Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Jeroen van Tilburg Beauty and charm at the LHC: searches for TeV scale phenomena in flavour transitions

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Standard Model and beyond Standard Model particles

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Standard Model and beyond Standard Model particles New particles (e.g. SUSY)

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Standard Model and beyond Standard Model particles New particles (e.g. SUSY) No experimental evidence yet for new particles beyond the Standard Model.

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 LHC’s path to find new particles 1. Direct searches Produce new particles as real particles directly in pp collisions

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 LHC’s path to find new particles 1. Direct searches Produce new particles as real particles directly in pp collisions 2. Indirect searches New particles appearing as virtual particles in quantum loops.

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 LHC’s path to find new particles 1. Direct searches Produce new particles as real particles directly in pp collisions 2. Indirect searches New particles appearing as virtual particles in quantum loops.  This talk: indirect searches

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Indirect searches New particles could appear in decays of beauty and charm quarks (heavy flavours). New particles are hiding: need to look for small deviations. Need precise and clean measurements Two experimental approaches: CP violation : probe differences between matter and antimatter. Rare decays : search for decays that are (almost) impossible in the Standard Model.

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven members 16 countries 65 institutes >160 papers LHCb designed for heavy flavour physics The b in LHCb

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 A view from the cavern

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 More schematically

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Signatures of a B Typical decay length of a B ≈7 mm LHCb: good decay time resolution Relatively high mass of B. LHCb: good momentum resolution Separate signal and background LHCb: good particle identification

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 LHC: a heavy flavour factory How many beauty and charm quarks have been produced? Multiply cross section: With integrated luminosity (LHCb in ) : 3.2 fb -1  1 x bb quark pairs  2 x cc quark pairs  More beauty and charm decays than ever seen before. Look for rare decays or high precision CP violation. LHC LHCb-CONF LHCb-CONF and [arXiv: ][arXiv: ] [PLB694: ]

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Selected physics results Highlight today: o Measurement of φ s o Branching ratio B s → μ + μ − o Search for Majorana neutrinos

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Particle – antiparticle mixing Quarks always form bound state in hadrons Mesons (qq) or baryons (qqq or qqq). The quantum play-ground: neutral mesons. Example: B s (bs):

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Particle – antiparticle mixing Quarks always form bound state in hadrons Mesons (qq) or baryons (qqq or qqq). The quantum play-ground: neutral mesons. Example: B s (bs): a B s meson can oscillate into its own anti-particle!

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 B s oscillations New J. Phys. 15 (2013)

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Interference experiment If both B s and B s decay into same final state  interference! Measure time-dependent CP asymmetry Directly measures  s (Standard Model parameter) Small in SM:  s = − 0.036±0.002 * New particles could give deviation  s =  s SM +  s NP *) Prediction from CKMfitter 2011 New particles?

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Measurement of φ s Picture is consistent with Standard Model. See HFAG for averagesHFAG

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Branching ratio B s → μ + μ − B s →  +  − : sensitive probe for physics beyond SM. Very suppressed in SM. Tiny branching ratio. Branching ratio enhanced by new particles Example MSSM:

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Branching ratio B s → μ + μ −

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Branching ratio B s → μ + μ − [PRL 111, (2013)] 4.0 σ significance Compare BR(B s   +  − ) SM = (3.54 ± 0.30)x10 −9 [PRL 109, ] Small peak visible! B d Exclusion limit at 95% CL: Measurement puts strong constraints on supersymmetry models.

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Search for Majorana neutrinos Fundamental question: Are neutrinos Majorana or only Dirac? If neutrino is its own antiparticle: Lepton Flavour Violation. E.g. Same sign dimuon in B decays Neutrinoless double β decay Sensitive to neutrino-muon coupling

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Search for Majorana neutrinos Peak search in for Majorana neutrino in B −  π + μ − μ −. Branching ratio for τ N ≤ 1 ps (at 95% CL) : New result. LHCb, 3.0 fb -1, preliminary LHCB-PAPER Branching ratio limit for τ N ≤ 1 ps Preliminary

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 LuminosityLuminosity Many results shown today only done with 2011 data. Three times more data available (3 fb -1 ) and being analysed. Collect another 5 fb -1 at TeV in run 2 ( ). What then? Run 10 more years for a small reduction in uncertainty?

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 UpgradeUpgrade Current limitation: hardware trigger Main idea: Read out detector at 40 MHz. No hardware trigger, only software. Replace front-end electronics and the tracking system. Planned for the long shutdown in Running for 10 years will then give ≥ 50 fb -1 A lot of on-going activity to prepare for this upgrade. Increase integrated luminosity up to factor 10.

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 SummarySummary LHC is a beauty and charm Mega Factory! Many interesting, world-best results from LHC run 1. Most of them consistent with Standard Model. Is new physics hiding or will we see a glimpse soon? Expect many exciting results from run 2 and after upgrade. Bright future ahead of us.

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Backup slides

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Branching ratio B d,s → μ + μ − CMS finds similar numbers: LHCb+CMS combination for B s > 5 σ [LHCb-CONF ] [CMS-PAS-BPH ]

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Angular analysis of B d  K *  +  − B d   +  − K * rare decay in Standard Model. BR ≈1.0 x 10 −6 W ± is spin 1 particle, while H ± is spin 0. Modifies the angular distributions of final state particles. Sensitive to SUSY, graviton exchanges, extra dimensions… Example of SM diagram: W exchange Example of NP diagram: Charged Higgs exchange

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Angular analysis of B d  K *  +  − Measure A FB as function of invariant mass of muon pair. Zero crossing point of A FB ( q 2 ) has small theoretical (hadronic) uncertainties Four particles in final state: many more angular distributions to look at! Example: Muon forward-backward asymmetry ( A FB )

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 First measurement of zero crossing point A FB Consistent with SM value ( 3.9 – 4.4 GeV 2 /c 4 ) Angular analysis of B d  K *  +  − [JHEP 01 (2012) 107] [EPJ C41 (2005) 173] [EPJ C47 (2006) 625] LHCb, 1.0 fb − 1 [JHEP 1308 (2013) 131]

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Angular analysis of B d  K *  +  − Other observables with low theory uncertainties: Local discrepancy: 3.7 sigma Global probability (24 measurements): 0.5% Possible explanation: modified Wilson coefficient C 9. New Physics? Analyze remaining data. 3 times more data available. SM predictions from [JHEP 05 (2013) 137] [JHEP 05 (2013) 137] LHCb, 1.0 fb − 1 [PRL 111, (2013)]

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Progress in CKM matrix Flavour transitions described by CKM matrix. Knowledge of CKM matrix visualized by a unitary triangle (UT). Size of CP violation in SM defined by size of triangle. CP violation measures angles of UT ( α, β, γ, φ s )  parameters of SM

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Search for Majorana neutrinos Peak search in for Majorana neutrino in B −  π + μ − μ −. New result. LHCb, 3.0 fb-1, preliminary LHCB-PAPER Limit on coupling to heavy Majorana for τ N ≤ 1000 ps Preliminary See Atre et al.Atre et al.

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 Current limitation Hardware trigger (L0) yield levels off. Hadronic channels do not gain at higher luminosities

Beauty and charm at the LHC, Jeroen van Tilburg, FOM Veldhoven 2014 LHCb Upgrade LHCb Upgrade LoI: CERN-LHCC Integrated luminosity of order 50 fb -1 allows to measure NP effects below the % level.