We investigate the contribution of the beamed jet component to the high energy emission in young and compact extragalactic radio sources , focusing for the first time on the \gamma -ray band .
We derive predictions on the \gamma -ray luminosities associated with the relativistic jet assuming a leptonic radiative model .
The high energy emission is produced via Compton scattering by the relativistic electrons in a spherical region at the considered scales ( \lesssim 10 kpc ) .
Simulations show a wide range of \gamma -ray luminosities , with intensities up to \sim 10 ^ { 46 } -10 ^ { 48 } erg s ^ { -1 } depending on the assumed jet parameters .
We find a highly linear relation between the simulated X-ray and \gamma -ray luminosities that can be used to select candidates for a \gamma -ray detection .
We compare the simulated luminosity distributions in the radio , X-ray and \gamma -ray regimes with observations for the largest sample of X-ray detected young radio quasars .
Our analysis of \sim 4-year Fermi Large Area Telescope ( LAT ) data does not give any statistically significant detection .
However , the majority of the model-predicted \gamma -ray fluxes for the sample are near or below the current Fermi -LAT flux threshold and compatible with the derived upper limits .
Our study gives constraints on the minimum jet power ( L _ { jet,kin } / L _ { disk } > 0.01 ) , on a potential jet contribution to the X-ray emission in the most compact sources ( \lesssim 1 kpc ) and on the particles to magnetic field energy density ratio in broad agreement with equipartition assumption .