B-physics and other anomalies as hints for new physics

Transcription

1 B-physics and other anomalies as hints for new physics Julian Heeck IPP15, Tehran, Iran Based on work in collaboration with Andreas Crivellin, Giancarlo D Ambrosio, Peter Stoffer, Martin Holthausen, Werner Rodejohann, and Yusuke Shimizu.

2 Current flavor anomalies: Lepton flavor violation in Brout Englert Higgs boson decay : CMS [ ]: 2.4σ: ( BR() = ATLAS [ ]: 1.2σ: ) %. BR() = (0.77 ± 0.62) %. 2.6σ combined. Requires couplings beyond the SM: L y µτ µ L τ R h y τµτ L µ R h + h.c. with yµτ 2 + y τµ By itself not in conflict with τ µγ etc. 1 Go-to explanation: extended scalar sector, e.g. (type-iii) 2HDM. 2 1 Blankenburg, Ellis, Isidori, ; Harnik, Kopp, Zupan, ; Davidson, Verdier, ; Kopp, Nardecchia, Campos, Hernandez, Päs, Schumacher, ; Celis, Cirigliano, Passemar, ; Aristizabal Sierra, Vicente, ; J.H., Holthausen, Rodejohann, Shimizu, ;... Julian Heeck (ULB) Recent flavor anomalies 1 / 27

3 Current flavor anomalies: Rare flavor changing decays B K ll at loop level in SM. Branching ratios of order b γ, Z s l l W ν W l l B W K B K q q B = B 0 for q = d. B = B for q = u. B = B s 0 for q = s (and K φ). Julian Heeck (ULB) Recent flavor anomalies 2 / 27

4 Current flavor anomalies: LHCb [ ]: 2.6σ lepton non-universality: R(K) B+ K + µµ B + K + ee = ± 0.036, SM prediction R(K) = 1 ± O(10 4 ) [Bobeth, Hiller, Piranishvili, ]. (Comes from smaller µµ rate.) LHCb [ ]: 3.5σ too small differential branching fraction B 0 s φµ + µ K + K µ + µ, confirming 1/fb analysis [ ]. LHCb [LHCb-CONF ]: 3.7σ deviation in angular observable P 5 of B 0 K µµ K + π µµ, confirming 1/fb analysis [ ]. Julian Heeck (ULB) Recent flavor anomalies 3 / 27

5 Global fit for Flavor anomalies Global fit 3 with effective Hamiltonian ( H eff = 4G F V tb Vts α EM 2 4π j=9,10 Cj ll Oj ll + C j ll O j ll ) + h.c., with O9 ll = [ sγ µ P L b] [ lγ ] ] µl, O10 ll = [ sγ µ P L b] [ lγ µγ 5 l, O 9 ll = [ sγ µ P R b] [ lγµl ] ], O 10 ll = [ sγ µ P R b] [ lγµγ 5 l, to all B X µ + µ, B X γ observables (but not R(K) etc.): 3.7σ : C NP 9 = 1.07 ± 0.25 (= 25%C SM 9 ). 3 Altmannshofer, Straub, , Similar results by Descotes-Genon et al.; Hurth, Mahmoudi, Neshatpour, ;... Julian Heeck (ULB) Recent flavor anomalies 4 / 27

6 Global fit for Flavor anomalies Global fit 3 with effective Hamiltonian ( H eff = 4G F V tb Vts α EM 2 4π j=9,10 Cj ll Oj ll + C j ll O j ll ) + h.c., with O9 ll = [ sγ µ P L b] [ lγ ] ] µl, O10 ll = [ sγ µ P L b] [ lγ µγ 5 l, O 9 ll = [ sγ µ P R b] [ lγµl ] ], O 10 ll = [ sγ µ P R b] [ lγµγ 5 l, to all B X µ + µ, B X γ observables (but not R(K) etc.): 3.7σ : C NP 9 = 1.07 ± 0.25 (= 25%C SM 9 ). Include e + e (R(K)): 4.3σ for C µµ 9. Need (sγ α P L b)(µγ α µ)/(35 TeV) 2, but no electrons. 3 Altmannshofer, Straub, , Similar results by Descotes-Genon et al.; Hurth, Mahmoudi, Neshatpour, ;... Julian Heeck (ULB) Recent flavor anomalies 4 / 27

7 Prel. EPS2015 Flavor anomalies Current flavor anomalies: Lepton non-universality in B decays ν R(D ( ) ) B D ( ) τ ν B D ( ) l ν. b W c l Combination of BaBar, Belle, and LHCb R(D) exp = ± 0.047, R(D ) exp = ± 0.021, compared to SM prediction (e.g. [Fajfer, Kamenik, Nisandzic, ]) R(D) SM = ± 0.017, R(D ) SM = ± 0.003, 3.9σ combined (HFAG). Confirms earlier results by BaBar & Belle. R(D*) B 0 D + d BaBar, PRL109,101802(2012) Belle, arxiv: LHCb, arxiv: Average SM prediction R(D) d 2 χ = 1.0 HFAG P(χ 2 ) = 55% Julian Heeck (ULB) Recent flavor anomalies 5 / 27

8 Wilson coefficients for Possible new physics explanation of B D ( ) τν by charged Higgs. Relevant effective Hamiltonian H eff = C qb SM Oqb SM + C qb R Oqb R O cb SM = cγµp Lb τγ µp L ν τ, + C qb L Oqb L, OL,R cb = cp L,Rb τp L ν τ. cb cb C R CSM Need e.g. C cb R = 0 and C cb L [ R(D ) C cb R R(D = R ) SM 1.2 C cb SM. C cb L C cb SM (B τν depends on ub couplings.) ] C cb R C cb L C cb SM C cb cb L C SM Can not explain R(D) and R(D ) in type-ii 2HDM, but works in general type III [Crivellin, Greub, Kokulu, , ], or modified type X (also resolving muon s magnetic moment anomaly) [J.H., Crivellin, Stoffer, ]. Julian Heeck (ULB) Recent flavor anomalies 6 / 27

9 A model for J.H., M. Holthausen, W. Rodejohann, Y. Shimizu, Nucl. Phys. B896 (2015) , [arxiv: ]. Julian Heeck (ULB) Recent flavor anomalies 7 / 27

10 Flavor violating Higgs decays For 2.4σ effect BR() = ( ) % need L y µτ µ L τ R h y τµ τ L µ R h + h.c. with y µτ 2 + y τµ Go-to explanation: extended scalar sector, e.g. 2HDM. 4 Lepton flavor violation connection to flavor symmetries? 5 Non-abelian symmetries A 4 or S 4 have at least 3HDM. Predict BR(h eτ) BR(). 4 de Lima, Machado, Matheus, do Prado, ; Dorsner et al, Campos, Hernández, Päs, Schumacher, ; J.H., Holthausen, Rodejohann, Shimizu, Julian Heeck (ULB) Recent flavor anomalies 8 / 27

11 Flavor violating Higgs decays For 2.4σ effect BR() = ( ) % need L y µτ µ L τ R h y τµ τ L µ R h + h.c. with y µτ 2 + y τµ Go-to explanation: extended scalar sector, e.g. 2HDM. 4 Lepton flavor violation connection to flavor symmetries? 5 Non-abelian symmetries A 4 or S 4 have at least 3HDM. Predict BR(h eτ) BR(). Here: take abelian symmetry. Lepton numbers in h µτ, µ τ: L e = 0 = (L µ + L τ ), but (L µ L τ ) = ±2. 4 de Lima, Machado, Matheus, do Prado, ; Dorsner et al, Campos, Hernández, Päs, Schumacher, ; J.H., Holthausen, Rodejohann, Shimizu, Julian Heeck (ULB) Recent flavor anomalies 8 / 27

12 Gauged U(1) Lµ L τ Flavor anomalies flavor symmetry L µ L τ well known symmetry: Current j α = µγ α µ τγ α τ + ν µ γ α P L ν µ ν τ γ α P L ν τ. Anomaly free in SM. 6 Light Z could resolve (g 2) µ anomaly. 7 Good zeroth order approximation to neutrino mixing with quasi-degenerate masses (m 1,2,3 1 ev and β = π/2): M ν = U PMNS diag(m 1, m 2, m 3)UPMNS T ev 0 0 L µ L τ L µ L τ gives θ 23 = π/4 and θ 13 = He, Joshi, Lew, Volkas, PRD 1991; Foot, MPLA Altmannshofer, Gori, Pospelov, Yavin, PRL 2014, Binetruy, Lavignac, Petcov, Ramond, NPB 1997; Bell, Volkas, PRD 2001; Choubey, Rodejohann, EPJC Julian Heeck (ULB) Recent flavor anomalies 9 / 27

13 L µ L τ in a 2HDM Flavor anomalies 2HDM: Φ 1 2, Φ 2 0 under U(1) Lµ L τ. 9 Plus scalar singlet S 1 and three ν R (0, 1, 1) for seesaw. S S generates M R for valid PMNS, M Z /g = S, and S 2 Φ 2 Φ 1 m3 2Φ 2 Φ 1. small VEV Φ 1 induced! ( large tan β region.) Lepton Yukawa couplings: Y l2 = diag(y e, y µ, y τ ), Y l1 = ξ τµ 0 Gauge symmetry sets all other LFV couplings zero! Coupling hµτ now generated by scalar mixing and lepton mixing. 9 J.H., Rodejohann, PRD 2011, see Dutta, Joshipura, Vijaykumar, PRD 1994, for Le L µ,τ. 10 J.H., Holthausen, Rodejohann, Shimizu, Julian Heeck (ULB) Recent flavor anomalies 10 / 27

14 Charged lepton masses Diagonalization of M e requires small µ R τ R rotation SM-like scalar h couples y h diag(m e, m µ, m τ ) cα vs β } {{ } type-i 2HDM Z couples to (e, µ, τ) via P L + 1 s R sin θ R v m τ ξ τµ 2 cos β. s R m τ v cos(α β) c β s β cos 2θ R sin 2θ R c R s R sin 2θ R P R, cos 2θ R leads to τ 3µ; need θ R (M Z /g /1 TeV) 2. Only LFV in µ τ sector, quarks and electrons save! Julian Heeck (ULB) Recent flavor anomalies 11 / 27

15 Flavor anomalies CMS 2.4σ excess in for yτµ h = m τ β) cos(α c R s R v c β s β! c β s R 1 and ξ τµ c α β (slightly) modified h ττ. Otherwise just type-i 2HDM. Expect τ 3µ (see later). resolved. CMS allowed regions for h l i l j : BR h l i l j Σ h ΤΤ 1Σ h ΜΤ 2Σ h ΜΤ ΤΤ ΜΤ R solid: tan β = 3, cos(α β) = 0.3, dashed: tan β = 10, cos(α β) = 0.2, dotted: tan β = 20, cos(α β) = 0.2. J.H., Holthausen, Rodejohann, Shimizu, ΜΜ Julian Heeck (ULB) Recent flavor anomalies 12 / 27

16 A model for J.H., A. Crivellin, G. D Ambrosio, Phys. Rev. Lett. 114 (2015) [arxiv: ]; Phys. Rev. D91 (2015), , [arxiv: ]. Julian Heeck (ULB) Recent flavor anomalies 13 / 27

17 model building For 4.3σ improvement, need (sγ α P L b)(µγ α µ)/(35 TeV) 2, no coupling to electrons. Obvious solution: flavor-non-universal Z. 11 Perfect candidate: U(1) Lµ L τ (remember?). Just need flavor- changing coupling to quarks: via heavy vector-like quarks, 12 via an additional scalar doublet Altmannshofer, Straub, , ; Gauld, Goertz, Haisch, , ; Buras, Girrbach et al., , ; Aristizabal Sierra, Staub, Vicente, ; Crivellin et al., ; Celis et al., Altmannshofer, Gori, Pospelov, Yavin, PRD 2014, ; J.H., Crivellin, D Ambrosio, PRL 2015, J.H., Crivellin, D Ambrosio, PRD 2015, Julian Heeck (ULB) Recent flavor anomalies 14 / 27

18 model building For 4.3σ improvement, need (sγ α P L b)(µγ α µ)/(35 TeV) 2, no coupling to electrons. Obvious solution: flavor-non-universal Z. 11 Perfect candidate: U(1) Lµ L τ (remember?). Just need flavor- changing coupling to quarks: via heavy vector-like quarks, 12 backup slides. via an additional scalar doublet. 13 here. 11 Altmannshofer, Straub, , ; Gauld, Goertz, Haisch, , ; Buras, Girrbach et al., , ; Aristizabal Sierra, Staub, Vicente, ; Crivellin et al., ; Celis et al., Altmannshofer, Gori, Pospelov, Yavin, PRD 2014, ; J.H., Crivellin, D Ambrosio, PRL 2015, J.H., Crivellin, D Ambrosio, PRD 2015, Julian Heeck (ULB) Recent flavor anomalies 14 / 27

19 without vector-quarks Instead of vector-like quarks with ad-hoc structure, extend L µ L τ to Q = (L µ L τ ) a(b 1 + B 2 2B 3 ) with a Q. with two scalar doublets Φ 1 a, Φ 2 0 and some singlets. y11 d y12 d 0 0 ξ db Y d2 = y21 d y22 d, Y d1 = 0 0 ξ sb y d 33 L µ L τ in lepton sector. Cabibbo angle & Kaon mixing constraints. Mixing of third quark generation by Φ 1 induces Z bs coupling. (Later: introduce third doublet Φ 3 2 to induce.) Julian Heeck (ULB) Recent flavor anomalies 15 / 27

20 Flavor violating couplings Diagonalization of quark mass matrices (focus on down quarks): ( ) ( d cos α cos(α β) v sin β md d ξd P R d h d sin α 2 sin β v sin β md d +i d ( m D d v tan β 1 2 sin β ξd ) P R d A ū sin(α β) ξd 2 sin β ( 2 v tan β VmD d 1 sin β V ξ d Type-I 2HDM plus perturbations specified by CKM: 0 0 V ξ d V 2 m b tdv tb Y d1 0 0 VtsV tb. cos β v V tb 2 ) P R d H ) P R d H +. Z couplings: Γ dl a V td V tsv td V tb V td V td Vts V ts 2 1 V 3 tb Vts V td V tb V ts V tb V tb 2 1 3, Γ dr a Julian Heeck (ULB) Recent flavor anomalies 16 / 27

21 Flavor anomalies Dominant off-diagonal: Z bs. b µ Structure perfect for : Z ( ) ( ) 2 C µµ a 3TeV 9 1/3 m Z /g, s Γ dl 23 µ C ee 9 = C ll 9 = C ll 10 = C ll 10 = a < 1 to satisfy B s mixing. b Z b a s Γ dl 23 Γ dl 23 M 12 /M SM 12 a 2 g 2 /m 2 Z. s m Z' g' TeV anomalies resolved! Julian Heeck (ULB) Recent flavor anomalies 17 / 27

22 LHC constraints Flavor anomalies Z couples to first-gen. quarks direct detection via pp Z µ + µ. For m t m Z < 2m νr : BR(Z µµ) and a 2, ee : µµ : ττ : uu : dd : ss : cc : bb : tt =0 : 1 : 1 : a2 3 : a2 3 : a2 3 : a2 3 : 4a2 3 : 4a2 3. Can rescale B L limits from ATLAS [ ]. Flavor violating decays Z bs suppressed. g' solid: a 1 2 dashed: a 1 3 C 9 ΜΜ 2Σ & Bs mixing ATLAS 95 CL C 9 ΜΜ 2Σ m Z' TeV Look forward to new LHC run! Julian Heeck (ULB) Recent flavor anomalies 18 / 27

23 Add third scalar doublet for Put in third scalar doublet Φ 3 2 for τ 3µ: BR() sin 2 θ R cos 2 (α β) tan 2 β: 0.05 cos Α 23 Β , a 1 3 h µ 0.04 τ BR(τ 3µ) sin 2 θ R g 4 /m 4 Z : µ µ Z sin Θ R µ Correlation: BR(τ 3µ) τ µµ (C 9 ) 2 BR() a 2 tan 2. β m Z' g' TeV At 2σ predict: BR(τ 3µ) (10/ tan β) 2. Julian Heeck (ULB) Recent flavor anomalies 19 / 27

24 Partial summary Flavor anomalies Tantalizing hints for new physics in flavor sector: at 2.6σ, plus R(K) at 4.3σ (sγ α P L b)(µγ α µ)/(35 TeV) 2. New physics explanation: U(1) Lµ L τ gauge symmetry. Flavor non-universal. Good for quasi-degenerate neutrinos. Z couplings to quarks can give C µµ 9 for. Z qq via mixing with vector-like quarks. Z qq via new scalar doublet type-i 2HDM. Z at LHC. New doublet Φ 2 gives (L µ L τ ) decay via mixing. Always BR(τ 3µ) (C µµ 9 ) 2 BR()/ tan 2 β. Julian Heeck (ULB) Recent flavor anomalies 20 / 27

25 Partial summary Flavor anomalies Tantalizing hints for new physics in flavor sector: at 2.6σ, plus R(K) at 4.3σ (sγ α P L b)(µγ α µ)/(35 TeV) 2. New physics explanation: U(1) Lµ L τ gauge symmetry. Flavor non-universal. Good for quasi-degenerate neutrinos. Z couplings to quarks can give C µµ 9 for. Z qq via mixing with vector-like quarks. Z qq via new scalar doublet type-i 2HDM. Z at LHC. New doublet Φ 2 gives (L µ L τ ) decay via mixing. Always BR(τ 3µ) (C µµ 9 ) 2 BR()/ tan 2 β. H + coupling too small to also explain B D ( ) τ ν/ B D ( ) l ν. Julian Heeck (ULB) Recent flavor anomalies 20 / 27

26 A model for J.H., A. Crivellin, P. Stoffer, arxiv: Julian Heeck (ULB) Recent flavor anomalies 21 / 27

27 Modified type-x 2HDM Lepton-specific 2HDM (type X): L Y = Q L Y u Φ2 u R Q L Y d Φ 2 d R L L Y l Φ 1 e R + h.c. Add breaking terms for more freedom (type X type III): L Y = Q L ξ u Φ1 u R Q L ξ d Φ 1 d R L L ξ l Φ 2 e R + h.c. For large tan β (ε l L L ξl L R etc.): Γ hlr q i q j 1 2 ( mqi v δ ij cos α ε q ij sin α ), Γ HLR q i q j 1 2 ( mqi v δ ij sin α + ε q ij cos α ), Γ H+ LR u i d j V ij ε d j j, ΓH+ RL u i d j Γ hlr sin α tan β l f l i 2 Γ ALR l f l i i tan β 2 ( mli ( mli v v δ fi ε l fi δ fi ε l fi ε l 33 > mτ /v flips sign of coupling. ε u j i V j j, ), Γ HLR cos α tan β l f l i 2 ), Γ H+ LR ν f l i tan β ( mli ( mli v δ fi ε l fi v δ fi ε l fi ). ), Julian Heeck (ULB) Recent flavor anomalies 22 / 27

28 Modified type-x 2HDM To generate and, use structure ε d = 0, ε u = , ε l = Easily resolve R(D ( ) ) using ε u tan Β GeV 2 2 m H u Ε 32 m H GeV If H (or A) are light, this induces t Hc, followed by H ττ GeV 2 tanβ m H 2 Br t ch GeV 2 tanβ m H GeV 2 tanβ m H u Ε Julian Heeck (ULB) Recent flavor anomalies 23 / 27

29 Why light H or A? Flavor anomalies Grandmother of anomalies: magnetic moment of muon (g 2) µ, at 3σ. Light A in type-x 2HDM can resolve (g 2) µ using Barr Zee diagram. 14 γ τ H 0 k γ µ 14 Broggio et al, ; Wang, Han, ; Chun, Kang, Takeuchi, Tsai, Julian Heeck (ULB) Recent flavor anomalies 24 / 27

30 Last anomaly... Flavor anomalies Problem: Leads to wrong τ lνν rates! [Krawczyk, Temes, hep-ph/ ; Abe, Sato, Yagyu, ] 0.6 Define 0.4 l BR(τ lνν)exp BR(τ lνν) SM e Μ then µ is 2.4σ above SM expectation. Relevant for Michel parameter η: z 0.0 Η z v 2 LR H+ m 2 Γν τ τ Γ LR H+ ν µµ. H For type-x: δg negative and z positive. Negative z possible for ε l 33 > mτ /v! g Flip τ coupling of A and H light H resolves (g 2) µ and τ µνν. Julian Heeck (ULB) Recent flavor anomalies 25 / 27

31 vs. (g 2) µ Light H resolves (g 2) µ and τ µνν, H + resolves R(D ( ) ). Using ε l 32, can we also get? Julian Heeck (ULB) Recent flavor anomalies 26 / 27

32 vs. (g 2) µ Light H resolves (g 2) µ and τ µνν, H + resolves R(D ( ) ). Using ε l 32, can we also get? No, large τ µγ. Same Barr Zee diagrams for (g 2) µ and τ µγ. m H [GeV] tan(β) = 50 τ μγ and h μτ (2σ) 50 Δa μ (2σ) Δa μ (1σ) m A [GeV] Can explain either (g 2) µ or together with R(D ( ) ) in our 2HDM. Julian Heeck (ULB) Recent flavor anomalies 26 / 27

33 Summary Flavor anomalies Tantalizing hints for new physics in flavor sector: Lepton flavor violation: at 2.6σ. 2HDM? Lepton flavor non-universality: R(K) at 2.6σ. (plus R(K)) at 4.3σ. Flavored Z? Lepton flavor non-universality: R(D ( ) ) at 3.9σ. Charged scalar of 2HDM? Magnetic moment: (g 2) µ at 3σ. Light neutral scalar of 2HDM? Wait for new data, new calculations, and new physics. Julian Heeck (ULB) Recent flavor anomalies 27 / 27

34 Vector-like quarks for Lµ Lτ at LHC Backup Julian Heeck (ULB) Recent flavor anomalies 28 / 27

35 New physics vs. QCD in Vector-like quarks for Lµ Lτ at LHC Check C 9 in B K µ + µ as function of µµ mass q 2 : New physics flat. Hadronic effect not flat. NP Re(C 10 ) Re(C NP 9 ) Altmannshofer, Straub, Inconclusive as of yet. If it s QCD (non-factorizable charm loop), it s much larger than expected! Julian Heeck (ULB) Recent flavor anomalies 29 / 27

36 Vector-like quarks for Vector-like quarks for Lµ Lτ at LHC Again singlet scalar S 1 under U(1) Lµ L τ and three ν R for seesaw. Q L (U L, D L ), D c R, U c R and partners Q R, D c L, Ũ c L with L µ L τ = 1: j=1 m Q Q L QR + m D DL D R + m U Ũ L U R + h.c. Yukawas 3 ( ) 3 ( ) S DR Y Q j P L d j + ŨRY Q j P L u j + S DL Yj D P R d j + ŨLYj U P R u j + h.c. j=1 induce mixing with SM quarks and Z couplings 15 with Γ dr ij g ( di γ µ P L d j Z µγ dl ij v 2 Φ 2m 2 D + d ) i γ µ P R d j Z µγ dr ij, (Yi D Yj D ), Γ dl ij v Φ 2 2mQ 2 15 Langacker, ; Altmannshofer, Gori, Pospelov, Yavin, (Y Q i Y Q j ). Julian Heeck (ULB) Recent flavor anomalies 30 / 27

37 Vector-like quarks II Focus on Γ dl 23 : µµ: b s Γ dl 23 Z C µµ 9 Γ dl 23 g 2 /m 2 Z. B s mixing: b s Z Γ dl 23 Γ dl 23 M 12 /M SM 12 (Γ dl 23 )2 g 2 /m 2 Z. Flavor anomalies µ µ b s m Z' g' TeV Vector-like quarks for Lµ Lτ at LHC B s mixing m Q 15 m Z' g' m Q m Z' g' C 9 1Σ C 9 2Σ sin Θ R 0.05 C 9 2Σ sin Θ R 0.02 Τ 3Μ for sin Θ R neutrino trident production dl 23 J.H., Crivellin, D Ambrosio, PRL 2015, Julian Heeck (ULB) Recent flavor anomalies 31 / 27

38 Vector-like quarks + Vector-like quarks for Lµ Lτ at LHC Put in the second scalar doublet for correlation with τ 3µ: BR() sin 2 θ R cos 2 (α β) tan 2 β. µ h τ BR(τ 3µ) sin 2 θ R g 4 /m 4 Z : µ µ Z µ τ sin Θ R neutrino trident production 1Σ h ΜΤ for tan Β 25 tan Β 50 tan Β 85 cos Α Β 0.2 Τ 3Μ Bs mixing & C9 1Σ future Τ 3Μ m Z' g' TeV At 1σ predict: BR(τ 3µ) (10/ tan β) 2. Julian Heeck (ULB) Recent flavor anomalies 32 / 27

39 L µ L τ at LHC Flavor anomalies Vector-like quarks for Lµ Lτ at LHC Even without Z couplings to quarks: e, p, p µ +, τ + µ +, τ + pp µµz 4µ. Z, γ Ma, Roy, Roy, PLB e +, p, p µ, τ Z µ, τ Currently weaker than limits from neutrino trident production ν µ N ν µ Nµ + µ ( thin dotted line). Altmannshofer, Gori, Pospelov, Yavin, PRL del Aguila, Chala, Santiago, Yamamoto, JHEP 2015 [ ]. Julian Heeck (ULB) Recent flavor anomalies 33 / 27