Enhancing $t\bar{t}hh$ production through CP-violating top-Higgs interaction at the LHC, ILC and a 100 TeV collider

Understand

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, $t \bar{t} hh$ 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 $t\bar t$ in the final states may efficiently suppress the backgrounds.
• However, such a kind of process is also controlled by the top-Higgs coupling.