  Heating signatures from small-scale magnetic reconnection events in the solar
atmosphere have proven to be difficult to detect through observations.
Numerical models that reproduce flaring conditions are essential in the
understanding of how nanoflares may act as a heating mechanism of the corona.
We study the effects of non-thermal electrons in synthetic spectra from 1D
hydrodynamic RADYN simulations of nanoflare heated loops to investigate the
diagnostic potential of chromospheric emission from small-scale events. The Mg
II h and k, Ca II H and K, Ca II 854.2 nm, H-alpha and H-beta chromospheric
lines were synthesised from various RADYN models of coronal loops subject to
electron beams of nanoflare energies. The contribution function to the line
intensity was computed to better understand how the atmospheric response to the
non-thermal electrons affects the formation of spectral lines and the detailed
shape of their spectral profiles. The spectral line signatures arising from the
electron beams highly depend on the density of the loop and the lower cutoff
energy of the electrons. Low-energy (5 keV) electrons deposit their energy in
the corona and transition region, producing strong plasma flows that cause both
redshifts and blueshifts of the chromospheric spectra. Higher-energy (10 and 15
keV) electrons deposit their energy in the lower transition region and
chromosphere, resulting in increased emission from local heating. Our results
indicate that effects from small-scale events can be observed with ground-based
telescopes, expanding the list of possible diagnostics for the presence and
properties of nanoflares.
