Download presentation
Presentation is loading. Please wait.
Published byWidya Sanjaya Modified over 6 years ago
1
Phenomenology of SUSY Models with Non-universal Sfermions
Kazuki Sakurai (Nagoya U. KEK Cambridge U.) In collaboration with S.-G. Kim, N.Maekawa, K.I.Nagao, M.M.Nojiri, Y.Shimizu, M.Takeuchi 蒲郡
2
Introduction SUSY is one of the promising candidates of Physics beyond the SM However MSSM has many parameters ( > 100 !!) Gauginos : Scalar fermion: (Sfermion)
3
Introduction SUSY is one of the promising candidates of Physics beyond the SM However MSSM has many parameters ( > 100 !!) We can deduce parameters Gauginos : Scalar fermion: (Sfermion)
4
Introduction SUSY is one of the promising candidates of Physics beyond the SM However MSSM has many parameters ( > 100 !!) We can deduce parameters SU(5) GUT: Gauginos : Scalar fermion: (Sfermion)
5
Introduction SUSY is one of the promising candidates of Physics beyond the SM However MSSM has many parameters ( > 100 !!) We can deduce parameters SU(5) GUT: Gauginos : Scalar fermion: (Sfermion)
6
Introduction SUSY is one of the promising candidates of Physics beyond the SM However MSSM has many parameters ( > 100 !!) We can deduce parameters SU(5) GUT: Gauginos : Scalar fermion: (Sfermion)
7
Introduction SUSY is one of the promising candidates of Physics beyond the SM However MSSM has many parameters ( > 100 !!) We can deduce parameters SU(5) GUT: Gauginos : Scalar fermion: (Sfermion) (at GUT scale)
8
Non-Universal Sfermion Masses
Can we deduce more ? ? ? ?
9
Non-Universal Sfermion Masses
Can we deduce more ? ? from FCNCs and EDMs: Degenerate and heavy Sfermion K0-K0bar mixing neutron EDM
10
Non-Universal Sfermion Masses
Can we deduce more ? ? from FCNCs and EDMs: Degenerate and heavy Sfermion K0-K0bar mixing neutron EDM
11
Non-Universal Sfermion Masses
Can we deduce more ? ? from Naturalness:
12
Non-Universal Sfermion Masses
Can we deduce more ? ? from Naturalness: Light stops and gaugino R.Dermisek, H.D.Kim, I.W. Kim ‘00
13
Non-Universal Sfermion Masses
Can we deduce more ? from Naturalness: Light stops and gaugino R.Dermisek, H.D.Kim, I.W. Kim ‘00
14
Non-Universal Sfermion Masses
Theoretically motivated (E6 SUSY GUT with Horizontal symmetry) N.Maekawa ‘02, ‘04, N.Maekawa, T.Yamashita ‘04
15
Non-Universal Sfermion Masses non-universal scenario at the LHC ?
Theoretically motivated (E6 SUSY GUT with Horizontal symmetry) N.Maekawa ‘02, ‘04, N.Maekawa, T.Yamashita ‘04 How can we check this non-universal scenario at the LHC ? ISAJET: for particle spectrum HERWIG: for event generation AcerDET: for detector simulation
16
Model Point & Collider Signature
Point A: Dominant SUSY LSP
17
Model Point & Collider Signature
Point A: Dominant SUSY Very high momentum jet many b-jets LSP We will see “a very high pT jet” and “many b jets” at LHC !!
18
Number of b-jets “4” b-jets in an event LSP
19
Number of b-jets “4” b-jets in an event --- Cut --- LSP
Hinchliff, et al. ’97, ATLAS collaboration ‘99 “4” b-jets in an event --- Cut --- LSP SUSY cut: Events/1fb-1 b-tagging efficiency = 60% # of b-tagged jets # of b jets is smeared by ξ(b)=60% , but we can see many b jets in an event
20
Comparison with famous Univ. Points
“Non-universal” Point A Small number of “0” b-jet events is characteristic of this scenario!! Events/1fb-1 “Universal” Famous model points SPS1a SPS2 SPS3 SPS4 SPS5 SPS6 SPS8 SPS9
21
Comparison with famous Univ. Points
“Non-universal” Point A Small number of “0” b-jet events is characteristic of this scenario!! Events/1fb-1 “Universal” Famous model points SPS1a SPS2 SPS3 SPS4 SPS5 SPS6 SPS8 SPS9 We can find that the squarks that are lighter than gluino are only the 3rd generation squarks!
22
The highest pT in an event
The highest pT jet Very high pT LSP The highest pT in an event (The highest pT is not b) pT(max) Events/40GeV/1fb-1
23
The highest pT in an event
The highest pT jet Very high pT The highest pT in an event (The highest pT is not b) Events/40GeV/1fb-1 pT(max) LSP
24
The highest pT in an event
The highest pT jet Very high pT LSP The highest pT in an event (The highest pT is not b) Events/40GeV/1fb-1 pT(max)
25
The highest pT in an event (The highest pT is b-tagged)
The highest pT jet can “not” be b-tagged Very high pT LSP The highest pT in an event (The highest pT is not b) The highest pT in an event (The highest pT is b-tagged) Events/40GeV/1fb-1 pT(max) Events/40GeV/1fb-1 pT(max) We can eliminate the very high pT quark jet by using b-tagging Difference between two figures tells us the 1st and 2nd generation squarks are much heaver than gluino!! can be b-tagged
26
Really Non-universal ? From “The # of b-jets distribution” and “The highest pT distribution”, we could demonstrate to distinguish our Non-universal scenario from several Universal model points even in 1 fb-1 at the LHC !!
27
Really Non-universal ? From “The # of b-jets distribution” and “The highest pT distribution”, we could demonstrate to distinguish our Non-universal scenario from several Universal model points even in 1 fb-1 at the LHC !! But, were we really able to say “We confirmed our non-universal scenario in the LHC simulation”?
28
Really Non-universal ? From “The # of b-jets distribution” and “The highest pT distribution”, we could demonstrate to distinguish our Non-universal scenario from several Universal model points even in 1 fb-1 at the LHC !! But, were we really able to say “We confirmed our non-universal scenario in the LHC simulation”? --- In Universal scenario --- The highest pT The 1st and 2nd generation squarks are much heavier than gluino possible if we take
29
Really Non-universal ? From “The # of b-jets distribution” and “The highest pT distribution”, we could demonstrate to distinguish our Non-universal scenario from several Universal model points even in 1 fb-1 at the LHC !! But, were we really able to say “We confirmed our non-universal scenario in the LHC simulation”? --- In Universal scenario --- The highest pT The 1st and 2nd generation squarks are much heavier than gluino possible if we take The # of b-jets The squarks that are lighter than gluino are only the 3rd generation squarks possible in large A0 One of the stops can be very light
30
Large |A0|, m0 scenario Point U : Point U
(Universal in sfermion flavor)
31
Large |A0|, m0 scenario Point U : Point U
(Universal in sfermion flavor) Point U Point U Point U # of b-tagged jets pT(max) (not b) pT(max) (b-tagged) Similar distributions to those of our Non-universal scenario are obtained !
32
Difference What is a difference between Non-univ. and Large |A0|, m0 scenarios ? Non-universal scenario : Large |A0|, m0 scenario : or (~50-70%) (~30-50%) (100%) If gluinosbottom chains can be found in events, we can distinguish theses two scenarios !
33
Difference Final states are similar, b×2 + W×2 !!
What is a difference between Non-univ. and Large |A0|, m0 scenarios ? Non-universal scenario : Large |A0|, m0 scenario : or (~50-70%) (~30-50%) (100%) If gluinosbottom chains can be found in events, we can distinguish theses two scenarios ! What is a difference between sbottom and stop chain ? gluino sbottom chain: gluino stop chain: Final states are similar, b×2 + W×2 !! It is not easy to find a difference of these two chains
34
Difference Focusing on χ20Z mode Non-universal : Large |A0|, m0 :
cannot open due to small m30 Non-universal : Large |A0|, m0 : [0%] [50~70%] [~100%] [100%] [0~10%] [10~30%] [30~50%] [~100%] The number of associate jets is different in χ20Z events !! Non-universal Z with a small number of jets Large |A0|, m0 Z with a large number of jets
35
Difference Focusing on χ20Z mode Non-universal : Large |A0|, m0 :
cannot open due to small m30 Non-universal : Large |A0|, m0 : [0%] [50~70%] [~100%] [100%] [0~10%] [10~30%] [30~50%] [~100%] The number of associate jets is different in χ20Z events !! Non-universal Z with a small number of jets Large |A0|, m0 Z with a large number of jets
36
Z boson and # of jets Since these are the only processes to produce Z boson in gl-gl events, if we find a Z boson together with a small number of jets in gl-gl events, we can find that the gluinosbottom chain exists!! We reduce sq-gl events with cut: The highest jet is b-tagged, pT<300GeV In gl-gl events, if we find Z and a small number of jets Non-universal Z and a large number of jets Large |A0|, m0 Point A Z-peak 2 lepton inv. mass (GeV)
37
Z boson and # of jets Since these are the only processes to produce Z boson in gl-gl events, if we find a Z boson together with a small number of jets in gl-gl events, we can find that the gluinosbottom chain exists!! We reduce sq-gl events with cut: The highest jet is b-tagged, pT<300GeV In gl-gl events, if we find Z and a small number of jets Non-universal Z and a large number of jets Large |A0|, m0 Point A We select # of jets in the events (η<2.5, pT>50GeV) 12 # of jets = 4 Z-peak 2 lepton inv. mass (GeV)
38
Z boson and # of jets Since these are the only processes to produce Z boson in gl-gl events, if we find a Z boson together with a small number of jets in gl-gl events, we can find that the gluinosbottom chain exists!! We reduce sq-gl events with cut: The highest jet is b-tagged, pT<300GeV In gl-gl events, if we find Z and a small number of jets Non-universal Z and a large number of jets Large |A0|, m0 Point A 20 # of jets = 5 We select # of jets in the events (η<2.5, pT>50GeV) 12 # of jets = 4 Z-peak 2 lepton inv. mass (GeV)
39
Z boson and # of jets Since these are the only processes to produce Z boson in gl-gl events, if we find a Z boson together with a small number of jets in gl-gl events, we can find that the gluinosbottom chain exists!! We reduce sq-gl events with cut: The highest jet is b-tagged, pT<300GeV In gl-gl events, if we find Z and a small number of jets Non-universal Z and a large number of jets Large |A0|, m0 Point A 20 # of jets = 5 15 # of jets = 6 We select # of jets in the events (η<2.5, pT>50GeV) 12 # of jets = 4 Z-peak 2 lepton inv. mass (GeV)
40
Z boson and # of jets Preliminary Point U Point A Point A
20 # of jets = 5 15 # of jets = 6 We select # of jets in the events (η<2.5, pT>50GeV) 12 # of jets = 4 Z-peak 2 lepton inv. mass (GeV)
41
Z boson and # of jets Preliminary Point U Point A
20 # of jets = 5 15 # of jets = 6 We select # of jets in the events (η<2.5, pT>50GeV) 12 # of jets = 4 Z-peak By seeing Z-peak events on various jet number cuts, we can distinguish our non-universal scenario from a large |A0|, m0 scenario ! 2 lepton inv. mass (GeV)
42
Summary A non-universal scenario (m30,m1/2<<m0) can be distinguished from several universal model points in very early stage in the LHC (Lint ~1fb-1) !! The number of b-jets distribution The highest pT jet distributions A large |A0|, m0 scenario produces similar signature to the non-universal scenario, though it has the universal scalar mass. We can distinguish these two scenario by seeing the Z-peak in various jet number cuts.
50
Plan Introduction Non-universal Sfermions LHC signature Summary
51
Model Point & Collider Signature
Point A: Dominant SUSY LSP
52
Model Point & Collider Signature
Point A: Dominant SUSY LSP
53
Model Point & Collider Signature
Point A: Dominant SUSY LSP We will see “a very high pT jet” and “many b jets” at LHC !!
54
the theory does not require fine tuning !
Introduction SUSY is one of the leading candidates of the models beyond the SM Gauge coupling unification Providing Dark Matter Solution for Gauge Hierarchy Problem even if SUSY If and are weak scale, the theory does not require fine tuning !
55
SUSY Flavor Problem Origin of mass is different between fermion and Sfermion. Fermion: EWSB with Yukawa SFermion: SUSY breaking
56
SUSY Flavor Problem Origin of mass is different between fermion and Sfermion. Fermion: EWSB with Yukawa SFermion: SUSY breaking Induce too large FCNC
57
SUSY Flavor Problem suppressed
Origin of mass is different between fermion and Sfermion. Fermion: EWSB with Yukawa SFermion: SUSY breaking Induce too large FCNC suppressed But, if sfermion masses are degenerate… anything FCNC constraints suggest Universality of Sfermion masses
58
SUSY Flavor Problem
60
SUSY Flavor Problem suppressed
Origin of mass is different between fermion and Sfermion. Fermion: EWSB with Yukawa SFermion: SUSY breaking But, if sfermion masses are degenerate… anything Induce too large FCNC suppressed FCNC constraints suggest Universality of Sfermion masses
61
SUSY Flavor Problem Origin of mass is different between fermion and Sfermion. Fermion: EWSB with Yukawa SFermion: SUSY breaking FCNC constraints suggest Universality of Sfermion masses
62
SUSY Flavor Problem suppressed
Origin of mass is different between fermion and Sfermion. Fermion: EWSB with Yukawa SFermion: SUSY breaking But, if sfermion masses are degenerate… anything Induce too large FCNC suppressed FCNC constraints suggest Universality of Sfermion masses
63
SUSY Flavor Problem
64
SUSY Flavor Problem Origin of mass is different between fermion and Sfermion. Fermion: EWSB with Yukawa SFermion: SUSY breaking But, if sfermion masses are degenerate… anything Induce too large FCNC
65
SUSY Flavor Problem
66
SUSY Flavor Problem
67
SUSY Flavor Problem
68
SUSY Flavor Problem
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.