String balls at the LHC and beyond

In string theory, black holes have a minimum mass below which they transition into highly excited long and jagged strings—“string balls”. These are the stringy progenitors of black holes; because they are lighter, in theories of TeV-gravity, they may be more accessible to the LHC or the VLHC. They share some of the characteristics of black holes, such as large production cross sections. Furthermore, they evaporate thermally at the Hagedorn temperature and give rise to high-multiplicity events containing hard primary photons and charged leptons, which have negligible standard model background. Finally, as expected from the correspondence principle, the string ball cross section at the correspondence point matches the enormous black hole production cross section. This may help dispel concerns that the black hole production rate is suppressed.