We study the properties of black holes of mass 10 ^ { 4 } – 10 ^ { 11 } GeV in models with the fundamental scale of gravity at the TeV .
These black holes could be produced in the collision of a ultrahigh energy cosmic ray with a dark matter particle in our galactic halo or with another cosmic ray .
We show that QCD bremsstrahlung and pair production processes are unable to thermalize the particles exiting the black hole , so a chromosphere is never formed during Hawking evaporation .
We evaluate with HERWIG the spectrum of stable 4-dim particles emitted during the Schwarzschild phase and find that in all cases it is peaked at energies around 0.2 GeV , with an approximate 43 % of neutrinos , 28 % of photons , 16 % of electrons and 13 % of protons .
Bulk gravitons are peaked at higher energies , they account for a 0.4 % of the particles ( 16 % of the total energy ) emitted by the most massive black holes in n = 6 extra dimensions or just the 0.02 % of the particles ( 1.4 % of the energy ) emitted by a 10 TeV black hole for n = 2 .