Post on 20-Dec-2015
Doubly charged Higgs bosons at Hadron Colliders and neutrino mass hierarchy
Mayumi Aoki (KEK)
A.G.Akeroyd and M.A. PRD72,035011 (2005) (hep-ph/0506176)
Motivation
( Q=I3+Y/
2 ) 0
2
( ). . . .
2i j i jT
ij iL jL ij i j i j
l lL h Ci h c h l l h c
2/
2/0
The observed neutrino oscillation data predict nonzero neutrino masses and mixings.
• Higgs Triplet Model : SM + Δ SU(2)L Higgs triplet boson (Y=2)
GeVmH
001•LEP
The most striking signature of Δ would be the observation of H±±.
H±± →ℓi±ℓj
± strong search potential
• Hadron colliders
scatteringBhabha
eeHee
HHZee
** , jiH decay with
Motivation
CDF Collab. PRL93(2004)
GeV
GeVe
GeVmeeHH
136
115
133
HHZpp **,
Assuming B(H±±→li±lj±)=100%
240pb-1 of data collected at √s=1.96TeV
CDFIITevatron
)( WHH
•Single production of H±± HHWpp *
•Nonleptonic decay (for m H±±> m H± )
•H±±→li±lj± in light of neutrino data
We study the search potential for H±± at Tevatron in HTM.
only
1
B.Dion et al, PRD59 (1999)
E.J.Chun et al, PLB566(2003)S.Chakrabarti et al, PLB434 (1998)
J.F.Gunion et al, hep-ph/9610237
Higgs Triplet Model
Δ 0 develops a
VEV :
)eV 75.0 WMAP( , 2 iijij mhm
•Neutrino mass matrix
eV 10 10 roughly very : LFV 3 ijh
We are interested in
.~ M
03.0 10|1| 3
20
2
2
M
(*),5
,5
,00
00
WHHmmmHmmm
AHHH
HHAH
0 0
000 ,,,),( hAHHH Physical Higgs bosons
2 † † 2 2 † † 2 †1 2 3
† † † †4 5 2
( ) ( ) Tr( ) [Tr( )] + Det( )
( )Tr( ) ( ) ( . .)Ti
V m M
i h c
doublet SM Higgs :
HHWppHHZpp *** ,,Production of H±± at Tevatron
)(2)( HHppHHppH Total H±±cross section
Single H±± production can be as large as the pair production.Mass limit on mH±± increases significantly.
Decay of H±±
)8/(||)( 2 ijHji hSmH )()2(1 jijiforS
i
iji
ij mh 2
,
2 The total leptonic decay width depends on which solution to the neutrino mass hierarchy is realized.
Leptonic decay
real :)(2
13,2,1 i
Tij mVmmmdiagVh MNSMNS
3 2 1
2 1 3
21 2 3
~ ~ ATM
m m m
m m m
m m m m
Normal hierarchy (NH)Inverted hierarchy (IH)Degenerate (DG)
2/2
2/1
13
00
00
001
2/13/16/1
2/13/16/1
sin3/13/2
i
i
i
MNS
e
e
e
V
phases Majorana :phase Dirac
21
132
,:
16.02sin
GeV 20 HH mm eV2.0 im
Decay of H±±
)16/(36)( 342* GmMGWHH HWF G: phase space
factor
Nonleptonic decay H±± → H±W(* )
Current search strategy is
ineffective.
Current search strategy is effective. If H±± → ℓ± ℓ± are measured then the ratios of hij can be evaluated.
An order of magnitudeestimate of hij could be obtaiened.
HHmm
123 mmm : NH
Limit on mH±±
'''' )(2)2()( llllllll BHHppBBHHpp Bilepton cross section
case. violatingCP no and assume We 013
)(' jill llHBB
2009)(~GeV fb 1905 Hm
mH±± > 130 GeV (μμ)
: IH1 321 mmm
Majorana phase dependenceAssuming CP conservation, the following different patterns can be allowed.
or 0, 21
: IH2 321 mmm
mH±± > 138 GeV (ee) mH±± > 120 GeV (eμ)
: DG1 321 mmm
mH±± > 132 GeV (μμ)
: DG2 321 mmm
mH±± > 122 GeV (ee)
: DG3 321 mmm
mH±± > 105 GeV (eμ)
: DG4 321 mmm
mH±± > 115 GeV (μμ)
Summary
We have studied the search potential for H±± at Tevatron.
• Higgs Triplet Model : SM + Δ SU(2)L Higgs triplet boson (Y=2)
HHppHHpp ,
(*), WHllH ji
production
decay
We encourage a detailed experimental simulation of this decay mode at Tevatron.
significantly improves the search
potential for H±±
might be helpful to determine the absolute value of hij .
Neutrino mass spectrum might be distinguished by the leptonic decay mode.
LHC)()()( HHppHHppHHpp
H
Total H±±cross section
sensitivity up to 1 TeV