Double Higgs boson production and Higgs self-coupling extraction at CLIC

Abstract

The Compact Linear Collider (CLIC) is a future electron-positron collider that will allow measurement of the trilinear Higgs self-coupling in double Higgs boson events produced at its high-energy stages with collision energies of $\sqrt{s}$ = 1.5 and 3 TeV. The sensitivity to the Higgs self-coupling is driven by the measurements of the cross section and the invariant mass distribution of the Higgs-boson pair in the W-boson fusion process, e${}^{+}$e${}^{-}\to$HH${\nu }_e{\bar{\nu }}_e$. It is enhanced by including the cross-section measurement of ZHH production at 1.5 TeV. The expected sensitivity of CLIC for Higgs pair production through W-boson fusion is studied for the decay channels bbbb and bbWW using full detector simulation including all relevant backgrounds. With an integrated luminosity of $\mathcal{L}$ = 5 ab${}^{-1}$ at $\sqrt{s}$ = 3 TeV, CLIC will be able to measure the trilinear Higgs self-coupling with a relative uncertainty of $-8\%$ and $+11\%$ at $68\%$ C.L., assuming the Standard Model.

Comments: 16 pages, 12 figures, v3 for submission to EPJC