SUSY after LHC 2011 Data: A Brief Look 重庆 杨 金 民 中国科学院 理论物理研究所

Outline Implication of sparticle search results 1 Introduction Implication of Higgs search results 2 Implication of LHC results on SUSY 3 Conclusion and outlook

1 Introduction What is SUSY Why believe SUSY Models of SUSY ---Warm up SUSY

What is SUSY ? Edward Witten

 cosmic dark matter (WIMP) Edward Witten Why believe SUSY ?

Edward Witten

Targets of LHC SUSY mSUGRA GMSB … NMSSM MSSM AMSB Models:

2 SUSY search results and implications Higgs search results and implications Sparticle search results and implications LHC (7TeV, 5/fb)

2.1 Sparticle search results at LHC null results First two generations of squarks > 1 TeV If only 3rd generation sfermions are light, then gluino > 600~800 GeV 3rd generation squarks > 200~300 GeV

Any implication from sparticle search results ? First two generations of squarks are heavy (> TeV) The 3rd generation squarks may still be light  Effective SUSY (Natural SUSY) Low energy SUSY (M SUSY < TeV) seems not true ~

LHC: 3-sigma at 125 GeV Tevatron: 2.2-sigma in GeV 2.2 Higgs boson search results and implication (di-photon signal rate is above SM prediction)

If a light fundamental Higgs boson exists, SUSY is a paradise for Higgs SM is not a natural, comfortable place for Higgs ---a peaceful, harmonious place for Higgs Then theoretically (naturalness, hierarchy problem): 125 GeV Higgs: support SUSY !

SUSY: M h < 90 GeV at tree-level M h < 130 GeV at loop-level

It needs loop effects (mainly from stops) However, 125 GeV Higgs is not so comfortable for SUSY  heavy stops little fine-tuning

Let’s check Higgs mass in some SUSY Models: MSSM, NMSSM, nMSSM, … CMSSM (mSUGRA, GMSB, AMSB, … )

Higgs mass in mSUGRA ( ≤ 125 GeV) Cao, Heng, Li, Yang, arXiv:

Higgs mass in AMSB (<125 GeV) Baer, Barger, Mustafayev, arXiv:

Higgs mass in GMSB (<125 GeV) Baer, Barger, Mustafayev, arXiv:

How to repair GMSB to give a 125 GeV Higgs ?

One way to repair GMSB: Kang, Li, Liu, Tong, Yang, arXiv:

Cao, Heng, Liu, Yang, arXiv: Higgs mass in MSSM, NMSSM, nMSSM (125 GeV OK !)

Higgs decay to dark matter in SUSY Cao, Heng, Yang, Zhu, arXiv:

Higgs decay to dark matter in SUSY: detectable at LHC ? Cao, Heng, Yang, Zhu, arXiv:

Take a careful look at MSSM and NMSSM: Cao, Heng, Yang, Zhang, Zhu, arXiv: MSSM: NMSSM:

How to enhance the di-photon rate at the LHC ? NMSSM: it is easy h-b-b coupling can be suppressed so B(h  ) can be enhanced MSSM: it is hard h-b-b coupling cannot be suppressed need a light stau to enhance h  coupling gg  h   hgg coupling not enhanced to enhance B(h  )

How about pp  h  ZZ * (WW* ) at the LHC ?

Implication for XENON100:

3 Conclusion and outlook From Higgs search (125 GeV Higgs):

From sparticle search: First two generations of squarks are heavy (> TeV) The 3rd generation squarks may still be light  Natural SUSY + NMSSM Higgs search: Sparticle search: = Natural NMSSM

Some guess (outlook): Discover stop, sbottom and gluino (but no other squarks)  Natural SUSY Discover gluino and/or chargino (but no any sfermions)  Split-SUSY Discover nothing (no sparticles)  High-scale SUSY

Thanks !