The quest for New Physics at the Intensity Frontier

Transcription

1 The quest for New Physics at the Intensity Frontier Paride Paradisi University of Padova MASS May 2018, CP 3 Origins, Odense Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

2 Plan of the talk 1 Current status of the (very!) Standard Model 2 Strategies to look for New Physics at low-energy 3 Current anomalies and their interpretations The g 2 of the muon LFUV in semileptonic B decays 4 Conclusions and future prospects Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

3 The SM legacy M W [GeV] % and 95% CL contours 2 f sin (θ ) LEP+SLC eff 2 f direct M and sin (θ ) measurements W eff 2 f fit w/o M, sin (θ ) and Z widths measurements W eff 2 f fit w/o M, sin (θ ) and M measurements W eff H 2 f fit w/o M, sin (θ ), M and Z widths measurements W eff H ± 1σ η ε K summer16 β V ub V cb γ m d m s md M W world comb. ± 1σ -0.5 BR(B τν) α G fitter SM Jul sin 2 (θ l ) eff The LEP legacy Z-pole the 0.1% level Important constraints on many BSM ρ The B-factories legacy Confirmation of the CKM mechanism Important constraints on many BSM Belle II + LHCb phase 2 upgrade: improvement in reach of factor Like going from 8 TeV to TeV! [Tim Gershon s summary Moriond 2017] Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

4 The SM legacy The LHC legacy Higgs Boson mass (combined LHC Run 1 results of ATLAS and CMS) m H Higgs Boson couplings: µ f i = = ± 0.21(stat.) ± 0.11(syst.) σ i Br f (σ i ) SM (Br f ) SM (µ f i signal strengths) γ γ µ ATLAS and CMS LHC Run 1 ATLAS+CMS ATLAS CMS ±1σ ±2σ VBF+VH µ f ATLAS and CMS 3 LHC Run 1 2 H γγ H ZZ H WW H ττ H bb µ ZZ 1 µ WW µ ττ 0 µ bb Parameter value 1 68% CL Best fit SM expected µ f 3 ggf+tth Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

5 The NP scale Gravity = Λ Planck GeV Neutrino masses = Λ see saw GeV BAU: evidence of CPV beyond SM Electroweak Baryogenesis = Λ NP TeV Leptogenesis = Λ see saw GeV Hierarchy problem: = Λ NP TeV Dark Matter (WIMP) = Λ NP TeV SM = effective theory at the EW scale L eff = L SM + d 5 L d=5 yν eff = ij Λ see saw L i L j φφ, L d=6 eff c (d) ij O (d) Λ d 4 ij NP generates FCNC operators Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

6 Hierarchy see-saw Hierarchy see-saw pplhcb2013, Genova] Hierarchy problem: Λ NP TeV SM Yukawas: M W Λ NP M P Flavor problem: Λ NP TeV Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

7 (Desperately) Looking for NP Moriond 2017] We do not have a cross in the map to know where the BSM treasure is, as we had for the Higgs boson: we have to explore the whole territory! Is the BSM treasure is in the territory to be explored? Does it exist at all? The content of the BSM treasure is also a mystery: SUSY, new strong interactions, extra dimensions, something unexpected,...? Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

8 High-intensity frontier Where to look for New Physics at low-energy? Processes very suppressed or even forbidden in the SM LFV processes (µ eγ, µ e in N, τ µγ, τ 3µ, ) CPV effects in the electron/neutron EDMs FCNC & CPV in B s,d & D decay/mixing amplitudes Processes predicted with high precision in the SM EWPO as (g 2) µ: a µ = a exp µ a SM µ (3 ± 1) 10 9 (3σ discrepancy!) LFUV in M lν (with M = π, K, B), B D ( ) lν, B K ll, τ and Z decays Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

9 Experimental status Process Present Experiment Future Experiment µ eγ MEG MEG II µ 3e SINDRUM Mu3e µ Au e Au SINDRUM II? µ Ti e Ti SINDRUM II? µ Al e Al COMET, MU2e τ eγ Belle & BaBar 10 9 Belle II τ µγ Belle & BaBar 10 9 Belle II τ 3e Belle & BaBar Belle II τ 3µ Belle & BaBar Belle II d e(e cm) ACNE? d µ(e cm) Muon (g-2)? Table: Present and future experimental sensitivities for relevant low-energy observables. So far, only upper bounds. Still excellent prospects for exp. improvements. We can expect a NP signal in all above observables below the current bounds. Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

10 On the muon g 2 The muon g-2: experimental status μ July 02 Jan 04? Today: aμ EXP = ( ± 54 stat ± 33 sys )x10-11 [0.5ppm]. Future: new muon g-2 experiments at: Fermilab E989: aims at ± 16x10-11, ie 0.14ppm. Beam expected next year. First result expected in 2018 with a precision comparable to that of BNL E821. J-PARC proposal: aims at phase 1 start with 0.37ppm (2016 revised TDR). Are theorists ready for this (amazing) precision? Not yet [courtesy of M. Passera] M. Passera Parma Jan Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

11 On the muon g 2 The muon g-2: SM vs. Experiment μ Comparisons of the SM predictions with the measured g-2 value: aμ EXP = (63) x E821 Final Report: PRD73 (2006) 072 with latest value of λ=μμ/μp from CODATA 10 a SM µ a µ = a EXP µ a SM µ (57) 330 (85) [1] (51) 273 (81) [2] (58) 250 (86) [3] with the recent conservative hadronic light-by-light a μ HNLO (lbl) = 102 (39) x of F. Jegerlehner arxiv: , and the hadronic leading-order of: [1] Jegerlehner, arxiv: [2] Davier, arxiv:1612: [3] Hagiwara et al, JPG38 (2011) [courtesy of M. Passera] M. Passera Parma Jan Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

12 On leptonic dipoles: l l γ NP effects are encoded in the effective Lagrangian L = e m l 2 ( lr σ µνa ll l L + l Lσ µνa ll l R) F µν l, l = e, µ, τ, Branching ratios of l l γ BR(l l γ) BR(l l ν l ν l ) = 48π3 α ( GF 2 A ll 2 + A l l 2). a l and leptonic EDMs a l = 2m 2 l Re(A ll), d l e = m l Im(A ll ). Naive scaling : a l / a l = m 2 l /m2 l, d l/d l = m l /m l. Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

13 Model-independent predictions BR(l i l j γ) vs. (g 2) µ ( ) 2 ( BR(µ eγ) aµ θeµ ( ) 2 ( BR(τ µγ) aµ θlτ ) 2 ) 2 EDMs assuming Naive scaling d li /d lj = m li /m lj ( ( ) aµ d e )10 28 φ CPV e e cm, ( ) aµ d µ φ CPV µ e cm. Main message: the explanation of the anomaly a µ (3 ± 1) 10 9 requires a NP scenario nearly flavor and CP conserving [Giudice, P.P., & Passera, 12] Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

14 Testing new physics with the electron g 2 Longstanding muon g 2 anomaly a µ = a EXP µ a SM µ (3 ± 1) 10 9 a µ a EW µ = m2 µ (4πv) 2 ( s2 W s4 W ) How could we check if the a µ discrepancy is due to NP? Testing NP effects in a e [Giudice, P.P, & Passera, 12]: a e/ a µ = me/m 2 µ 2 ( ) aµ a e = a e has never played a role in testing NP effects. From ae SM (α) = ae EXP, we extract α which is is the most precise value of α available today! The situation has now changed thanks to th. and exp. progresses. Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

15 The Standard Model prediction of the electron g 2 Using the second best determination of α from atomic physics α( 87 Rb) a e = a EXP e a SM e = 9.2 (8.1) 10 13, Beautiful test of QED at four-loop level! δ a e = is dominated by δa SM e through δα( 87 Rb). Future improvements in the determination of a e (0.2) QED4, (0.2) QED5, (0.2) HAD, (7.6) δα, (2.8) δa EXP. e }{{} (0.4) TH The errors from QED4 and QED5 will be reduced soon to [Kinoshita] Experimental uncertainties from δae EXP and δα dominate! We expect a reduction of δae EXP to a part in (or better). [Gabrielse] Work is also in progress for a significant reduction of δα. [Nez] a e at the (or below) is not too far! This will bring a e to play a pivotal role in probing new physics in the leptonic sector. [Giudice, P.P, & Passera, 12] Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

16 Not only µ eγ... LFV dim-6 L eff = L SM + 1 O dim Λ 2 LFV O dim 6 µ R σ µν H e L F µν, ( µ L γ µ e L ) ( fl γ µ f L ), ( µr e L ) ( fr f L ), f = e, u, d l l γ probe ONLY the dipole-operator (at tree level) l i l j l k l k and µ e in Nuclei probe dipole and 4-fermion operators When the dipole-operator is dominant: BR(l i l j l k lk ) α BR(l i l j γ) CR(µ e in N) α BR(µ eγ) BR(µ 3e) BR(µ eγ) CR(µ e in N) Ratios like Br(µ eγ)/br(τ µγ) probe the NP flavor structure Ratios like Br(µ eγ)/br(µ eee) probe the NP operator at work Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

17 Hints of LFUV in semileptonic B decays LFUV in CC b c transitions (tree-level in the 3.9σ R τ/l D R τ/l D = B(B Dτ ν)exp/b(b Dτ ν)sm B( B Dl ν) exp/b(b Dl ν) SM = 1.34 ± 0.17 = B(B D τ ν) exp/b(b D ( ) τ ν) SM B(B D l ν) exp/b(b D l ν) SM 1.23 ± 0.07 [HFAG averages of BaBar 13, Belle 15, LHCb 15, Fajfer, Kamenik and Nisandzic 12] LFUV in NC b s transitions (1-loop in the 2.6σ R µ/e K R µ/e K B(B K µ µ)exp = B(B Keē) exp = ± [LHCb 14] q 2 [1,6]GeV 2 = B(B K µ µ) exp B(B K eē) exp = ± [LHCb 17] q 2 [1.1,6]GeV 2 while (R µ/e K ) SM = 1 up to few % corrections [Hiller et al, 07, Bordone, Isidori and Pattori, 16]. Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

18 Hints of LFUV in semileptonic B decays [Altmannshofer, Stangl, & Straub, 17] Coeff. best fit 1σ pull C µ [ 2.87, 0.71] 4.1σ C µ [+0.58, +2.00] 4.2σ C9 e [+0.76, +2.48] 4.3σ C10 e 1.27 [ 2.08, 0.61] 4.3σ C µ 9 = Cµ [ 0.98, 0.32] 4.2σ C9 e = C10 e [+0.36, +1.27] 4.3σ C9 e =C10 e 1.91 [ 2.71, 1.10] 3.9σ C µ [ 0.57, +0.46] 0.2σ C µ [ 0.44, +0.51] 0.1σ C 9 e [ 0.49, +0.69] 0.2σ C 10 e 0.04 [ 0.57, +0.45] 0.2σ O l 9 = ( sγ µp L b)( lγ µ l) O l 9 = ( sγ µp R b)( lγ µ l) O l 10 = ( sγ µp L b)( lγ µ γ 5l) O l 10 = ( sγ µp R b)( lγ µ γ 5l) Re C µ 10 Re C e flavio v LFU observables b sµµ global fit all all, fivefold non-ff hadr. uncert Re C µ 9 flavio v LFU observables b sµµ global fit Re C µ 9 Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32 all

19 High-energy effective Lagrangian A simultaneous explanation of both R µ/e K and R τ/l D anomalies naturally selects a left-handed operator ( c L γ µb L )( τ L γ µν L ) which is related to ( s L γ µb L )( µ L γ µµ L ) by the SU(2) L gauge symmetry [Bhattacharya et al., 14]. Global fits of B K ll data favour (not exclusively) an effective 4-fermion operator involving left-handed currents ( s L γ µb L )( µ L γ µµ L ), i.e. the C 9 = C 10 solution [Hiller et al., 14, Hurth et al., 14, Altmannshofer and Straub 14, Descotes-Genon et al., 15, ]. This picture can work only if NP couples much more strongly to the third generation than to the first two. Two interesting scenarios are: Lepton Flavour Violating case: NP couples in the interaction basis only to third generations. Couplings to lighter generations are generated by the misalignment between the mass and the interaction bases [Glashow, Guadagnoli and Lane, 14]. Lepton Flavour Conserving case: NP couples dominantly to third generations but LFV does not arise if the groups U(1) e U(1) µ U(1) τ are unbroken [Alonso et al., 15]. Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

20 LFV case: high-energy effective Lagrangian In the energy window between the EW scale v and the NP scale Λ, NP effects are described by L=L SM + L NP with L invariant under SU(2) L U(1) Y. L NP = C 1 Λ 2 ( q 3Lγ µ q 3L ) ( l3l γ µl 3L ) + C 3 Λ 2 ( q3l γ µ τ a q 3L ) ( l3l γ µτ a l 3L ). After EWSB we move to the mass basis through the unitary transformations u L V uu L d L V d d L ν L U eν L e L U ee L, L NP = 1 Λ [(C 1+C 2 3 ) λ d ij λ e kl ( d Li γ µ d Lj )(ē Lk γ µe Ll ) + B K ( ) ll (C 1 C 3 ) λ d ij λ e kl ( d Li γ µ d Lj )( ν Lk γ µν Ll )] + B K ( ) νν 2C 3 (V λ d ) ij λ e kl (ū Li γ µ d Lj )(ē Lk γ µν Ll )+h.c.] B D ( ) lν [Calibbi, Crivellin, Ota, 15] λ d ij = V d3iv d3j λ e ij = U e3iu e3j V u V d = V CKM V Assumption for the flavor structure: λ d,e 33 1, λd,e 22 = λd,e 23 2, λ d,e 13 = 0. Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

21 Semileptonic observables B K l l R µ/e K (C 1 + C 3 ) Λ 2 (TeV) λ d 23 λ e (R µ/e K ) exp < 1 R τ/l D ( ) B K ν ν R τ/l C ( ) λd 23 λ e D ( ) Λ 2 33 (TeV) V cb (R τ/l D ( ) ) exp > 1 RK νν (C ( ) 1 C 3 ) λ d (C ( ) 1 C 3 ) 2 λ d 2 23 Λ 2 (TeV) 0.01 Λ 4 (TeV) 0.01 RK νν B(B K ν ν) = 4.3 B(B K ν ν) SM The correct pattern of deviation from the SM is reproduced for C 3 < 0, λ d 23 < 0 and λ d 23 /V cb 1. For C 3 O(1), we need Λ 1 TeV and λ e [Calibbi, Crivellin and Ota, 15] Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

22 Low-energy effective Lagrangian Construction of the low-energy effective Lagrangian: running and matching We use the renormalization group equations (RGEs) to evolve the effective lagrangian L NP from µ Λ down to µ 1 GeV. This is done is three steps: First step: the RGEs in the unbroken SU(2) L U(1) Y theory [Manohar et al., 13] are used to compute the coefficients in the effective lagrangian down to a scale µ m Z. Second step: the coefficients are matched to those of an effective lagrangian for the theory in the broken symmetry phase of SU(2) L U(1) Y, that is U(1) el. Third step: the coefficients of this effective lagrangian are computed at µ 1 GeV using the RGEs for the theory with the only U(1) el gauge group. Then we take matrix elements of the relevant operators. The scale dependence of the RGE contributions cancels with that of the matrix elements. [Feruglio, P.P., Pattori, PRL 16, 17] Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

23 Leptonic Z-coupling modifications L NP induces modification of the W, Z couplings L NP = 1 Λ [(C 1+C 2 3 ) λ u ij λ e kl (ū Li γ µ u Lj )( ν Lk γ µν Ll ) + (C 1 C 3 ) λ u ij λ e (u kl Li γ µ u Lj )(ē Lk γ µe Ll ) +... ] L Z = g ( ) 2 ē i Z/ g ij ll c P L + Z/ g ij lr P R e j + g 2 ν Li Z/ g ij νl W c ν Lj W g ij ll v 2 ( ) ( ) 3y 2 Λ 2 t (C 1 C 3 )λ u 33 + g2c 2 Λ λ e ij 3 log m Z 16π 2 g ij νl v 2 ( ) ( ) 3y 2 Λ 2 t (C 1 +C 3 )λ u 33 g2c 2 Λ λ e ij 3 log 16π 2 m Z Figure: Z couplings with fermions. Upper: RGE induced coupling. Lower: one-loop diagram. Approximate LO results obtained adding to the RGE contributions from gauge and top yukawa interactions the one-loop matrix element. The scale dependence of the RGE contribution cancels with that of the matrix element dominated by a quark loop. Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

24 Z-pole observables Non-universal leptonic vector and axial-vector Z couplings [PDG] v τ [(C 1 C 3 )λ u C 3 ] v e Λ 2 (TeV) a τ [(C 1 C 3 )λ u C 3 ], a e Λ 2 (TeV) to be compared with the LEP result [PDG] v τ v e = ± 0.029, a τ a e = ± Number of neutrinos N ν from the invisible Z decay width N ν [(C 1 + C 3 )λ u C 3 ] Λ 2 (TeV) to be compared with the LEP result [PDG] N ν = ± Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

25 Purely leptonic effective Lagrangian Quantum effects generate a purely leptonic effective Lagrangian: L NC eff L CC eff = 4G [ F λ e ij (e Li γ µe Lj ) 2 ψ ψγµ ψ ( ] 2gψc Z e t Q ψ c e ) γ + h.c. = 4G [ ] F λ e ij c cc t (e Li γ µν Lj )(ν Lk γ µ e Lk + u Lk γ µ V kl d Ll ) + h.c. 2 ψ = {ν Lk, e Lk,Rk, u L,R, d L,R, s L,R } g Z ψ = T 3 (ψ) Q ψ sin 2 θ W c e t = y 2 t c cc t c e γ = 3 v 2 32π 2 Λ (C 1 C 2 3 )λ u 33 log Λ2 mt 2 = y 2 3 v 2 t 16π 2 Λ C 2 3 λ u 33 log Λ2 mt 2 ] e2 v [(3C 2 48π 2 Λ 2 3 C 1 ) log Λ2 µ Figure: Diagram generating a four-lepton process. Top-quark yukawa interactions affect both neutral and charged currents. Gauge interactions are proportional to e 2 and to the e.m. current. Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

26 LFU violation in τ l νν LFU breaking effects in τ l νν R τ/e τ R τ/µ τ Rτ τ/l : experiments vs. theory R τ/µ τ B(τ µν ν)exp/b(τ µν ν)sm = B(µ eν ν) exp/b(µ eν ν) SM B(τ eν ν)exp/b(τ eν ν)sm = B(µ eν ν) exp/b(µ eν ν) SM = ± , R τ/e τ = ± [HFAG, 14] R τ/l D ( ) : experiments vs. theory R τ/l R τ/l τ C 3 Λ 2 (TeV) λu 33λ e 33 D = 1.37 ± 0.17, R τ/l D = 1.28 ± 0.08 R τ/l C ( ) λd 23 λ e D ( ) Λ 2 33 (TeV) V cb Strong tension between R τ/l τ and R τ/l D Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

27 LFV decays LFV τ decays (1-loop) B(τ 3µ) (C 1 C 3 ) 2 Λ 4 (TeV) B(τ 3µ) B(τ µρ) B(τ µπ) ( ) λ e LFV B decays (tree-level) B(B K τµ) C µτ C µµ , since C µµ 9 /C µτ 9 λ e 23 and C µµ from R e/µ K Experimental bounds [HFAG]: B(τ 3µ) exp B(τ µρ) exp B(τ µπ) exp B(B K τµ) exp λ e 23 Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

28 B anomalies [Feruglio, P.P., Pattori, PRL 16, 17] Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

29 Discussion Question: are there ways out to the EWPT bounds discussed here? Log effects can be cancelled/suppressed by finite terms, not captured by our RGE-based approach, which require the knowledge of the complete UV theory. Our starting point can be generalized by allowing more operators at the scale Λ, making it possible cancellation/suppression of log effects [Barbieri et al, 16, Isidori et al, 17] EWPT constraints are relaxed if λ d 23 V cb [Crivellin, Muller and Ota, 17] λ d 23 1, λe , Λ 5 TeV = R τ/l D ( ) λ d 23 1, λe 22 1, Λ 30 TeV = Rµ/e K ( ) λ d 23 1, λe , Λ 5 TeV = R τ/l and Rµ/e D ( ) K ( ) λ d 23 1 requires a large fine tuning to reproduce the CKM matrix V CKM = V u V d λ q ij = V q3i V q3j (q = u, d) Answer: Yes but they require some amount of fine tunings. Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

30 U(2) EFT-type n flavor considerations symmetry [Isidori [U(2) et al., n Barbieri flavor et al., symmetry] 16, 17] This coherent picture leads to several testable predictions Testable predictions in models with U(2) n in other low-energy flavor symmetry observables: b c(u) lν BR(B D * τν)/br SM = BR(B Dτν)/BR SM = BR(Λ b Λ c τν)/br SM = BR(B π τν)/br SM = BR(Λ b p τν)/br SM = BR(B u τν)/br SM b s μμ b s ττ b s νν K π νν ( to be checked in several other modes...) NP ~ SM large enhancement (easily 10 SM) ~ O(1) deviation from SM in the rate ~ O(1) deviation from SM in the rate Meson mixing τ decays ~ 10% deviations from SM both in ΔM Bs & ΔM Bd τ 3μ not far from present exp. Bound (BR ~ 10-9 ) Planck 2017] Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

31 Collider bounds & B anomalies The b cτν process is related to b b τ + τ L eff U g U 2 [ (Vcb ( c MU 2 L γ µ b L )( τ L γ µν L ) + h.c.) + ( b L γ µ b L )( τ L γ µτ L ) ] The explanation of the b cτν anomaly is constrained by LHC searches gu Vector LQ exclusion ATLAS ττ: 13 TeV, 3.2 fb -1 ATLAS ττ: 8 TeV, 19.5 fb -1 13TeV, 300 fb -1 RD@1σ b b τ + LHC b τ b τ + b τ M U (TeV) [Faroughy, Greljo, Kamenik, 16] b τ + Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32

32 Conclusions and future prospects Important questions in view of ongoing/future experiments are: What are the expected deviations from the SM predictions induced by TeV NP? Which observables are not limited by theoretical uncertainties? In which case we can expect a substantial improvement on the experimental side? What will the measurements teach us if deviations from the SM are [not] seen? (Personal) answers: We can expect any deviation from the SM expectations below the current bounds. LFV processes, leptonic EDMs and LFUV observables do not suffer from theoretical limitations and there are still excellent prospects for experimental improvements. The observed LFUV in B D ( ) lν, B K ll might be true NP signals. It s worth to look for LFUV in B (c) lν, B K ττ, Λ b Λ cτν and τ lνν,... If LFUV arise from LFV sources, the most sensitive LFV channels are typically not B-decays but τ decays such as τ µll and τ µρ,... The longstanding (g 2) µ anomaly will be checked soon by the experiments E989 at Fermilab and E34 at J-PARK. If confirmed it will imply NP at/below the TeV scale! Message: an exciting Physics program is in progress at the Intensity Frontier! Paride Paradisi (University of Padova) The quest for New Physics at the Intensity Frontier MASS / 32