Speaker
Description
The search for gravity arising from large extra dimensions at collider energies is explored in the transplanckian regime, where the center-of-mass energy, $\sqrt{s}$, is much greater than both exchanged momentum, $Q$, and the extra dimension Planck mass scale $M_D$. The primary signature of large extra dimension gravity in the transplanckian regime is the production of high-mass dijet events (with dijet mass $M_{jj}\sim \sqrt{s}\gg M_D$) featuring large rapidity separation. In this regime, the dominant Standard Model background arises from quantum chromodynamics (QCD) in the Gribov-Regge limit ($\sqrt{s}\gg Q \gg \Lambda_{QCD}$). Accurately computing this QCD background requires employing the next-to-leading logarithmic (NLL) approximation within the Lipatov-Fadin-Kuraev-Balitsky (BFKL) framework. In the present study, both the signal of large extra dimension gravity and the NLL BFKL QCD background are evaluated for the High Luminosity LHC (HL-LHC) as well as future colliders like FCC-hh and CEPC-hh.
