Overview of LHCb results

Transcription

1 Overview of LHCb results Marcin Chrząszcz on behalf of the LHCb collaboration, Universität Zürich, Institute of Nuclear Physics, Polish Academy of Science Katowice, May / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 1/3 3

2 Flavour Physics, WHAT, WHY HOW? WHAT: Quarks and leptons exists in 6 flavours (u,c,t,d,s,b) and (e,µ, τ, ν e, ν µ, ν τ ) WHY: Flavour is the heart of SM It involves 22 from 28 free parameters, like masses mixing and CP violation Flavour physics loop processes (box and penguins) are sensitive to energy scales well beyond the ones of the accelerators, thanks to virtual contributions HOW: Compare precise theoretical predictions with precise experimental measurements LHCb, Belle, BaBar, ATLAS, CMS, NA62, BESIII, neutrinos experiments, 2 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 2/3 3

3 Searching for New Physics The fundamental questions: Why 3 generations? Why such a hierarchy structure? Stability of the Higgs vacum? Dark Matter? Baryon asymmetry of the universe? CP in SM is too small! 3 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 3/3 3

4 Searching for New Physics The fundamental questions: Why 3 generations? Why such a hierarchy structure? Stability of the Higgs vacum? Dark Matter? Baryon asymmetry of the universe? CP in SM is too small! Two ways to answer them: Direct searches: try to produce directly new real particles on-shell, but we don t know their mass or lifetime and we are limited by the center-of-mass energy of accelerator Indirect searches: study the effect of off-shell (virtual) particles within quantum loop Compare precise theoretical predictions with precise experimental measurements Not limited by the center-of-mass energy of accelerator It happened in the past: CP violation in the Kaon system: existence of b and t quarks Lack of observation of KS µµ: existence of c quark Neutral weak currents: existence of Z boson Very powerful tool! 3 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 3/3 3

5 Selected physics results: Rare Decays B s /B d µµ B d K µµ, B s ϕµµ, Λ b Λµµ Tests of lepton universalities: R k = B(B + K + µµ)/b(b + K + ee) R(D), R(D ) CP violation: CP violation in B d and B s CP violation in charm V ub 4 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 4/3 3

6 Rare decays 5 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 5/3 3

7 Tools Operator Product Expansion and Effective Field Theory H eff = 4G f 2 V V i C i (µ)o i (µ) + C }{{} i(µ)o }{{ i(µ), } left-handed right-handed i=1,2 i=3-6,8 Tree Gluon penguin i=7 Photon penguin i=9,1 i=s i=p EW penguin Scalar penguin where C i are the Wilson coefficients and O i are the corresponding effective operators Pseudoscalar penguin 6 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 6/3 3

8 B d,s µ + µ Clean theoretical prediction, GIM and helicity suppressed in the SM: B(B s µ µ + ) = (365 ± 23) 1 9 B(B µ µ + ) = (16 ± 9) 1 1 Sensitive to contributions from scalar and pesudoscalar couplings Probing: MSSM, higgs sector, etc In MSSM: B(B s µ µ + ) tg 6 β/m 4 A Theory errors dominated by the form factors! Will go down in the future 7 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 7/3 3

9 B µ + µ Results PRL 11 (213) 2181 Nov 212: First evidence 35σ for B µ + µ with 21 fb 1 Summer 213: Full data sample: 3 fb 1 Measured BF: B(Bs µ µ + ) = ( (stat)+3 1 (syst)) 1 9 4σ significance! B(B µ µ + ) < at 95% CL CMS result: PRL 111 (213) / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 8/3 3

10 LHCb+CMS Combination Nature 522 (215) 68 B(B s µ µ + ) = ( ) 1 9 B(B µ µ + ) = ( ) σ compatibility with SM! 9 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 9/3 3

11 B d K µµ JHEP, 135:137, (213) The decay of Bd K µµ has number of angular observables that are sensitive to different Wilson coefficients: C ( ) 7, C( ) 9, C( ) 1 The complete angular expression is given by: Furthermore, one can construct a form factor free observables: P 5 = S 5 F L (1 F L ) 1 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 1/3 3

12 B d K µµ results JHEP 2 (216) 14 F L 1 LHCb SM from ABSZ Likelihood fit Method of moments S 3 5 LHCb SM from ABSZ Likelihood fit Method of moments q 2 [GeV /c 4 ] q 2 [GeV 2 /c 4 ] S 4 5 LHCb SM from ABSZ Likelihood fit Method of moments S 5 5 LHCb SM from ABSZ Likelihood fit Method of moments q 2 [GeV 2 /c 4 ] q 2 [GeV 2 /c 4 ] 11 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 11/3 3

13 B d K µµ results JHEP 2 (216) 14 A FB 5 S 7 5 LHCb Likelihood fit Method of moments -5 LHCb SM from ABSZ Likelihood fit Method of moments q 2 [GeV 2 /c 4 ] q 2 [GeV 2 /c 4 ] S 8 5 LHCb Likelihood fit Method of moments S 9 5 LHCb Likelihood fit Method of moments q 2 2 [GeV /c 4 ] S 7, S 8, S 9 are zero in the SM! q 2 11 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 11/3 3 [GeV 2 /c 4 ]

14 B d K µµ results 5 P' 1 arxiv: SM from DHMV LHCb Run 1 analysis LHCb 211 analysis Belle arxiv: q 2 [GeV /c 4 ] Tension with 3 fb 1 gets confirmed! Two bins both deviate by 28 σ from SM prediction Result compatible with previous results and Belle! SM: JHEP12(214) / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 12/3 3

15 Compatibility with SM JHEP 2 (216) 14 Use EOS software package to test compatibility with SM Perform the χ 2 fit to the measured: 2 χ R(C 9 ) R(C 9 ) fit R(C 9 ) SM = 13 F L, A F B, S 3,,9 Float a vector coupling: R(C 9 ) Best fit is found to be 34 σ away from the SM SM LHCb Re (C 9 ) 13 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 13/3 3

16 BF of B K ± µµ JHEP 7 (212) 133 Despite large theoretical errors the results are consistently smaller than SM prediction 14 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 14/3 3

17 BF of B s ϕµµ JHEP9 (215) 179 Last years LHCb measurement Suppressed by f s f d Cleaner because of narrow ϕ resonance 33 σ deviation in SM in the 1 6GeV 2 bin 15 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 15/3 3

18 BF of Λ b Λµµ JHEP 6 (215) 115 Last years LHCb measurement In total 3 candidates in data set Decay not present in the low q 2 16 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 16/3 3

19 BF of Λ b Λµµ JHEP 6 (215) 115 Last years LHCb measurement In total 3 candidates in data set Decay not present in the low q 2 16 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 16/3 3

20 Angular analysis of Λ b Λµµ For the bins in which we have > 3 σ significance the forward backward asymmetry for the hadronic and leptonic system JHEP 6 (215) 115 A H F B A l F B is in good agreement with SM always above SM prediction 17 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 17/3 3

21 Lepton Universality tests 18 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 18/3 3

22 Lepton universality test Phys Rev Lett 113, (214) Does the NP couple equally to all flavours? Challenging electron analysis Migration of events modelled by MC Correct for Bremsstrahlung Take double ratio with B + J/ψK + to cancel systematics In 3fb 1, LHCb measures: R K = (stat) (syst) Consistent with SM at 26σ 19 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 19/3 3

23 More Lepton universality tests There is one other LUV decay recently measured by LHCb R(D ) = B(B D τ ν) B(B D µν) Clean SM prediction: R(D ) = 252(3), PRD (212) LHCb result: R(D ) = 336 ± 27 ± 3 HFAG average: R(D ) = 322 ± 22 4 σ discrepancy wrt SM 2 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 2/3 3

24 Explanation of anomalies arxiv: Thanks to S Descotes-Genon, LHofer, JMatias, JVirto we have a global fit to the anomalies The fit prefer a modification of C 9 Wilson coefficient with a value of C NP 9 = 1, with a significance over 4σ 21 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 21/3 3

25 Explanation of anomalies We are not there yet! There might be something not taken into account in the theory Resonances (J/ψ, ψ(2s)) tails can mimic NP effects There might be some non factorizable QCD corrections However, the central value of this effect would have to be significantly larger than expected on the basis of existing estimates DStraub, / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 22/3 3

26 Mixing induced CPV in B s Interference between B s decaying to J/ψϕ either directly or by oscillations gives rise to CP violation phase: ϕ J/ψϕ s ) In the SM ϕ s 2β s = ( ) rad, where β s = arg ( VtsV tb V csv cb At leading order same phase is expected Bs D s D s and B J/ψππ NP can enter in the Bs mixing! Measured by simultaneous fit to Bs and B s decay rates: 23 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 23/3 3

27 Mixing induced CPV in B s PRL 114, 4181 (215) Unbinned maximum likelihood fit (time, mass, angles, initial flavour): ϕ s = 58 ± 49 ± 6 rad Γ s = (Γ L + Γ H )/2 = 663 ± 27 ± 15 ps 1 Γ s = Γ L Γ H = 85 ± 91 ± 32 ps 1 Combined with Bs J/ψππ: ϕ s = 1 ± 39 rad 24 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 24/3 3

28 Mixing induced CPV in B s HFAG webpage LHCb is dominating the world average! ϕ HFAG s = 34 ± 33 Compatible with SM, but there is still plenty room for NP! Penguin pollution constrained from B J/ψρ and Bs J/ψ K 25 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 25/3 3

29 V ub Nature Physics 11, (215) Since a long time the smallest of the CKM matrix elements V ub has been determined in two ways: inclusively: b ulν, V ub = (441 ± ) 1 3 exclusively: B πlν, V ub = (328 ± 29) σ tensions! LHCb perspectively enters the game with baryons decay: Λ b pµν where R F F is a ratio of form factors, that can be calculated using lattice QCD [arxiv: ] 26 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 26/3 3

30 V ub Nature Physics 11, (215) V ub = (327 ± 15 ± 16 ± 6(V cb )) 1 3 LHCbs measurement makes the discrepancy larger and is spot on the exclusive B-factories results Disfavor NP models with significant right handed current Debatable world averages, depending on the input used (theory, BR of control mode, ) 27 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 27/3 3

31 CP violation in charm LHCb-PAPER , PLB 753 (216) 412 The A CP asymmetry is defined as: A CP (D f) = Γ(D f) Γ( D f) Γ(D f) + Γ( D f), f = K + K, π + π New world average: a ind CP = (56 ± 4)% a dir CP = ( 137 ± 7)% Results consistent with no CPV at 65 % CL 28 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 28/3 3

32 Conclusions Flavour physics is still playing an important role for hunting new physics! Anomalies in the electroweak penguin and lepton universality combine to over 4σ significance discrepancy for NP The dominant anomaly was recently confirmed by Belle experiment! Most precise measurements of CP violations in B s system First V ub determination from baryon decays! Stay tuned as there are plenty of more results in the pipe line! 29 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 29/3 3

33 Thank you for the attention! 3 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 3/3 3

34 Backup 31 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 31/3 3

35 Theory implications 32 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 32/3 3

36 If not NP? How about our clean P i observables? The QCD cancel as mentioned only at leading order Comparison to normal observables with the optimised ones 33 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 33/3 3

37 Transversity amplitudes One can link the angular observables to transversity amplitudes J 1s = (2 + β2 l ) 4 [ A L 2 + A L 2 + A R 2 + A R 2] + 4m2 l (A ) q 2 Re L AR L + A AR, ] J 1c = A L 2 + A R 2 + 4m2 l [ A q 2 t 2 + 2Re(A L AR ) + β 2 l A S 2, J 2s = β2 l 4 J 3 = 1 2 β2 l [ A L 2 + A L 2 + A R 2 + A R 2], J 2c = β 2 l [ A L 2 + A R 2], [ A L 2 A L 2 + A R 2 A R 2] [ ], J 4 = 1 β 2 l Re(A L AL R + A AR ), 2 J 5 = 2β l [Re(A L AL R A AR ) m l Re(A L q 2 A S + AR AS )], ] J 6s = 2β l [Re(A L AL R A AR m l ), J 6c = 4β l Re(A L q 2 A S + AR AS ), J 7 = 2β l [Im(A L AL R A AR ) + m l ] Im(A L q 2 A S AR AS )), J 8 = 1 [ ] [ ] β 2 l Im(A L AL R + A AR ), J 9 = β 2 l Im(A L L A + AR R A ), 2 34 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 34/3 3

38 Link to effective operators So here is where the magic happens At leading order the amplitudes can be written as (soft form factors): [ A L,R A L,R A L,R = 2Nm B (1 ŝ) (C eff 9 + C eff 9 ) (C 1 + C 1 ) + 2 ˆm b ŝ ] (Ceff 7 + C eff 7 ) ξ (E K ) [ ] = 2Nm B (1 ŝ) (C eff 9 C eff 9 ) (C 1 C 1 ) + 2 ˆm b ŝ (Ceff 7 C eff 7 ) ξ (E K ) [ ] = Nm B(1 ŝ) 2 ŝ (C eff 9 C eff 9 ) (C 1 C 1 2 ˆm ) + 2 ˆm b(c eff 7 C eff 7 ) ξ (E K ), K where ŝ = q 2 /m 2 B, ˆm i = m i /m B The ξ, are the form factors 35 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 35/3 3

39 Link to effective operators So here is where the magic happens At leading order the amplitudes can be written as (soft form factors): [ A L,R A L,R A L,R = 2Nm B (1 ŝ) (C eff 9 + C eff 9 ) (C 1 + C 1 ) + 2 ˆm b ŝ ] (Ceff 7 + C eff 7 ) ξ (E K ) [ ] = 2Nm B (1 ŝ) (C eff 9 C eff 9 ) (C 1 C 1 ) + 2 ˆm b ŝ (Ceff 7 C eff 7 ) ξ (E K ) [ ] = Nm B(1 ŝ) 2 ŝ (C eff 9 C eff 9 ) (C 1 C 1 2 ˆm ) + 2 ˆm b(c eff 7 C eff 7 ) ξ (E K ), K where ŝ = q 2 /m 2 B, ˆm i = m i /m B The ξ, are the form factors Now we can construct observables that cancel the ξ form factors at leading order: P 5 J 5 + = J 5 2 (J2 c + J 2 c)(j 2 s + J 2 s) 35 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 35/3 3

40 Mass modelling The signal is modelled by a sum of two Crystal-Ball functions with common mean The background is a single exponential The base parameters are obtained from the proxy channel: B d J/ψ(µµ)K All the parameters are fixed in the signal pdf Scaling factors for resolution are determined from MC In fitting the rare mode only the signal, background yield and the slope of the exponential is left floating We found 624 ± 3 candidates in the most interesting [11, 6] GeV 2 /c 4 region and 2398 ± 57 in the full range [11, 19] GeV 2 /c 4 Candidates / 11 MeV/c LHCb B K * µ + µ m(k + π µ + µ ) [MeV/c 2 ] The S-wave fraction is extracted using a LASS model 36 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 36/3 3

41 Detector acceptance Detector distorts our angular distribution We need to model this effect 4D function is used: ϵ(cos θ l, cos θ k, ϕ, q 2 ) = P i (cos θ l )P j (cos θ k )P k (ϕ)p l (q 2 ), ijkl where P i is the Legendre polynomial of order i We use up to 4 th, 5 th, 6 th, 5 th order for the cos θ l, cos θ k, ϕ, q 2 The coefficients were determined using Method of Moments, with a huge simulation sample The simulation was done assuming a flat phase space and reweighing the q 2 distribution to make is flat 37 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 37/3 3

42 Control channel We tested our unfolding procedure on B J/ψK The result is in perfect agreement with other experiments and our different analysis of this decay Candidates / 53 MeV/c LHCb B J/ψ K * Candidates / 1 MeV/c 2 6 LHCb * B J/ψ K m(k + π µ + µ ) [MeV/c 2 ] m(k + π ) [GeV/c 2 ] 38 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 38/3 3

43 The columns of New Physics 39 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 39/3 3

44 B d K µµ results JHEP 2 (216) 14 In the maximum likelihood fit one could weight the events accordingly to the 1 ε(cos θ l, cos θ k, ϕ, q 2 ) Better alternative is to put the efficiency into the maximum likelihood fit itself: N L = ϵ i (Ω i, qi 2 )P(Ω i, qi 2 )/ ϵ(ω, q 2 )P(Ω, q 2 )dωdq 2 i=1 Only the relative weights matters! The Procedure was commissioned with TOY MC study Use Feldmann-Cousins to determine the uncertainties Angular background component is modelled with 2 nd order Chebyshev polynomials, which was tested on the side-bands S-wave component treated as nuisance parameter CL 1 CL 1 CL LHCb 4 < q 2 < 6 GeV 2 /c 4 2 LHCb 11 < q 2 < 25 GeV 2 /c 4 2 LHCb 11 < q 2 < 125 GeV 2 /c A FB P 1 5 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 4/3 3

45 Maximum likelihood fit - Results F L LHCb SM from ABSZ S 3 5 LHCb SM from ABSZ q 2 [GeV /c 4 ] q 2 [GeV 2 /c 4 ] S 4 5 LHCb S 5 5 LHCb SM from ABSZ SM from ABSZ q 2 [GeV 2 /c 4 ] q 2 [GeV 2 /c 4 ] SM: EurPhysJ C75 (215) no8, / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 41/3 3

46 Maximum likelihood fit - Results A FB 5 S 7 5 LHCb -5 LHCb SM from ABSZ q 2 [GeV 2 /c 4 ] q 2 [GeV 2 /c 4 ] S 8 5 LHCb S 9 5 LHCb q 2 [GeV 2 /c 4 ] q 2 [GeV 2 /c 4 ] SM: EurPhysJ C75 (215) no8, / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 41/3 3

47 Method of moments See PhysRevD91(215)11412, FBeaujean, MChrzaszcz, NSerra, D van Dyk for details The idea behind Method of Moments is simple: Use orthogonality of spherical harmonics, f j ( Ω ) to solve for coefficients within a q 2 bin: f i ( Ω )f j ( Ω ) = δ ij ( ) 1 d 3 (Γ + M i = Γ) d(γ + Γ)/dq 2 d f i( Ω )dω Ω Don t have true angular distribution but we sample it with our data Therefore: and M i Mi ˆM i = 1 e ω e ω ef i( Ω e) The weight ω accounts for the efficiency Again the normalization of weights does not matter e 42 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 42/3 3

48 Amplitudes method Fit for amplitudes as (continuous) functions of q 2 in the region: q 2 [116] GeV 2 /c 4 Needs some Ansatz: A(q 2 ) = α + βq 2 + γ q 2 The assumption is tested extensively with toys Set of 3 complex parameters α, β, γ per vector amplitude: L, R,,,, R, I = 36 DoF Scalar amplitudes: +4 DoF Symmetries of the amplitudes reduces the total budget to: 28 The technique is described in JHEP6(215)84, U Egede, M Patel, KA Petridis Allows to build the observables as continuous functions of q 2 : At current point the method is limited by statistics In the future the power of this method will increase Allows to measure the zero-crossing points for free and with smaller errors than previous methods 43 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 43/3 3

49 Amplitudes - results A FB 5 LHCb Amplitude fit Likelihood fit Method of moments S 5 5 LHCb Amplitude fit Likelihood fit Method of moments q 2 [GeV /c 4 ] q 2 [GeV /c 4 ] S 4 5 LHCb Amplitude fit Likelihood fit Method of moments Zero crossing points: q 2 [GeV /c 4 ] q (S 4 ) < 265 q (S 5 ) [249, 395] q (A F B) [34, 487] at 95% CL at 68% CL at 68% CL 44 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 44/3 3

50 B µ + µ searches PRL 111 (213) 1185 Background rejection power is a key feature of rare decays use multivariate classifiers (BDT) and strong PID Normalize the BF to B + J/ψ(µµ)K + and B Kπ 45 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 45/3 3

51 Tetra&Petraquarks Idea of this multi quark states started in the 196s: Searches for years and many discoveries not confirmed 46 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 46/3 3

52 Z(443) Z(443) special tetraquark candidate,because charged: cannot be a c c state! Belle discovered it in B Υ(2S)Kπ, with evidence of J P = 1 + [PRD 88 (213) 7426] Using method of moments, Babar claimed they do not need the Z(443) to described their data [PRD 79 (29) 1121] LHCb reproduced BaBar moments analysis with the full Run1 sample (3 fb 1 ) and clearly something mote was needed to describe the data [PRL 112, 2222 (214)] 47 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 47/3 3

53 Z(443) LHCb, PRL 112, 2222 (214) LHCb unbinned amplitude analysis of B ψ(2s)k + π, m = 4475 ± MeV/c2, Γ = 172 ± MeV/c 2 J P is confirmed to be 1 + and Argand plot shows the typical pattern for resonances Minimal quark content ccdu 48 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 48/3 3

54 Pentaquarks in Λ b J/ψpK [LHCb, PRL 115 (215) 721] Λ b J/ψpK was studied initially for a precise Λ b lifetime Close look at the Dalitz: m(kp) m(j/ψp) m(kp) has a rich structure of excited Λ states m(j/ψp) has something inside! 49 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 49/3 3

55 Pentaquarks in Λ b J/ψpK [LHCb, PRL 115 (215) 721] Super complex fit needed to describe the data: 5 decay angles, 14 possible Λ resonances for m(kπ) and two brand new pentaquarks for m(j/ψp): P c (438) + : 438 ± 8 ± 29 MeV/c 2, Γ = 25 ± 18 ± 86 MeV/c 2, J P = 3 2 P c(445) + : 4449, 8 ± 17 ± 25 MeV/c 2, Γ = 39 ± 5 ± 19 MeV/c 2, J P = / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 5/3 3

56 Pentaquarks in Λ b J/ψpK [LHCb, PRL 115 (215) 721] Angrad plots show the phase motion for the resonances The P c(438) has one point off by a 2σ The interference patterns confirm the opposite parities The significance was evaluated with a TOY MC: P c (438) + : 9σ P c(445) + : 12σ The states are consistent with ccuud 51 / Marcin Chrząszcz (Universität Zürich, IFJ PAN) Overview of LHCb results 51/3 3