  In this paper, we compare the chemistry and the emission spectra of
nitrogen-dominated cool, warm, and hot ultra-short-period (USP) super-Earth
atmospheres in and out of chemical equilibrium at various surface pressure
scenarios ranging from 0.1 to 10 bar. We link the one-dimensional VULCAN
chemical kinetic code, in which thermochemical kinetic and vertical transport
and photochemistry are taken into account, to the one-dimensional radiative
transfer model, PETITRADTRANS, to predict the emission spectra of these
planets. The radiative-convective temperature-pressure profiles were computed
with the HELIOS code. Then, using PANDEXO noise simulator, we explore the
observability of the differences produced by disequilibrium processes with the
JWST. Our grids show how different surface pressures can significantly affect
the temperature profiles, the atmospheric abundances, and consequently the
emission spectra of these planets. We find that the divergences due to
disequilibrium processes would be possible to observe in cooler planets by
targeting HCN, C2H4, and CO, and in warmer planets by targeting CH4 with HCN,
using the NIRSpec and MIRI LRS JWST instruments. These species are also found
to be sensitive indicators of the existence of surfaces on nitrogen-dominated
USP super-Earths, providing information regarding the thickness of these
atmospheres.
