Collider Constraints on Massive Gravitons
摘要
We explore the potential for discovering massive graviton-like spin-2 particles, interacting with standard model fields. These particles are produced in collisions involving photons at the Large Hadron Collider (LHC) and electron-positron ( \(e^{+}\) \(e^{-}\) ) collisions. Our investigation utilizes an effective theory, both with and without universal couplings. Specifically, we focus on a massive graviton, denoted as G, that is coupled to the electromagnetic field. The decay of G leads to a resonant excess of diphotons over the light-by-light scattering continuum at the LHC, as well as triphoton final states in \(e^{+}e^{-}\) colliders. By analyzing existing data, we establish the exclusion limits on the graviton-photon coupling, reaching down to approximately \(g_{G\gamma } \approx 1\text{--}0.05 \, \text{TeV}^{-1}\) for graviton masses ranging from \(m_{G}\) \(\approx \) 100 MeV to 2 TeV. With their expected full integrated, in the low-mass range, significant enhancements are anticipated at Belle II, potentially improving these bounds by a factor of 100. Conversely, at higher masses, the High-Luminosity Large Hadron Collider (HL-LHC) is expected to enhance limits by a factor of 4.