Speaker
Description
"A search for nonresonant triple Higgs boson (HHH) production in the final state
with six bottom quarks is performed using proton-proton collisions at √s = 13 TeV
corresponding to an integrated luminosity of 138 fb−1 recorded by the CMS experi-
ment. No significant excess of events over the background prediction is seen. Ob-
served (expected) 95% confidence level upper limits on the signal cross section are
set at 44 (43) fb, corresponding to 588 (572) times the standard model expectation.
The HHH process is directly sensitive to both the trilinear and quartic Higgs self-
couplings. The observed (expected) constraint on the quartic coupling modifier κ4 is
−177 < κ4 < 185 (−180 < κ4 < 190), assuming κ3 = 1. The corresponding con-
straint on the trilinear coupling modifier κ3 is−7.4 < κ3 < 12.4 (−6.4 < κ3 < 11.2),
assuming κ4 = 1. This analysis provides the most stringent constraint to date on non-
resonant HHH production and excludes, for the first time, part of the (κ3, κ4) space
allowed by the perturbative unitarity bound."
