1. The Lightest Higgs Boson of mSUGRA, mGMSB and mAMSB:
Observability and Precision Analyses
at Present and Future Colliders
Shufang Su • U. of Arizona
A. Dedes, S. Heinemeyer, SS
G. Weiglein, hep-ph/

2. Motivation LEP results on Higgs searches-
LEP results on Higgs searches
95% CL mHSM  GeV , 1.7  mHSM  116 GeV
MSSM light Higgs boson h0 mh  135 GeV
Higgs searches soft SUSY-breaking parameters
MSSM: 105 new SUSY breaking parameters out of control
mechanism for SUSY breaking: (flavor blind)
predictive, relate Higgs sector to other SUSY particles
low energy MSSM
(visible sector)
105 parameters
SUSY-breaking
(hidden sector)
a few parameters
gauge-mediated SUSY breaking (GMSB)
gauge interaction
gravity
gravity-mediated SUSY breaking (SUGRA)
anomaly-mediated SUSY breaking (AMSB)
anomaly
something
S. Su ASBSII

3. Goal Individual analysis for each scenario and MSSM exists-
Individual analysis for each scenario and MSSM exists
(lots of references … )
We treat three soft SUSY-breaking scenarios equal
allow a direct comparison of results/phenomenology
Previous analyses
All parameters except one (e.g. mA) kept fixed
complete knowledge of SUSY parameters
unrealistic enhancement of sensitivity
Our analyses: mSUGRA, mGMSB, mAMSB
Vary all high-energy input parameters
Combine with mA/other SUSY particle mass from LHC
J.A. Bagger, K. Matchev, D.M. Pierce, R. zhang,
phys. Rev. D 55 (1997) 3188
K.T. Matchev, D.M. Pierce, phys. Lett. B 445 (1999) 331
W. de Boer, hep-ph/
T.A. Kaeding, S. Nandi, hep-ph/
S. Su, Nucl. Phys. B 573 (2000) 87
A. Dedes, S. Heinemeyer, P. Teixeira-Dias, G. Weiglein,
Jour. Phys. G 26 (2000) 582
B. Allanach, A. Dedes, JHEP 0006 (2000) 017
S. Ambrosanio, S. Heinemeyer, G. Weiglein,
hep-ph/ , hep-ph/
J. Ellis, G. Ganis, D.V. Nanopoulos, K.A. Olive,
Phys. Lett B 502 (2001) 171
A. Djouadi, M. Drees, J. Kneur, JHEP 0108 (2001) 055
J. Ellis, S. Heinemeyer, K. Olive, G. Weiglein,
Phys. Lett. B 515 (2001) 348, JHEP 0301 (2003) 006
J. Guasch, W. Hollik, S. Penaranda,
Phys. Lett. B 515 (2001) 367
M. Carena, H. Haber, H. Logan, S. Mrenna,
Phys. Rev. D 65 (2002)
S. Dawson, S. Heinemeyer, Phys. Rev. D 66 (2002)
S. Su ASBSII

4. Outline Introduction Procedure and additional constrains-
Introduction
MSSM Higgs sector
soft SUSY-breaking scenario: mSUGRA, mGMSB, mAMSB
Procedure and additional constrains
Observability of h0 at current and future colliders
Precision analyses of h0 decay branching ratio
Deviations in mSUGRA, mGMSB, mAMSB
Bounds on mA and high-energy input parameters
Distinguish three SUSY-breaking scenarios
Conclusions
S. Su ASBSII

5. MSSM Higgs sector Two Higgs doublet Higgs potential-
Two Higgs doublet
Higgs potential
Electroweak symmetry breaking
||, b are replaced by mZ, tan= v2/v1
Physical states: h0,H0,A0,H, Goldstone bosons: G0,G
S. Su ASBSII

6. Measurement of Higgs masses and couplings
CP-even Higgs h0,H0 -
In the 10-20 basis
Mass matrix
mA2=2b/sin 2
Tree level
mh < |cos 2|mZ < mZ
loop contribution to mh from t-t sector (dominant) 
(G.Degrassi, S.Heinemeyer, W.Hollik,
P.Slavich and G.Weiglein ’02)
Two loop calculation: mh  135 GeV
Measurement of Higgs masses and couplings
information about soft SUSY-breaking parameters
S. Su ASBSII

7. Present status of mh prediction in MSSM-
 Used for LEP analysis until 1999
RG improved one-loop effective potential results
Leading logs at two-loop level
program: subhole (M. Carena, M. Quiros, C. Wagner ’95)
 Used since end of 1999
Feynman-diagrammatic two-loop results
Complete one-loop + dominant two-loop corrections
program: FeynHiggs (S. Heinemeyer, W. Hollik, G. Weiglein ’98,’00,’01)
Remaining theoretical uncertainties in mh prediction
Unknown higher-order corrections  mh  3 GeV
- Uncertainties in input parameters mt,…,mA,tan,mt1,mt2,t,mg
mt  5 GeV  mh  5 GeV 
(G.Degrassi, S.Heinemeyer, W.Hollik, P.Slavich and G.Weiglein ’02)
Precise knowledge of mt is important
S. Su ASBSII

8. FD approach of MSSM Higgs sector-
Most relevant parameters for MSSM Higgs sector:
mA, tan, mt1, mt2, t, mb1, mb2, b, , mg, M1, M2. 
Use FD approach within on-shell renormalization scheme
mh, mH given by poles of the h0-H0 propagator matrix
Effective mixing angle eff
Fortran code: FeynHiggs
S. Su ASBSII

9. Minimal Super Gravity mediated SUSY-breaking (mSUGRA)
{ m0, m1/2, A0, tan, sign  }
m0 : common scalar mass at GUT scale
m1/2 : common gaugino mass at GUT scale
A0 : common trilinear scalar coupling at GUT scale
tan : low energy input
sign  : low energy input
S. Su ASBSII

10. Minimal Gauge mediated SUSY-breaking (mGMSB)
SUSY breaking is mediated by SM gauge interactions
through messenger sector
{ Mmess, Nmess, , tan, sign  }
Mmess : messenger mass scale
Nmess : messenger index
 : soft SUSY-breaking mass scale
S. Su ASBSII

11. Minimal Anomaly mediated SUSY-breaking (mAMSB)
SUSY breaking on a separate brane is communicated
to the visible sector via super-Weyl anomaly
{ maux, m0, tan, sign  }
maux : SUSY breaking scale (gravitino mass)
m0 : additional mass scale for scalar (to keep ml > 0 ) 
S. Su ASBSII

12. High-energy parameters in mSUGRA, mGMSB, mAMSB
Procedure -
High-energy parameters in mSUGRA, mGMSB, mAMSB
RG running
Further
constraints
EW precision data,
non-observation of
SUSY particles, etc.
Low-energy parameters
FeynHiggs (FD approach)
h0 production
and decay
Constraints on
mA,tan ...
Precision measurements
of h0 decay at LC and C
Distinguish
three scenarios
Observability at
Tevatron and LHC
S. Su ASBSII

13. High-energy input parameter
mSUGRA
mGMSB
mAMSB
50 GeV m0 1 TeV
10 TeV  200 TeV
20 TeV maux 100 TeV
50 GeV m1/21 TeV
1.01  Mmess105 
0 m0 2 TeV
-3 TeV A0 3 TeV
1 Nmess 8
1.5 tan 60
1.5 tan 55
sign = + 1
Positive : favored by g-2 and BR(b ! s )
S. Su ASBSII

14. Additional constraints-
LEP Higgs exclusion bounds
Precision observable:  SUSY  3  10-3
Experimental bounds on SUSY particle masses
mt=175 GeV (mh/ mt = 1 GeV/1 GeV)
No SUSY CP-violating phases
R-parity conserved
Success REWSB
No color/charge breaking minima
LSP uncolored and uncharged (neutralino LSP in mSUGRA and mAMSB)
Restrict to positive : favored by g-2 and Br(b ! s )
S. Su ASBSII

15. Previous work LEP Higgs searches : exclusion region in mh0-tan
S. Ambrosanio, A. Dedes, S. Heinemeyer, SS, G. Weiglein NPB 624, 3 (2002)
LEP Higgs searches : exclusion region in mh0-tan
Slight excess of 116 GeV Higgs
interpreted as light CP-even Higgs with SM-like coupling
corresponding SUSY particle spectrum
Strong enhancement of b, Yukawa coupling » sineff / cos  small mA, large tan
Strong suppression of h ! bb,  possible in mSUGRA
MSSM
SUGRA
GMSB
AMSB
mh0max (GeV)
135
127
123
125
tanmin
0.5 or 2.4
2.9
3.1
3.8
S. Su ASBSII

16. Higgs production and decay-
Tevatron
qq!V!Vh (V=W,Z)
LHC
gg!h
qq,gg!tt!tth
VV!h LC
e+e-!Z!Zh C
!h
(h! bb,cc,+-,+-): higher-order correction included
(h ! ,gg,WW): Hdecay (A.Djouadi, J.Kalinowski, M.Spira, ’97-’03)
S. Su ASBSII

17. Channels for Higgs study-
Higgs boson decay
Higgs study channels
Tevatron
qq ! V ! Vh ! Vbb (V=W,Z)
LHC
gg ! h ! , VV ! h ! +-, WW*, 
qq,gg ! tt ! tth ! ttbb LC
e+e- ! Z ! Zh ! Zbb,Zcc,Z+-,ZWW*,Zgg
WW! h ! bb,cc,+-,WW*,gg C
 ! h ! bb, WW*, 
S. Su ASBSII

18. Observability of h0 Tevatron LHC V ! Vh ! Vbb suppressed mGMSB-
Tevatron
V ! Vh ! Vbb suppressed
not more than 10%
discovery potential as good
as SM Higgs
LHC
mGMSB 10 30 40 50 20
1000
1400
600
200
1800
mA (GeV)
tan
gg ! h !  suppression
of 50% or more 10 30 40 50 20
1000
1400
600
200
1800
mA (GeV)
tan
mAMSB
mSUGRA 10 30 40 60 50 20
1000
1400
600
200
1800
mA (GeV)
tan
< 10% (mSUGRA, mGMSB)
upto 20% (mAMSB)
10-20% (mSUGRA, mGMSB)
< 10% (mAMSB)
S. Su ASBSII

19. Observability of h0 (cont’)-
LHC
qq,gg ! tt ! tth ! ttbb suppressed no more than 10%
VV ! h (Plehn, Rainwater, Zeppenfeld ’99, ’00)
mSUGRA
mGMSB, mAMSB
WW ! h ! +-
differ < 10%
enhanced everywhere
small mA, large tan
suppression
no suppression
WW ! h ! WW*, 
suppression at small mA LC
easily observable even with strong suppression
S. Su ASBSII

20. Observability of h0 (cont’)- C
mSUGRA
mGMSB, mAMSB
 ! h ! bb, +-
small suppression/ enhancement
always enhanced
very large tan
suppression
no suppression
 ! h ! WW*, 
suppression > 20%
suppression > 50%
mGMSB
mAMSB 50 50 40 40
tan  30
tan  30 20 20 10 10
 ! h ! 
400
800
1200
1600
400
800
1200
1600
S. Su ASBSII
mA (GeV)
mA (GeV)

21. Precision analyses of Higgs coupling-
concentrate on LC and C
focus on Higgs sector
Anticipated precision
h ! bb
1.5%
h ! +-
4.5% LC
h ! cc 6%
h ! gg 4%
h ! WW* 3% 2% C 5%
h !  
11%
direct detection of A0 difficult
deviation from SM Higgs coupling
 indirect bound on mA
differ from previous analyses
- all but one parameter kept fixed
require knowledge of SUSY
parameters
- scan over parameter space
reduced sensitivity
“worst case” scenario
§ n: § n £ precision
S. Su ASBSII

22. Sensitivity in mA-tan plane
mSUGRA
LC: h! WW*
1 mA  500 GeV
3 mA  550 GeV
2 mA  700 GeV
1 mA  1000 GeV
suppression in h! bb, +-
enhancement in h! cc, WW*
 35  tan  55
sensitivity in C slightly worse
S. Su ASBSII

23. Sensitivity in mA-tan plane (cont’)
mAmax (GeV)
-1
-2
-3
mSUGRA
1000
700
550
mGMSB
1150
750
600
mAMSB
1300
850
LC: h ! WW* no enhancement
mGMSB 10 30 40 50 20
1000
1400
600
200
1800
mA (GeV)
tan 10 30 40 50 20
1000
1400
600
200
1800
mA (GeV)
tan
mAMSB
S. Su ASBSII

24. Sensitivity to high-energy parameters
mSUGRA
mild bound on m0
stronger bound on m1/2 3 7 9
10£ 104 5
1000
1400
600
200 1
1800
m0 (GeV)
maux
mAMSB VVh!cc
mSUGRA
-1 
-2 
-3 
m1/2max (GeV)
650
450
350
mGMSB
deviation from SM coupling
not sufficient to constrain Mmess and 
small deviation 
lower bound on Mmess and 
mAMSB
2 , 3  deviation
wide range of m0 and maux
mAMSB
2 
3 
m0max (GeV)
1400
1100
mauxmax (GeV)
7.5£104
6£104
S. Su ASBSII

25. Distinguish SUSY Breaking Scenario-
500 GeV  mA  600 GeV
tan  30
AMSB
GMSB
SUGRA
if we know ranges of mA, tan from LHC
if we see deviations of coupling at LC
Can we distinguish various SUSY breaking scenario?
800 GeV  mt1  900 GeV ~
900 GeV  mg  1000 GeV ~
Yhbb » sineff/cos
12 ! eff
mSUGRA
large and negative
mGMSB
small
mAMSB
large and positive
S. Su ASBSII

26. Conclusion Investigate relevant production and decay channels of h0-
Investigate relevant production and decay channels of h0
- Tevatron, LHC, LC and C -mSUGRA, mGMSB and mAMSB
Observability
- Tevatron: as good as SM Higgs; LC: ensured
- LHC: gg ! h ! , C: h ! WW*, , small mA, large tan
problematic (mGMSB, mAMSB)
Precision measurement of BR at LC and C
bound on mA and tan: mA<1 TeV for 2-3  deviation
- biggest sensitivity from LC: h ! WW*, cc
- suppression in h ! bb, +-, enhancement in h ! cc, WW*
 35  tan  55 (mSUGRA)
bound on high-energy input parameters
- m1/2 (mSUGRA), m0 (mAMSB)
Distinguish different SUSY breaking scenarios
S. Su ASBSII