Physics Letters B 756 (2016) 109–112
Contents lists available at ScienceDirect
Physics Letters B
www.elsevier.com/locate/physletb
Collider signatures of Higgs-portal scalar dark matter
Huayong Han
a
, Jin Min Yang
b,c
, Yang Zhang
b
, Sibo Zheng
a,∗
a
Department of Physics, Chongqing University, Chongqing 401331, PR China
b
Institute of Theoretical Physics, Academia Sinica, Beijing 100190, PR China
c
Department of Physics, Tohoku University, Sendai 980-8578, Japan
a r t i c l e i n f o a b s t r a c t
Article history:
Received
30 January 2016
Received
in revised form 2 March 2016
Accepted
2 March 2016
Available
online 7 March 2016
Editor:
J. Hisano
In the simplest Higgs-portal scalar dark matter model, the dark matter mass has been restricted to be
either near the resonant mass (m
h
/2) or in a large-mass region by the direct detection at LHC Run 1 and
LUX. While the large-mass region below roughly 3TeV can be probed by the future Xenon1T experiment,
most of the resonant mass region is beyond the scope of Xenon1T. In this paper, we study the direct
detection of such scalar dark matter in the narrow resonant mass region at the 14 TeV LHC and the future
100 TeV hadron collider. We show the luminosities required for the 2σ ex clusion and 5σ discovery.
© 2016 The Authors. Publishe d 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
New physics beyond the Standard Model (SM) has drawn ex-
tensive
attention since the discovery of the SM Higgs boson [1,2].
While a few problems such as how to stabilize the Higgs mass
against ultraviolet radiative corrections are tied to new physics of
high mass scale, in this paper we instead focus on dark matter
with a mass near the weak scale. In contrast to new physics which
appears at a rather high mass scale, such a dark matter model has
promising prospect for discovery at both astrophysical and particle
collider experiments.
In
particular, we are interested in the simplest Higgs-portal
dark matter model, in which the dark matter communicates with
SM particles via the Higgs scalar. Unlike the fermion dark matter
setting, a scalar dark matter in the so-called Higgs-portal scalar
dark matter model (HSDM) [3–7] still survives the latest data of
direct detections at Xenon100 [8] and LUX [9], indirect detections
at Fermi-LAT [10,11], and Higgs invisible decay at the LHC Run 1
[12]. Detailed discussions about this model have been given in the
literature [13–42]. Fitting the experimental data indicates that the
dark matter mass is either near the resonant mass region between
53 GeV and 62.5GeVor in a large-mass region above 185 GeV.
While
the large-mass region between 185 GeV and 3TeV can
be probed by the future Xenon1T [43], most of the resonant mass
region is beyond the reach of this facility. In this paper, we dis-
cuss
the collider signatures of the scalar dark matter in the HSDM
*
Corresponding author.
E-mail
address: sibozheng.zju@gmail.com (S. Zheng).
model with a mass between 53 GeV and 62.5GeVat the 14 TeV
LHC and the future 100 TeV proton collider (FCC). We will show
that similar to Circular Electron Positron Collider (CEPC) [44,45],
FCC will be a useful machine for searching dark matter in this nar-
row
mass region. We will show that for FCC with a luminosity of
10 ab
−1
the exclusion and discovery sensitivities reach to 57 GeV
and 56 GeV respectively through the Vector Boson Fusion (VBF)
channel, and 54.8 GeV and 53.9 GeV respectively via the mono-Z
channel.
It indicates that FCC with 10 ab
−1
is a competitive facility
in comparison with CEPC or Xenon1T.
The
remaining parts of the paper are organized as follows. In
Sec. 2, we briefly discuss the direct and indirect detection con-
straints
on the HSDM. In Sec. 3 we address the collider phe-
nomenologies
for the HSDM with dark matter mass in the narrow
resonant mass region at the 14 TeV LHC and the 100 TeV FCC,
where we focus on both the VBF channel and mono- Z channel.
Our main results are presented in Sec. 4, where we show the lu-
minosities
required for the 2σ exclusion and 5σ discovery. Finally
we conclude in Sec. 5.
2. Model and constraints
2.1. Model
In the simplest HSDM model, the dark matter s communicates
with the SM particles through the SM Higgs scalar. The Lagrangian
for this mode reads as
L =L
SM
+
1
2
(
∂
s
)
2
−
μ
2
s
2
s
2
−
κ
s
2
s
2
|H|
2
−
λ
s
2
s
4
, (1)
http://dx.doi.org/10.1016/j.physletb.2016.03.010
0370-2693/
© 2016 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
.