona. Unsurprisingly, as this is most complex considered, provides best fit, more reasonable coronal parameters. In case, majority flux arises component. based on recent simulations coronae, it not clear whether such structure really exist accretion rates relevant 362-G18 ($\dot{m}\sim0.015$). This may therefore argue favor instead dominated relativistic reflection. Based we data would require compact ($h\sim3\,R_\mathrm{Horizon}$) around highly spinning ($a_\star>0.927$) black hole.