Enhancing tthh production through CP-violating top-Higgs interaction at the LHC, ILC and a 100 TeV collider
Abstract
The measurement of Higgs self-coupling is one of the most crucial physics goals at the future colliders. At the LHC, the di-Higgs production is a main way to measure the Higgs trilinear coupling. As a complementary to the di-Higgs production, t t hh process may open a new avenue to measure di-Higgs physics at the LHC and a future 100 TeV pp collider or a high energy e+e- collider since the extra t t in the final states may efficiently suppress the backgrounds. However, such a kind of process is also controlled by the top-Higgs coupling. In this work, we investigate the impact of CP-violating top-Higgs coupling on tthh production at the LHC, ILC and a 100 TeV hadron collider under the current Higgs data. Within 2σ Higgs data allowed parameter region, we find that the cross section of tthh at the LHC-14 TeV, ILC-1 TeV and VHE-LHC/SPPC-100 TeV can be enhanced up to 2.1 times the SM predictions. The future precise measurement of Higgs coupling will reveal the nature of top-Higgs interaction and improve the sensitivity of the determination of Higgs self-coupling through tthh production.