Implications of lepton universality violation in B-meson decays J. Martin Camalich JLab Webinar May 24th 2021 Why studying (quark) Flavor Physics in the 2020’s? 1 - Big Questions CKM and mass matrices: Parametrizations of flavor phenomena in the SM The SM Flavor Puzzle I Some quark masses seem “tuned” Anthropic arguments! I Origin of CP-violation, baryogenesis, strong CP I Why does Nature need three generations at all? However, the solution might not be accessible at the energies at reach. J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 2 / 28 2 - Precision physics programme Quark mixing in precision regime since decades ago! 15 I High-Luminosity LHC: Expected 10 bb¯ pairs !! HL-LHC Yellow Book A. Cerri et al., arXiv: 1812.07638 ca. 200 pages PDG I 3 mixing angles and 1 CPV phase I 6 quark masses CKM: Cabibbo-Kobayashi-Maskawa paradigm 0 1 1−λ2=2 λ Aλ3(ρ−iη) B 2 2 C VCKM ' @ −λ 1−λ =2 Aλ A Aλ3(1−ρ−iη) −Aλ2 1 λ = 0:2253(7), A = 0:808(22), ρ¯ = 0:132(22), η¯ = 0:341(13) Jure Zupan, arXiv: 1903.05062 J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 3 / 28 2 - Precision physics programme Quark mixing in precision regime since decades ago! 15 I High-Luminosity LHC: Expected 10 bb¯ pairs !! HL-LHC Yellow Book A. Cerri et al., arXiv: 1812.07638 ca. 200 pages PDG I 3 mixing angles and 1 CPV phase I 6 quark masses CKM: Cabibbo-Kobayashi-Maskawa paradigm J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 3 / 28 Very sensitive probes of “generic” new physics Theorem: FCNC are “Loop-Suppressed” in the SM! I Prototypical example: FCNCs Loop Weak z }| { Flavor z}|{ y 2 z }| { M ∼ G t (V ∗V )2 SM F 16π2 ts tb | {z } GIM I Flavour observables probe (indirectly) very high energy scales! M. Neubert at EPS 2011 J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 4 / 28 Effective field theories and bottom-up approach to new physics Legacy of Flavor Physics Program I High precision measurements of SM mixing parameters I Discover New Physics OR set the lower bounds on ΛFlavor J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 5 / 28 Flavor physics was instrumental in discovering and shaping the SM I Nuclear β-decays: Discovery weak interactions and neutrino I Rare Kaon-decays: Discovery of the charm quark I Kaon decays: Discovery of CP violation =) Discovery of 3 generations Expect the unexpected Thanks to Zoltan Ligeti for sharing this J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 6 / 28 3 - Flavor anomalies! Gauge interactions are generation independent! Hints for Lepton Flavor Universality Violation (LFUV)? “The flavour of new physics”, JMC & J. Zupan, CERN courier, May/June 2019 J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 7 / 28 Flavor Anomalies: b s`+`− ! Leptons do not feel the strong force! B(B¯!K (∗)µ+µ−) SM R (∗) = ' 1 K B(B¯!K (∗)e+e−) Deficits on RK (∗) measured by LHCb Signal of µ-to-e LFUV at 2-4σ J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 8 / 28 Flavor Anomalies: b s`+`− ! Leptons do not feel the strong force! B(B¯!K (∗)µ+µ−) SM R (∗) = ' 1 K B(B¯!K (∗)e+e−) Deficits on RK (∗) measured by LHCb Other anomalies in branching ratios and angular observables Claims of > 5σ signal of NP in global fit to ca. 100+ observables J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 8 / 28 Our previous analyses of b s`` ! 1 Anatomy and model-independent parametrization of hadronic uncertainties Beneke et al. NPB592(2001)3, Jäeger and JMC JHEP1305(2013)043, PRDD93(2016)1,014028 0 I Were at the center of “P5 controversies” (hadronic effects vs. NP) Bharucha et al.JHEP 1009 (2010) 090, Descotes-Genon et al. JHEP 1412 (2014) 125, Lyon et al. arXiv:1406.0566, Ciuchini et al. arXiv:1512.07157 + many, many more papers. 2 First theoretical analysis of the first RK measurement 3 Among first combined theoretical analyses of RK (∗) Emphasize lepton-universality ratios and Bs ! µµ to discover NP J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 9 / 28 Announcement of new LHCb results on RK and Bs ! µµ! Quick (last-second) reaction to analyse the new results J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 10 / 28 Announcement of new LHCb results on RK and Bs ! µµ! Collaboration between: I Beihang University: Li-Sheng Geng, Shuang-Yi Li and Rui-xiang Shi I UC San Diego: Benjamín Grinstein I U. Sussex: Sebastian Jäger I Instituto de Astrofísica de Canarias: JMC Other related work appeared around the same time: Hiller et al. 2103.12724 [hep-ph], Angelescu et al. 2103.12504 [hep-ph], Altmannshofer et al. 2103.13370 [hep-ph], Cornella et al. 2103.16558 [hep-ph], Greljo et al. 2103.13991 [hep-ph], . J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 10 / 28 Effective field theory approach to b s`` decays ! CC (Fermi theory): bLLW s ∗ µ ) GF Vcb Vcs C2 c¯Lγ bL s¯LγµcL c c FCNC: b s bRLW s RL t W e t t ) ∗ ¯ σ µν 2 GF Vtb Vts mb C7 sL µν bR F γ γ 4π b s b s b s LLW LLt LLt W t t W ∗ α µ ¯ Z, γ Z, γ ) GF Vtb Vts C9(10) s¯Lγ bL `γµ(γ5)` ν 4π l l l l l l 0 ¯ I New-Physics also in Ci or e.g. Oi obtained PL ! PR in sLb l l I Light fields active at long distances b s Nonperturbative QCD! B K∗ F Factorization of scales mb vs. ΛQCD HQEFT, QCDF, SCET,.. d J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 11 / 28 A beautiful example: B0 `` q ! Marco Santimaria @ CERN, March 23rd 2021 b Z l Bq l q 2 2 ∗ 2 2 2 0 2 Bs` / GF α jVtbVts j m` fBs jC10 − C10j Semileptonic decay constants fBq can be calculated in LQCD FLAG averages SM −9 Include radiative corrections: Bsµ = 3:66(14) × 10 Beneke et al. JHEP10(2019)232 ∼ 2 − 3σ deficit with respect to SM predictions! J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 12 / 28 A beautiful example: B0 `` q ! Marco Santimaria @ CERN, March 23rd 2021 2 2 ∗ 2 2 2 0 2 Bs` / GF α jVtbVts j m` fBs jC10 − C10j Semileptonic decay constants fBq can be calculated in LQCD FLAG averages SM −9 Include radiative corrections: Bsµ = 3:66(14) × 10 Beneke et al. JHEP10(2019)232 ∼ 2 − 3σ deficit with respect to SM predictions! J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 12 / 28 A rich (and complex) example: B K ∗( K π)`` ! ! d(4)Γ 9 s 2 c 2 2 = 32π (I1 sin θk +I1 cos θk dq d(cos θl )d(cos θk )dφ s 2 c 2 2 2 + (I2 sin θk +I2 cos θk ) cos 2θl +I3 sin θk sin θl cos 2φ 2 + I4 sin 2θk sin 2θl cos φ+I5 sin 2θk sin θl cos φ+I6 sin θk cos θl 2 2 + I7 sin 2θk sin θl sin φ+I8 sin 2θk sin 2θl sin φ+I9 sin θk sin θl sin 2φ) Anomalies in the angular observables . I Blurred by hadronic uncertainties 0 I5 ATLAS, JHEP 10 (2018) 047 P5 = p 2 −I2sI2c I Cancel leading theory uncertainties New physics? µ δC9 ' −1 Descotes-Genon et al. PRD88,074002 Most precise measurement: LHCb, PRL125(2020)011802 J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 13 / 28 Large-recoil region (low q2) I No LQCD (Sum Rules, models ...) and QCDf and SCET (power-corrections) I Dominant effect of the photon pole Charmonium region I Dominated by long-distance (hadronic) effects 2 2 I Starting at the perturbative cc¯ threshold q ' 6 − 7 GeV Low-recoil region (high q2) I LQCD+HQEFT + OPE (duality violation) I Dominated by semileptonic operators J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 14 / 28 Anatomy of the amplitude in a nutshell Jäger and JMC, PRD93 (2016) no.1, 014028 Helicity amplitudes λ = ±1; 0 eff C9 z }| { n m2 m^ m o H (λ) = −iN C V~ + B h − b B C T~ ; V 9 Lλ q2 λ q2 7 Lλ ~ HA(λ) = −iNC10VLλ Hadronic form factors: 7 independent q2-dependent nonperturbative functions “Charm” contribution Z 4 iq·y ¯ ∗ em;had,µ ¯ hλ / d ye hK jT fj (y); O1;2(0)gjBi Charm and O9 are tied up by renormalization eff Only C9 is observable! J. Martin Camalich (IAC&ULL) Implications of LUV in B-meson decays May 24th 2021 15 / 28 The lepton-universality ratios Leptons do not feel the strong force! B(B¯!K (∗)µ+µ−) SM R (∗) = ' 1 K B(B¯!K (∗)e+e−) Very clean null tests of the SM Sensitive to muonic LH currents! I Th. uncertainties negligible! Geng, Grinstein, Jäger, JMC, Ren, Shi, PRD96(2017)093006 J.