LHCb Accomplishments S. Stone 1 NSF, Nov. 5, 2013 & Future Physics

The LHCb Collaboration 667 Authors 62 Institutes 16 Countries  4 Groups from USA Basking in light of 2008 Nobel Prize to Kobayshi & Maskawa, “ for the discovery of the origin of the broken symmetry which predicts the existence of at least 3 families of quarks” NSF, Nov. 5,

The LHCb Detector Complementary to ATLAS & CMS Built to exploit correlated bb production NSF, Nov. 5,  B (rad) Production  Of B vs B

NSF, Nov. 5, Detector

 sensors R sensors B-Vertex Measurement Vertexing: trigger on impact parameter measurement of decay distance (time) DsDs BsBs KK KK KK  d~1cm 47  m 144  m 440  m Primary vertex Decay time resolution = 40 fs  ) ~40 fs Example: B s → D s K Vertex Locator (Velo) Silicon strip detector with ~ 5  m hit resolution  30  m IP resolution 5 NSF, Nov. 5, 2013

Momentum and Mass measurement Momentum meas. + direction (VELO): Mass resolution for background suppression 6 NSF, Nov. 5, 2013  b tag BsBs KK KK    K   DsDs Primary vertex B s → D s K Mass resolution  ~15 MeV BoBo m(D s K) o - +

1 TeV Scale New Particles Naturalness  Higgs is most sensitive to physics of order M=125 GeV, has been pushed to ~1 TeV due to absence of signals. Can be pushed higher. (Soni suggests 10 TeV for KK)  But corrections to Higgs mass go as M 2, so can’t push M too high without getting into fine tuning problem  Need New Physics to cut off quantum corrections Suggested NP mechanisms: SUSY, Higgs compositeness, and extra dimensions. Each predicts a rich spectrum of new states NSF, Nov. 5,

Seeking New Physics HFP as a tool for NP discovery  While measurements of fundamental constants are fun, the main purpose of HFP is to find and/or define the properties of physics beyond the SM  HFP probes large mass scales via virtual quantum loops. An example, of the importance of such loops is the Lamb shift in atomic hydrogen  A small difference in energy between 2S 1/2 & 2P 1 /2 that should be of equal energy at lowest order NSF, Nov. 5,

Flavor as a High Mass Probe Already excluded ranges if c i ~1 , take c i = 1 NSF, Nov. 5, i See: Isidori, Nir & Perez arXiv: ; Neubert EPS 2011 talk See: Isidori, Nir & Perez arXiv: ; Neubert EPS 2011 talk Ways out 1.New particles have large masses >>1 TeV 2.New particles have degenerate masses 3.Mixing angles in new sector are small, same as in SM (MFV) 4.The above already implies strong constrains on NP Ways out 1.New particles have large masses >>1 TeV 2.New particles have degenerate masses 3.Mixing angles in new sector are small, same as in SM (MFV) 4.The above already implies strong constrains on NP New physics ruled out from  i =0 to somewhere in the blue boxes New physics ruled out from  i =0 to somewhere in the blue boxes

Limits on NP Higgs Yukawa’s (Harnik, Kopp & Zupan arXiv: ) NSF, Nov. 5,

A few b decay results “The success of the LHCb experiment has so far been a nightmare for all flavour physicists…” Gauld, Goetz and Haisch arXiv:1310:1082 NSF, Nov. 5,

 m s from B s →D s +  - NSF, Nov. 5,

CPV in B s →J/  X CP violation means, for example, that a B will have a different decay rate than a B Can occur via interference between mixing & decay For f =J/   or J/  f 0 Small CPV expected, good place for NP to appear NSF, Nov. 5,

background f (980) peak, now use larger range 0  s from B s →J/     f 0 Mode predicted by Stone & Zhang, found by LHCb In region between arrows, measured to be >97.7% cl NSF, Nov. 5,

 s results NSF, Nov. 5, Combined LHCb values:  (ps -1 ).  (ps -1 )  s =  (rad) Indications of large  s from CDF/D0 not confirmed

Bs→Bs→ SM branching ratio is (3.2±0.2)x10 -9 [Buras arXiv: ], NP can make large contributions. Many NP models possible, not just Super-Sym 16 NSF, Nov. 5, 2013 Standard Model MSSM ~tan 6 

NSF, Nov. 5, 2013 Evidence for B s →     17 BDT BsBs BoBo B→h + h - B→  B→  3/fb CMS 25/fb

Fake D + D+D+ Dfb Prompt D + LHCb D + →K -  +  + Production fractions: B→DX  use equality of  sl & known  ’s 18 NSF, Nov. 5, 2013 D s →K - K+ -  + DsDs Also D o,  b Must know #B s to measure B Must know #B s to measure B

Also B→Dh - LHCb measures f s /f d =0.259±0.015 Used by CMS & ATLAS P t dependence now evident, CMS/ATLAS implications NSF, Nov. 5, D-+D-+ D-+D-+ D-K+D-K+ D-K+D-K+ Ds-+Ds-+ Ds-+Ds-+

Implications NSF, Nov. 5,

A sample of other results NSF, Nov. 5,

Electroweak Unique x-Q 2 regions for structure function studies NSF, Nov. 5,

Central exclusive production NSF, Nov. 5, J/ 

Publications NSF, Nov. 5, Syracuse authored ~20% of LHCb papers Syracuse authored ~20% of LHCb papers

LHCb Upgrade Can accumulate data ~x10 the rate in hadronic channels, ~x5 in dimuon channels Relies on triggering at ~40 MHz without hard wired cuts by using detached vertices Requires replacing all electronics except calorimeter & muon, including rebuilding VELO, UT, TT & replacing RICH HPD’s Allows us to extend range of mass probed for new physics by a significant factor NSF, Nov. 5,

Upgrade physics NSF, Nov. 5, ✓ ✓ ✓ = Syracuse analysis ✓ ✓ ✓ ✓ ✓ ✓ MIT

Importance of the UT Use VELO-UT in trigger to improve throughput (see M. Williams talk) Reduces ghosts in tracking Essential for K S reconstruction for decays after the VELO NSF, Nov. 5,

Conclusions LHCb is now sensitive to potential New Physics effects at high mass scales We are searching for and limiting New Physics, especially in rare and CP violating b & c decays In addition there are important research directions in other areas: light meson structure qq versus tetraquark, exotic mesons, central exclusive production, electroweak physics…. The upgrade will allow much more sensitive searches in a variety of areas 28 NSF, Nov. 5, 2013

The End 29 NSF, Nov. 5, 2013