An exploratory study of Higgs-boson pair production

• Published in: The journal of high energy physics Vol. 2015; no. 8; pp. 1 - 42
• Main Authors: Lu, Chih-Ting, Chang, Jung, Cheung, Kingman, Lee, Jae Sik
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-08-2015
• Subjects: Classical and Quantum Gravitation; Coupling; Cross sections; Decomposition; Elementary Particles; Higgs bosons; Mathematical analysis; Pair production; Photons; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Regular Article - Theoretical Physics; Relativity Theory; String Theory; Texts; Phenomenological Models; Hadronic Colliders
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP08(2015)133

A
bstract
Higgs-boson pair production is well known being capable to probe the trilinear self-coupling of the Higgs boson, which is one of the important ingredients of the Higgs sector itself. Pair production then depends on the top-quark Yukawa coupling
g
t
S
,
P
, Higgs trilinear coupling
λ
3
H
, and a possible dim-5 contact-type
ttHH
coupling
g
tt
S
,
P
, which may appear in some higher representations of the Higgs sector. We take into account the possibility that the top-Yukawa and the
ttHH
couplings involved can be CP violating. We calculate the cross sections and the interference terms as coefficients of the square or the 4th power of each coupling (
g
t
S
,
P
, λ
3
H
, g
tt
S
,
P
) at various stages of cuts, such that the desired cross section under various cuts can be obtained by simply inputing the couplings. We employ the
H
H
→
γ
γ
b
b
¯
decay mode of the Higgs-boson pair to investigate the possibility of disentangle the triangle diagram from the box digram so as to have a clean probe of the trilinear coupling at the LHC. We found that the angular separation between the
b
and
b
¯
and that between the two photons is useful. We obtain the sensitivity reach of each pair of couplings at the 14 TeV LHC and the future 100 TeV
pp
machine. Finally, we also comment on using the
b
b
¯
τ
+
τ
−
decay mode in appendix.