1/17
Hiroaki SUGIYAMA
(Univ. of Toyama, Japan)
Contents  Introduction
Higgs Triplet Model
Motivations
 Our Model - extended HTM  LHC Phenomenology
 Summary
based on ‘S. Kanemura, HS, arXiv:1202.5231’
2/17
Introduction
Neutrino masses are very different from other fermion masses.
neutrino-specific mechanism to generate their masses ?
Neutrino-specific mass term
Majorana mass :
(possible only for
)
to be compensated
by scalar fields
Only the SM Higgs boson has vev.
Extra Higgs bosons have vev.
etc.
etc.
3/17
Higgs Triplet Model
the SM + a complex Higgs triplet of
W. Konetschny and W. Kumer, PLB70, 433 (1977)
M. Magg and C. Wetterich, PLB94, 61 (1980)
T.P. Cheng and L.F. Li, PRD22, 2860 (1980)
J. Schechter and J.W.F. Valle, PRD22, 2227 (1980)
Neutrino Mass
Majorana
mass matrix
Soft breaking of
Yukawa tem
4/17
Higgs potential
: spontaneous breaking of
no NG-boson for
(“Majoron”)
: explicit breaking of
Yukawa interaction with a complex Higgs triplet
Majorana
mass matrix
5/17
Motivations
Small
option seems charming
Light new particles (ex.
)
production at LHC
Sizable new coupling constants (ex.
)
sizable LFV
なるほど
We want to suppress
6/17
ほう
We want to supply the dark matter to the HTM
7/17
Suppression of
parameter
Our model
Surprising model
Resolve these issues at once
(some relation between them)
Supplying DM candidate
“Idea is what resolves multiple issues at once”
- Shigeru Miyamoto -
8/17
Hiroaki SUGIYAMA
(Univ. of Toyama, Japan)
Contents  Introduction
Higgs Triplet Model
Motivations
 Our Model - extended HTM  LHC Phenomenology
 Summary
based on ‘S. Kanemura, HS, arXiv:1202.5231’
Our Model
9/17
S. Kanemura, HS, arXiv:1202.5231
HTM
SM
Only scalar sector
is extended.
broken by
Suppression of
: allowed
parameter
by
conservation at the tree level
: forbidden
おっ
: at the loop level
10/17
Our Model
HTM
SM
Only scalar sector
is extended.
odd particles
ほほぅ
is DM candidate
11/17
1-loop generation of
parameter by utilizing DM candidate
-odd particles
(Dark matter candidates)
contribute to the loop
なかまだー
“オリゼー ダイアグラム”
Estimation of Suppression of
Case of
12/17
(inert doublet DM)
DM
Example:
satisfy LEP-II and WMAP
おっ
E. Lundstrom et al., PRD79, 035013 (2009)
Case of
(inert singlet DM)
いいじゃん
Example:
13/17
Hiroaki SUGIYAMA
(Univ. of Toyama, Japan)
Contents  Introduction
Higgs Triplet Model
Motivations
 Our Model - extended HTM  LHC Phenomenology
 Summary
based on ‘S. Kanemura, HS, arXiv:1202.5231’
Hopeful Probe of
at the LHC :
14/17
やるなー
わー
: The most interesting decay because of
Good for BG reduction by imposing
Negligible
No
No
(See also, S. Kanemura and K. Yagyu, PRD85, 115009 )
Hopeful Probe of
at the LHC :
わー
15/17
とりあえず
かもすか
with
Negligible contribution from
For example,
Negligible
Hopeful Probe of
16/17
at the LHC :
わー
c.f. usual HTM for the case of
Additional leptons likely to exist.
かもすぞー
まかせろ
17/17
Summary
The Higgs Triplet Model is extended.
Dark matter candidate
(composed of and
)
one-loop
“one-loop”
A strong suppression of
parameter is possible.
For example,
(not small) would be probed
at the LHC
with
suppressed
18/17
Backup
19/17
Higgs Triplet Model
Yukawa interaction with a complex Higgs triplet
Higgs potential
Scalar Potential
20/17
Masses of
-Odd Scalars
21/17
Masses of
-Even Scalars
22/17
Constraint on Inert Doublet Scalar DM
23/17
E. Lundstrom et al., PRD79, 035013 (2009)