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Physics Letters B 774 (2017) 195–204
Contents lists available at ScienceDirect
Physics Letters B
www.elsevier.com/locate/physletb
Triple Higgs coupling effect on h
0
→b
¯
b and h
0
→τ
+
τ
−
in the 2HDM
A. Arhrib
a
, R. Benbrik
b,∗
, J. El Falaki
a
, W. Hollik
c
a
Abdelmalek Essaadi University, Faculty of Sciences and Techniques, Tanger, Morocco
b
MSISM Team, Faculté Polydisciplinaire de Safi, Sidi Bouzid, B.P. 4162, Safi, Morocco
c
Max Planck Institut für Physik, Föhringer Ring 6, 80805 München, Germany
a r t i c l e i n f o a b s t r a c t
Article history:
Received
15 August 2017
Received
in revised form 21 September
2017
Accepted
21 September 2017
Available
online 25 September 2017
Editor: J.
Hisano
We study the one-loop electroweak radiative corrections to h
0
→ b
¯
b and h
0
→ τ
+
τ
−
in the framework
of two Higgs doublet Model (2HDM). We evaluate the deviation of these couplings from their Standard
Model (SM) values. h
0
→b
¯
b and h
0
→τ
+
τ
−
may receives large contribution from triple Higgs couplings
h
0
H
0
H
0
, H
0
h
0
h
0
, h
0
A
0
A
0
and h
0
H
+
H
−
which are absent in the Standard Model. It is found that in
2HDM, these corrections could be significant and may reach more than 12% for not tow heavy H
0
or A
0
or H
±
. We also study the ratio of branching ratios R = BR(h
0
→ b
¯
b)/BR(h
0
→ τ
+
τ
−
) of Higgs boson
decays which could be used to disentangle SM from other models such as 2HDM.
© 2017 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license
(http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP
3
.
1. Introduction
A Higgs-like particle has been discovered in the first run of the
LHC with 7 and 8 TeV energy in 2012 [1,2]. The combined mea-
sured
Higgs boson mass obtained by the ATLAS and CMS collabo-
rations
based on the data from 7 and 8 TeV is m
h
=125.09 ±0.21
(stat.)
±0.11 (syst.) GeV [3]. ATLAS and CMS also performed sev-
eral
Higgs coupling measurements, such as Higgs couplings to
W
+
W
−
, ZZ, γγ, b
¯
b and τ
+
τ
−
with 20–30% uncertainty, while
the coupling to b
¯
b still suffers from a large uncertainty of 40–50%.
One of the tasks of the new LHC run at 13 TeV (and 14 TeV) would
be to improve all the aforementioned measurements and to per-
form
new ones such as accessing h
0
→ γ Z as well as the triple
self-coupling of the Higgs boson. It is expected that the new LHC
run will pin down the uncertainty in h
0
→b
¯
b and h
0
→ τ
+
τ
−
to
10–13% and 6–8% for bottom quarks and tau leptons, respectively.
These measurements will be further ameliorated by the High Lu-
minosity
option for the LHC (HL-LHC) down to uncertainties of
4–7% for b quarks and 2–5% for τ leptons [4]. Moreover, in the
clean environment of the e
+
e
−
Linear Collider (LC), which can act
as a Higgs factory, the uncertainties on h → b
¯
b and h
0
→ τ
+
τ
−
would be much smaller reaching 0.6% for the couplings in h
0
→b
¯
b
and
1.3% for those in h
0
→τ
+
τ
−
[5,6].
*
Corresponding author.
E-mail
addresses: aarhrib@gmail.com (A. Arhrib), r.benbrik@uca.ac.ma
(R. Benbrik),
jaouad.elfalaki@gmail.com (J. El Falaki), hollik@mpp.mpg.de
(W. Hollik).
The above accuracies on fermionic Higgs decay measurements,
if reached, are of the size comparable to the effects of radiative cor-
rections
to some Higgs decays. Therefore, one can use these radia-
tive
correction effects to distinguish between the Standard Model
(SM) and various beyond-standard models. In this respect, pre-
cise
calculations of Higgs-boson production and decay rates have
been performed already quite some time ago with great achieve-
ments
(see e.g. [7,8]). QCD corrections to Higgs decays into quarks
are very well known up to O(α
3
s
) as well as additional correc-
tions
at O(α
2
s
) that involve logarithms of the light-quark masses
and also heavy top contributions [7]. Electroweak radiative correc-
tions
to fermionic decays (b
¯
b and τ
+
τ
−
) of the Higgs boson in the
SM are also well established [9–11] in the on-shell scheme. In the
framework of the Two-Higgs-Doublet Model (2HDM), several stud-
ies
have been carried out to evaluate the electroweak corrections
to fermionic Higgs decays [12–14]. The calculation of Ref. [12] is
done in the on-shell scheme except for the Higgs field renormal-
ization
where the MS subtraction has been used, while the one of
Ref. [13] is performed using the on-shell renormalization scheme
of [15].
In this paper, we will study the effects of electroweak radia-
tive
corrections to h
0
→ b
¯
b and h
0
→ τ
+
τ
−
decays in the 2HDM
taking into account theoretical constraints as well as experimen-
tal
restrictions from recent LHC data and other experimental re-
sults.
For h
0
→ b
¯
b we will update our results from [12] while for
h
0
→τ
+
τ
−
we will compute these effects for the first time follow-
ing
the same renormalization procedure described in [12]. Similar
studies have been performed in [16,17] to which we will compare
https://doi.org/10.1016/j.physletb.2017.09.065
0370-2693/
© 2017 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by
SCOAP
3
.