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We apply the jet model developed in the preceding paper of Zdziarski et al.to the hard-state emission spectra of Cyg X-1. We augment the model for theanalytical treatment of the particle evolution beyond the energy dissipationregion, and allow for various forms of the acceleration rate. We calculate theresulting electron and emission spectra as functions of the jet height, alongwith the emission spectra integrated over the outflow. The model accounts wellfor the observed radio, infrared, and GeV fluxes of the source, although theavailable data do not provide unique constraints on the model free parameters.The contribution of the jet emission in the UV--to--X-ray range turns out to bein all the cases negligible compared to the radiative output of the accretioncomponent. Nevertheless, we find out that it is possible to account for theobserved flux of Cyg X-1 at MeV energies by synchrotron jet emission, in accordwith the recent claims of the detection of strong linear polarization of thesource in that range. However, this is possible only assuming a very efficientparticle acceleration leading to the formation of flat electron spectra, andjet magnetic fields much above the equipartition level.

Jet contributions to the broad-band spectrum of Cyg X-1 in the hard state