Unveiling the hosts of parsec-scale massive black hole binaries: morphology and electromagnetic signatures

Parsec-scale massive black hole binaries (MBHBs) are expected to form in hierarchical models of structure formation. Even though different observational strategies have been designed detect these systems, a theoretical study is further guide for their search and identification. In this work, we investigate the hosts properties electromagnetic signatures holes gravitationally bound on parsec-scales with primary mass $\rm {>}\,10^7\,M_{\odot}$. For that, construct full-sky lightcone by use semi-analytical model L-Galaxies which physically motivated prescriptions formation evolution MBHBs included. Our predictions show that large majority placed either spiral galaxies classical bulge or elliptical galaxies. Besides, scaling relations followed indistinguishable from ones single holes. We find occupation fraction parsec-scale reaches up ${\sim}\,50\%$ M_{stellar}\,{>}\,10^{11}\, M_{\odot}$ drops below 10\% M_{stellar}\,{<}\,10^{11}\, M_{\odot}$. anticipates unequal systems lie at $z\,{\sim}\,0.5$, ${\sim}\,20$ objects per deg^2$ sky. However, most inactive, only $1\,{-}\,0.1$ an counterpart bolometric luminosity excess $10^{43}$ erg/s. Very luminous phases more common $z\,{>}\,1$ but number ${\lesssim}\,0.01$ L_{\rm bol}\,{>}\,10^{45} \rm erg/s$.