LHCb RESULTS 1 2 3 4 5 Introduction

LHCb RESULTS 1. 2. 3. 4. 5. Introduction B hh CP violation asymmetries EW gauge boson production New b, c spectroscopy and exclusive dimuons Some B rare decays and Majorana neutrinos Main LHCb highlights by Guy Wilkinson BSM with LHCb tomorrow 54 institutions, 15 countries 3 Spanish universities among them : Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 1

The LHCb Apparatus Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 2

The LHCb Trigger + Data acquisition Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 3

LHCb integrated luminosity 2011 7. 0 Te. V (1 fb-1 recorded) High efficieny (<90%) & good performance 2010 (37 pb-1 recorded) Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 4

CP-VIOLATION IN B hh DECAYS Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 5

CP violation , the challenge Noninvariance of fundamental forces under the combined action of charge conjugation (C) and parity (P) transformations is well established in the K 0 and B 0 meson systems 1 Recent results from LHCb also provided evidence of CP violation in the decays of D 0 meson: R. Aaij et al. (LHCb Collaboration) Phys. Rev. Lett. 108, 111602 (2012) Yet LHCb has found CP violation in the only neutral heavy meson that remains, the Bs : R. Aaij et al. (LHCb Collaboration) Phys. Rev. Lett. 108, 201601 , published 16 May 2012 1 J. H. Christenson, J. W. Cronin, V. L. Fitch, and R. Turlay, Phys. Rev. Lett. 13, 138 (1964). B. Aubert et al. (BABAR Collaboration), Phys. Rev. Lett. 87, 091801 (2001). K. Abe et al. (Belle Collaboration), Phys. Rev. Lett. 87, 091802 (2001). Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 6

CP violation , the challenge All current experimental measurements of CP violation in the quark flavor sector are generally well described by the Kobayashi-Maskawa mechanism which is embedded in the framework of the Standard Model (SM) 1. However, it is believed that the size of CP violation in the SM is not sufficient to account for the asymmetry between matter and antimatter in the Universe 2. Hence, additional sources of CP violation are being searched for as manifestations of physics beyond the SM. 1 2 N. Cabibbo, Phys. Rev. Lett. 10, 531 (1963). M. Kobayashi and T. Maskawa, Prog. Theor. Phys. 49, 652 (1973). W. -S. Hou, Chin. J. Phys. (Taipei) 47, 134 (2009), http: //psroc. phys. ntu. edu. tw/cjp/download. php? type=full&vol=47#=2&page=134. Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 7

Charmless Two-Body Decays Bs, d →h+ h- Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 8

Bs, d →h+ h- direct CP violation Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 9

Direct CP-asymmetry in Bs → K+ π- Phys. Rev. Lett. 108, 201601 Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 10

Annihilation Diagrams Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 11

Effective Bs →K+ K- Lifetime Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 12

Time Dependent B 0 → K+ π- Fit Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 13

Time Dependent CP Violation in B 0 → π+π- Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 14

Time Dependent CP Violation in Bs →K+ K- t 0 = 0. 95 ps Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 15

Summary on CPV asymmetries in Bs, d →h+ h- (see Paula Alvarez’s talk tomorrow) Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 16

Measurement of the Ds+ Ds- production asymmetry in 7 Te. V pp collisions LHCb-PAPER-2012 -009 May 4, 2012 LHCb has determined the overall production asymmetry of Ds mesons produced directly in pp collisions in the rapidity region 2. 0 < < 4. 5 and p. T > 2 Ge. V : Which is consistent with theoretical expectations 1 and , provides significant constraints on models of Ds production, and it is a key input for CP violation measurements. M. Chaichian and A. Fridman Phys. Lett. B 298 (1993) 218. E. Norrbin and R. Vogt ar. Xiv: hep-ph/0003056 E. Norrbin and T. Sjostrand Eur. Phys. J. C 17 (2000) 137. Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 17

Ds+ Ds- production asymmetry results Subtle sources of production asymmetries : - only c can form a charmed baryon - non-independent fragmentation process - even interference with S-waves - are they reduced at central rapidities? LHCb has reconstructed 771. 031 Ds mesons with 1 fb-1 , using both magnet polarities, and determined the +/ - detection asymmetries in (p, p. T) to 1%. Key idea: use the ratio of partial/full reconstructed D* S D 0 decays. D* RS WS Bernardo Adeva, USC D 0 K- + +( -) 3 -momentum determined from slow pion S reconstruction Winter Meeting IMFP-2012 Benasque 30 May , 2012 18

Ds+ Ds- production asymmetry Then use reconstructed Ds K+ K- decays to measure the production asymmetry. Note no significant CP violation in decay is expected 1 being a Cabibbo favoured mode. Overall production asymmetry AP = (-0. 33 0. 22 (stat. ) 0. 10 (syst. )) % 1 Y. Grossman, A. L. Kagan, and Y. Nir, Phys. Rev. D 75 (2007) 036008 S. Bergmann and Y. Nir JHEP 09 (1999) 031. Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 19

W, Z BOSON PRODUCTION WITH LHCb Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 20

Electroweak boson production at LHCb Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 21

EW boson production and PDFs Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 22

EW boson production ratios Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 23

W l signal Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 24

Results Z production Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 25

W production and W/Z ratios Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 26

Results W+- asymmetry Differential W+- asymmetry consistent with NNLO predictions Lepton pseudorapidity Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 27

Combined Electroweak Physics Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 28

b AND c SPECTROSCOPY Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 29

B** spectroscopy Mesons consisting of LIGHT / HEAVY quarks are an interesting laboratory to study QCD, just as the hydrogen atom was to understand QED. The states with L=0 and spin-parity 0 - (B) and 1 - (B*) are well established. But precision spectroscopy of orbitally excited B states is still undone. Properties predicted by HQET (Heavy Quark Effective Field Theory). , , 100 -200 Me. V/c 2 expected widths Subject of LHCb study Key idea : the spin of the heavy quark and the total spin Jl of the light degrees of freedom are separately conserved. Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 30

B** spectroscopy First precision measurement by CDF II CDF 2009 Phys. Rev. Lett. 102 (2009) 102003. Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 31

B** spectroscopy How LHCb reconstructs B** states Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 32

B** spectroscopy LHCb preliminary 2011 data, 336 pb-1 LHCb-CONF-2011 -53 B 2 * B 1 B**0 B+ - First observation B 1 + B 2*+ B**+ B 0 + Fit: signal 2 BW’s for B* 2 with fixed mass difference 45. 8 Me. V for M(B*)-M(B) (PDG) 1 BW for B 1. Fix yield ratio of two B* 2 transitions to be 0. 93 0. 18 [Phys. Rev. D 64 (2001) 114004. ] Fix B 1/B 2 width to be 0. 9 0. 2 [Phys. Rev. D 53(1996) 231. ] (B 2*) = 20. 6 2. 0 Me. V/c 2 Background: WS component + 2 broad gaussians representing B 0* and B’ 1 states Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 33

B** spectroscopy BS 1 BS 2* (BS 1) = 0. 65 0. 07 Me. V/c 2 (BS 2*) = 1. 85 0. 13 Me. V/c 2 Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 34

B** spectroscopy Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 35

Charmonium-like exotics Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 36

Charmonium-like exotics Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 37

Charmonium-like exotics Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 38

Charmonium-like exotics nb Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 39

Charmonium-like exotics Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 40

Charmonium-like exotics Physical Review D 85, 091103(R) (2012) No confirmation of narrow J/ state X(4140) ; no evidence for X(4274) Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 41

Bc and b-baryons Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 42

Bc+ meson mass measurement Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 43

Bc+ cross-section Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 44

Bc+ J/ + - + mode Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 45

Bc+ J/ + - + results Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 46

Bc+ J/ + - + production Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 47

Masses of b , b LHCb-CONF-2011 -060 Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 48

Masses of b , b LHCb-CONF-2011 -060 Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque b[dsb] , b [ssb] 30 May , 2012 49

Production of Λ 0 b Λ+c - + Phys. Rev. D 84 (2011) 092001. Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 50

Λ 0 b and b in D 0 p. K- mode : preliminary Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 51

Observation of excited Λb 0 baryons First observation by LHCb, significance of 4. 9 and 10. 1 Appreciable mismatch with respect to existing relativistic quarks models, reasonable agreement with large Nc (spin-averaged) approaches. ar. Xiv: 1205. 3452 v 1 [hep-ex] 15 May 2012 Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 52

Measurements of b-hadron masses Mesons and baryons are colourless objects formed by quarks and gluons and bound by strong interaction. Masses can be compared with lattice QCD calculations. LHCb has achieved world-best measurements of the B-meson and baryon masses in exclusive modes. The momentum is calibrated with J/ + decays and verified to a relative precision of 2 10 -4 using other 2 -body decays. CDF CDF Ba. Bar Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 53

Summary on b, c spectroscopy at LHCb B**sector LHCb has access to the poorly explored B**sector, and will improve the knowledge of their properties and decays X, Y, Z states First studies of X(3872) and X(4140) demonstrate potential of LHCb to explore the exotic meson sector. Future results on larger data sets. Bc studies at LHCb Mass and cross section measured using 2010 data First observation of Bc+ J/ + - + (6. 8 ) b baryon studies at LHCb Mass and lifetime of Λb 0 using 2010 data world best measurement by LHCb Masses of b , b measured using 2011 data world best measurement by LHCb Productions of Λb 0 measured with various decay modes first observation of Λ 0 b D 0 p. K- (6. 8 ) and b D 0 p. K- (2. 6 ) Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 54

FORWARD DIMUONS Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 55

Central Exclusive Dimuon Production No backward tracks, two forward tracks, no identified photon J/ (2 s) Relative proportions c 0 , c 1, c 2 very sensitive to models that can potentially explore gluon x 2 10 -6 c 0, c 1, c 2 Previous result by CDF: PRL 102 (2009) 242001 Consistent with 42 1 pb (QED) Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 56

SOME RARE b-DECAYS AND SEARCH FOR MAJORANA NEUTRINOS Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 57

Search for B+ + + First observation of a b d l+l- decay |Vtd|/ |Vts| supression relative to b s l+lnot necessarily applies for NP models 5. 2 significance for B+ + + signal yield 25. 3 -6. 4 +6. 7 events, 1 fb-1 integrated luminosity Normalisation to B+ J/ K+ Branching ratio = (2. 4 0. 6 (stat. ) 0. 20 (syst. ) ) 10 -8 in good agreement with SM expectation 1 (1. 96 0. 21) 10 -8 Best published limit : < 6. 9 10 -8 at 90% CL by Belle Collaboration Phys. Rev. D 78 (2008) 011101 S. Hai-Zhen, L. Lin-Xia, and L. Gong-Ru, New Physics Effects on rare decays B+ + + - and B+ + + in a top quark two-higgs-doublet model, Communications in Theoretical Physics 50 (2008) 696. 1 Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 58

Search for Bs (B 0) + - + LHCb-CONF-2012 -010 Bs B 0 non-resonant window Non-resonant Bs 4µ decay highly suppressed in SM 1 , BR < 10 -10. But may be enhanced by NP due to FCNC mediated by new particles decaying into µ+ µ- pairs Using the full 1 fb-1 2011 data sample, in the non-resonant window after unblinding, one Bs µ+ µ- event and no B 0 µ+ µ- evts are observed. Expected backgrounds are : 0. 38 -0. 17 +0. 23 (0. 30 -0. 20 +0. 22 ) for Bs (B 0 ) Seven Bs J/ events observed in the resonant window (estimated BR (2. 3 0. 9) 10 -8 )) 95% CL upper limits: B (Bs µ+ µ- ) < 1. 3 10 -8 and B (B 0 µ+ µ- ) < 5. 4 10 -9 D. Melikhov and N. Nikitin, PRD 70, 114028 (2004) 2 S. Demodov and D. Gorbunov Flavor violating processes with sgoldstino pair production, ar. Xiv: 1112. 5230. 1 Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 59

Search for Majorana neutrinos at LHCb “Searches for Majorana neutrinos in B- decays” (The LHCb Collaboration) b Wa) Wu + c ar. Xiv: 1201. 5600 v 2 [hep-ex] 23 Mar 2012 N Virtual Majorana neutrino - ¯d b) Resonant neutrino production c) Also resonant production Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 60

Majorana neutrinos B- D+(*) - - a) B - D + - - B- D*+ - - No signal evidence, background from side bands BR < 6. 9 95% CL BR (B- D*+ - -) < 2. 4 10 -6 95% CL (B- 1 D + - - ) 10 -7 1 More stringent than previous Belle result , Phys. Rev. D 84 (2011) 071106 Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 61

Majorana neutrinos B- + - and B- Ds+ - No signal seen above backgrounds: Neutrino on-shell masses (m 4) have been searched for : b) m 4 Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque m 4 30 May , 2012 62

Mass and lifetime acceptance for on-shell Majorana Neutrinos Our search has ignored thus far the possibility of a finite neutrino lifetime. All sensitivity is lost for lifetimes longer than 10 -10 s to 10 -11 s. (of course this does not apply for virtual Majoranas) B- + - b) Bernardo Adeva, USC B - D s + - - B- D 0 + - - Mass dependent upper limits on BR Neutrino mass acceptance Winter Meeting IMFP-2012 Benasque 30 May , 2012 63

Summary of Majorana neutrinos b) Using B- + - - , neutrino mass dependent upper limits were established on the couplings |V 4| of a heavy Majorana N to a muon and virtual W using matrix elements from [1]. A model dependent calculation [2] was used for B- D 0 + - - , but the mode + - - is more sensitive. For the B- D+(*) - - , upper limits on the coupling cannot be extracted until there is theoretical calculation of hadronic form factor (as there is for 0 decay). [1] A. Atre, T. Han, S. Pascoli, and B. Zhang, JHEP 05 (2009) 030, ar. Xiv: 0901. 3589. [2] D. Delepine, G. Lopez Castro, and N. Quintero, Phys. Rev. D 84 (2011) 096011, ar. Xiv: 1108. 6009. Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 64

Conclusion § LHCb has shown powerful performance as a forward detector in pp collisions at s = 7 Te. V for precision b and c physics, with very good mass and proper time resolution, and excellent K/ separation : observation of asymmetries in forward production of EW bosons first observation of new resonances and decay modes great potential for exploring rare decays, including lepton flavor violation § CP-violation has been observed for the first time in D 0 and Bs mesons, and a wide range of measurements is forseen, with potential new physics discovery, both in CP-violation and very rare decays (see G. Wilkinson’s talk tomorrow) Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 65

BACKUP Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 66

Lifetime distributions B 0 and Bs B 0 → π+ π- Bs →K+ K- Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 67

Charm spectroscopy Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 68

Charm spectroscopy Feed-down states DJ →D* (D*→D , D 0) Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 69

Charm spectroscopy mmmmmmmm Bernardo Adeva, USC Feed-down states Ds. J →D*K(D*→D , D 0) Winter Meeting IMFP-2012 Benasque 30 May , 2012 70

Lifetime of Λb Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque preliminary 30 May , 2012 71

Mass of Λb Phys. Lett. B 708 (2012) 241. Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 72

Production of Λ 0 b : semi-leptonic decays Phys. Rev. D 85 (2012) 032008. Phys. Lett. B 708 (2012) 241. Bernardo Adeva, USC Winter Meeting IMFP-2012 Benasque 30 May , 2012 73