  Recently, the possibility was pointed out by one of the present authors and
his collaborators that an effective naked singularity referred to as "a visible
border of spacetime" is generated by high-energy particle collision in the
context of large extra dimensions or TeV-scale gravity. In this paper, we
investigate the particle creation by a naked singularity in general dimensions,
while adopting a model in which a marginally naked singularity forms in the
collapse of a homothetic lightlike pressureless fluid. We find that the
spectrum deviates from that of Hawking radiation due to scattering near the
singularity but can be recast in quasi-thermal form. The temperature is always
higher than that of Hawking radiation of a same-mass black hole, and can be
arbitrarily high depending on a parameter in the model. This implies that, in
principle, the naked singularity may be distinguished from a black hole in
collider experiments.
