DOCSLIB.ORG

Rare Charm Decays at Lhcb

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Rare Charm Decays at Lhcb Rare charm decays at LHCb Chris Burr on behalf of the LHCb collaboration 28th July 2020 - ICHEP 2020 Image: CERN-EX-66954B © 1998-2018 CERN The search for + ± + ′∓! D(s) → h ℓ ℓ LHCb-PAPER-2020-007 (in preparation) ➤ Search for 25(!) decays of the form + ± + ′∓! D(s) → h ℓ ℓ ➤ h is a charged kaon or pion ➤ ℓ is an electron or muon ➤ Includes LFV and LNV decays ➤ Topologically similar but underlying processes vary + + + − + + + − + + + − + + + − + + + − D → π μ μ D → π e e D → K e e Ds → π e μ Ds → K μ e + − + + + − + + + + + − + + + − + − + + D → π μ μ D → π e e Ds → π μ μ Ds → π e e Ds → K μ e + + + − + + + − + − + + + − + + + + + − D → π μ e D → K μ μ Ds → π μ μ Ds → π e e Ds → K e μ + − + + + + + − + + + − + + + − + + + − D → π μ e D → K μ e Ds → π μ e Ds → K μ μ Ds → K e e + + + − + + + − + − + + + − + + + − + + D → π e μ D → K e μ Ds → π μ e Ds → K μ μ Ds → K e e Allowed in the standard model Effectively forbidden in the standard model [email protected] ○ ICHEP 2020 ○ Rare charm decays at LHCb 2 Why study rare charm decays? ➤ Standard Model allowed decays involve FCNC or Weak Annihilation ➤ Forbidden at tree level in the Standard Model and CKM suppressed ➤ Additionally suppressed in charm by the GIM mechanism ➤ Expected to be dominated by long distance tree-level contributions ➤ Scope for a wide range of null tests of the Standard Model† Standard Model prediction for D+ → π+μ+μ− Stefan de Boer and Gudrun Hiller ○ Phys. Rev. D 93, 074001 † Eur. Phys. J. C80(2020) 65 [email protected] ○ ICHEP 2020 ○ Rare charm decays at LHCb 3 Why study rare charm decays? ➤ Potential for enhancements from BSM physics (leptoquarks, MSSM, …) ➤ Complimentary to other measurements Mediated by a Majorana neutrino Mediated by a oscillating Standard Model neutrino (far beyond the reach of any planned experiment) [email protected] ○ ICHEP 2020 ○ Rare charm decays at LHCb 4 Anomalies ➤ Several results involving b → sℓ+ℓ− are in tension with the Standard Model ➤ Angular distributions in B0 → (K*0 → K+π−) μ+μ− decays ' 5 P 1 LHCb Run 1 + 2016 SM from DHMV 0.5 LHCb-PAPER-2020-002 0 See: Lepton Flavour Violation at LHCb #462 −0.5 (1S) ψ (2S) / J ψ −1 0 5 10 15 q2 [GeV2/c4] ➤ Lower than expected branching fractions at low m (ℓ+ℓ−) for many decays involving b → sμ+μ− LCSR Lattice Data ] 4 ] 9 c 2 -2 LHCb 5 B+→ K+µ+µ− 8 7 SM pred. GeV /GeV 4 LHCb -8 4 6 Data c [10 × 5 3 2 q -8 4 2 )/d µ 3 [10 µ 2 φ 2 q 1 → /d 0 s 1 B B d 0 0 0 5 10 15 20 5 10 15 q2 [GeV2/c4] dB( q2 [GeV2/c4] LHCb-PAPER-2014-006 Phys. Rev. D 93, 074501 LHCb-PAPER-2015-023 [email protected] ○ ICHEP 2020 ○ Rare charm decays at LHCb 5 Why study rare charm decays at LHCb? ➤ LHCb has the world’s largest sample of charm decays ➤ Excellent particle identification and momentum/vertex resolution ➤ Enables extremely precise measurements ➤ Observation of D0 → h+h−ℓ+ℓ− and subsequent angular constraints (LHCb-PAPER-2017-019 and LHCb-PAPER-2018-020) ➤ World’s most precise constraints on D0 → μ+μ− and D0 → μ+e− (LHCb-PAPER-2013-013 and LHCb-PAPER-2015-048) ➤ World’s most precise constraints on + ± + ∓ (LHCb-PAPER-2012-051) D(s) → π μ μ ) 2 60 50 S 1.0 2 c c LHCb Data 45 CL 0.9 Observed CLs 50 LHCb (b) Fit 40 0.8 Expected CLs - Median 40 D0→K +K −µ +µ − 35 0.7 Expected CLs ± 1 σ 0 Expected CLs ± 2 σ D →K +K −π +π − 30 0.6 30 Comb. backg. 25 0.5 20 0.4 + 20 Previous LHCb Ds results 15 0.3 10 0.2 Candidates per 5 MeV/ 10 Candidates / (10 MeV/ 5 0.1 0 0 0.0 -8 1850 1900 1800 1850 1900 1950 2000 0 2 4 6 ◊± 10 + − + − 2 2 0 ± m(K K µ µ ) [MeV/c ] mµ +µ − [MeV/c ] B(D ⇥ e µ ) LHCb-PAPER-2018-020 LHCb-PAPER-2013-013 LHCb-PAPER-2015-048 [email protected] ○ ICHEP 2020 ○ Rare charm decays at LHCb 6 Datasets LHCb-PAPER-2020-007 (in preparation) ➤ Analysis performed on LHCb’s 2016 dataset (1.7 fb−1) ➤ + + − + Normalised to D(s) → (ϕ → ℓ ℓ ) π ➤ Regions dominated by resonances are vetoed when fitting for the signal 5000 + + D LHCb Preliminary D Combined + 500 + + Ds Ds D →⇡⇡⇡ + 4000 Non-peaking Non-peaking Ds →⇡⇡⇡ Combined 400 LHCb Preliminary D+→⇡⇡⇡ 3000 + Ds →⇡⇡⇡ 300 2000 200 Candidates per 2 MeV Candidates per 4 MeV 1000 100 0 0 1850 1900 1950 2000 2050 1850 1900 1950 2000 2050 + + + + m (⇡ µ µ−) [MeV] m (⇡ e e−) [MeV] [email protected] ○ ICHEP 2020 ○ Rare charm decays at LHCb 7 Challenges with electrons ➤ Problem: Electrons loose momentum to bremsstrahlung radiation 8.5. ELECTRON IDENTIFICATION 77 ➤ Solution: Apply corrections based on calorimeter energy deposits ➤ But: Deposit location varies depending on when the photon was emitted 0.05 ECAL Magnet electrons 0.04 hadrons γ E1 0.03 Downstream bremsstrahlung p 0.02 γ e Upstream 0.01 E0 bremsstrahlung E2 0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Figure 8.16: Schematic illustration of E / p ➤ Correctionscluster track are appliedBremsstrahlung but the resolution correction. Anis still electron affected may Figure 8.14: The ratio of uncorrected energy of the radiate photons when passing through material charged [email protected] in ECAL to ○ the ICHEP momentum 2020 ○ Rare charm of decays re- at LHCbbefore or after the magnet: in the first case, a well 8 constructed tracks for electrons (open histogram) defined cluster is seen in the ECAL, with energy and hadrons (shaded histogram). E1,whilstinthesecondcasetheBremsstrahlung energy forms part of the electron cluster with energy E2;forelectronidentificationE2 = p, the momentum measured in the spectrometer, while the energy of the electron at the origin, 0.1 E0 = E1+ E2. (a) (b) 0.03 electrons 0.08 hadrons (ghosts are ignored). After normalisation the his- 0.06 0.02 tograms provide the likelihood distributions for 0.04 electrons and background. For a given track, the 0.01 difference of log-likelihood for the electron and non- 0.02 electron hypotheses are computed, and summed 0 0 0 100 200 300 400 0 100 200 300 400 for the different variables. Finally, the Calorime- 2 χ2 χ e brem ter information is combined with the RICH and Muon detectors, as described Sect. 8.3, significantly (c) (d) 0.03 improving the electron identification performance. -1 10 The log-likelihood difference ∆ln eπ is shown in Fig. 8.17, for tracks that have informationL avail- 0.02 able from the Calorimeter system. -2 10 0.01 To illustrate the performance of electron iden- tification, the J/ψ mass plot is shown as the open 0 points in Fig. 8.13(b). The signal is fit with a func- 0 20 40 60 80 100 120 140 0 2 4 6 8 10 tion including a radiative tail, to account for the E (MeV) E (GeV) PS HCAL imperfect correction of Bremsstrahlung. The back- Figure 8.15: Electron identification estimators: ground is larger than in the muon channel, and 2 (a) the value for the χe estimator for track- is either due to real (secondary) electrons, or due cluster energy/position matching procedure for re- to one of the pair of tracks being a ghost track; constructed tracks and charged clusters in ECAL, the contribution from misidentified hadrons is very 2 (b) the value of the χbrem estimator, (c) the energy small. These background tracks are dominantly of deposited in the Preshower, and (d) the deposi- low pT,andcanbeefficientlyrejectedbyapply- tion of the energy along the extrapolated particle ing the requirement pT > 0.5GeV/c for the elec- trajectory in the hadron calorimeter. The track tron candidates, as shown by the solid points in sample for these plots was taken from a selection Fig. 8.13 (b). of B-decay channels, and the shaded component la- The average efficiency to identify electrons in + belled “hadrons” also includes the muons from that the calorimeter acceptance from J/ψ e e− sample; the electron and hadron distributions are 0 0 → decays in B J/ψ KS events is 95%, for a normalised (including overflows). pion misidentification→ rate of 0.7%, as shown in Signal samples LHCb-PAPER-2020-007 (in preparation) ➤ PID used to suppress hadronic backgrounds ➤ Signal is extracted using a fit to the three body invariant mass ➤ Peaking background modelled using fast simulation generated with RapidSim† ➤ Variation in the sources of background in different final states 300 Non-peaking Non-peaking LHCb Preliminary D+→⇡⇡⇡ D+→⇡⇡⇡ LHCb Preliminary 50 + 250 + Ds →⇡⇡⇡ Ds →⇡⇡⇡ 60 Combined Combined 40 200 40 30 150 20 100 Non-peaking 20 D+→K⇡⇡ + 10 50 Ds →K⇡⇡ Candidates per 4 MeV Candidates per 4 MeV LHCb Preliminary Candidates per 4 MeV Combined 0 0 0 1850 1900 1950 2000 2050 1850 1900 1950 2000 2050 1850 1900 1950 2000 2050 m (⇡⌥µ±µ±) [MeV] m (⇡⌥µ±e±) [MeV] m (K±e±e⌥) [MeV] † Computer Physics Communications 214C (2017) pp. 239-246 [email protected] ○ ICHEP 2020 ○ Rare charm decays at LHCb 9 Results LHCb-PAPER-2020-007 (in preparation) ➤ All results consistent with background only hypothesis + + + D ⇡−µ µ ! + + + D ⇡ µ µ− ! + + + D K µ µ− ! + + + D ⇡−µ e ! + + + D ⇡ e µ− ! + + + D ⇡ µ e− ! + + + D K e µ− ! + + + D K µ e− ! + + + D ⇡−e e ! + + + D ⇡ e e− ! + + + LHCb Preliminary D K e e− ! 8 7 6 5 10− 10− 10− 10− 2016 limit at 90% confidence + + + Ds ⇡−µ µ + ! + + Ds ⇡ µ µ− + ! + + Ds K−µ µ + ! + + Ds K µ µ− +! + + Ds ⇡−µ e + ! + + Ds ⇡ e µ− + ! + + Ds ⇡ µ e− + ! + + Ds K−µ e + ! + + Ds K e µ− + ! + + Ds K µ e− +! + + Ds ⇡−e e + ! + + Ds ⇡ e e− + ! + + D K−e e s ! PRELIMINARY! + + + LHCb Preliminary D K e e− s ! 8 7 6 5 10− 10− 10− 10− 2016 limit at 90% confidence | expected median with ±1σ, ±2σ intervals ○ x observed limit ○ | previous world's best limit (BaBar, CLEO, LHCb) [email protected] ○ ICHEP 2020 ○ Rare charm decays at LHCb 10 Conclusions ➤ 25 rare/forbidden charm decays have been searched for ➤ No significant deviation from
Load more

Recommended publications
  • Particle Physics Dr Victoria Martin, Spring Semester 2012 Lecture 12: Hadron Decays
    Particle Physics Dr Victoria Martin, Spring Semester 2012 Lecture 12: Hadron Decays !Resonances !Heavy Meson and Baryons !Decays and Quantum numbers !CKM matrix 1 Announcements •No lecture on Friday. •Remaining lectures: •Tuesday 13 March •Friday 16 March •Tuesday 20 March •Friday 23 March •Tuesday 27 March •Friday 30 March •Tuesday 3 April •Remaining Tutorials: •Monday 26 March •Monday 2 April 2 From Friday: Mesons and Baryons Summary • Quarks are confined to colourless bound states, collectively known as hadrons: " mesons: quark and anti-quark. Bosons (s=0, 1) with a symmetric colour wavefunction. " baryons: three quarks. Fermions (s=1/2, 3/2) with antisymmetric colour wavefunction. " anti-baryons: three anti-quarks. • Lightest mesons & baryons described by isospin (I, I3), strangeness (S) and hypercharge Y " isospin I=! for u and d quarks; (isospin combined as for spin) " I3=+! (isospin up) for up quarks; I3="! (isospin down) for down quarks " S=+1 for strange quarks (additive quantum number) " hypercharge Y = S + B • Hadrons display SU(3) flavour symmetry between u d and s quarks. Used to predict the allowed meson and baryon states. • As baryons are fermions, the overall wavefunction must be anti-symmetric. The wavefunction is product of colour, flavour, spin and spatial parts: ! = "c "f "S "L an odd number of these must be anti-symmetric. • consequences: no uuu, ddd or sss baryons with total spin J=# (S=#, L=0) • Residual strong force interactions between colourless hadrons propagated by mesons. 3 Resonances • Hadrons which decay due to the strong force have very short lifetime # ~ 10"24 s • Evidence for the existence of these states are resonances in the experimental data Γ2/4 σ = σ • Shape is Breit-Wigner distribution: max (E M)2 + Γ2/4 14 41.
    [Show full text]
  • Arxiv:1502.07763V2 [Hep-Ph] 1 Apr 2015
    Constraints on Dark Photon from Neutrino-Electron Scattering Experiments S. Bilmi¸s,1 I. Turan,1 T.M. Aliev,1 M. Deniz,2, 3 L. Singh,2, 4 and H.T. Wong2 1Department of Physics, Middle East Technical University, Ankara 06531, Turkey. 2Institute of Physics, Academia Sinica, Taipei 11529, Taiwan. 3Department of Physics, Dokuz Eyl¨ulUniversity, Izmir,_ Turkey. 4Department of Physics, Banaras Hindu University, Varanasi, 221005, India. (Dated: April 2, 2015) Abstract A possible manifestation of an additional light gauge boson A0, named as Dark Photon, associated with a group U(1)B−L is studied in neutrino electron scattering experiments. The exclusion plot on the coupling constant gB−L and the dark photon mass MA0 is obtained. It is shown that contributions of interference term between the dark photon and the Standard Model are important. The interference effects are studied and compared with for data sets from TEXONO, GEMMA, BOREXINO, LSND as well as CHARM II experiments. Our results provide more stringent bounds to some regions of parameter space. PACS numbers: 13.15.+g,12.60.+i,14.70.Pw arXiv:1502.07763v2 [hep-ph] 1 Apr 2015 1 CONTENTS I. Introduction 2 II. Hidden Sector as a beyond the Standard Model Scenario 3 III. Neutrino-Electron Scattering 6 A. Standard Model Expressions 6 B. Very Light Vector Boson Contributions 7 IV. Experimental Constraints 9 A. Neutrino-Electron Scattering Experiments 9 B. Roles of Interference 13 C. Results 14 V. Conclusions 17 Acknowledgments 19 References 20 I. INTRODUCTION The recent discovery of the Standard Model (SM) long-sought Higgs at the Large Hadron Collider is the last missing piece of the SM which is strengthened its success even further.
    [Show full text]
  • 11. the Cabibbo-Kobayashi-Maskawa Mixing Matrix
    11. CKM mixing matrix 103 11. THE CABIBBO-KOBAYASHI-MASKAWA MIXING MATRIX Revised 1997 by F.J. Gilman (Carnegie-Mellon University), where ci =cosθi and si =sinθi for i =1,2,3. In the limit K. Kleinknecht and B. Renk (Johannes-Gutenberg Universit¨at θ2 = θ3 = 0, this reduces to the usual Cabibbo mixing with θ1 Mainz). identified (up to a sign) with the Cabibbo angle [2]. Several different forms of the Kobayashi-Maskawa parametrization are found in the In the Standard Model with SU(2) × U(1) as the gauge group of literature. Since all these parametrizations are referred to as “the” electroweak interactions, both the quarks and leptons are assigned to Kobayashi-Maskawa form, some care about which one is being used is be left-handed doublets and right-handed singlets. The quark mass needed when the quadrant in which δ lies is under discussion. eigenstates are not the same as the weak eigenstates, and the matrix relating these bases was defined for six quarks and given an explicit A popular approximation that emphasizes the hierarchy in the size parametrization by Kobayashi and Maskawa [1] in 1973. It generalizes of the angles, s12 s23 s13 , is due to Wolfenstein [4], where one ≡ the four-quark case, where the matrix is parametrized by a single sets λ s12 , the sine of the Cabibbo angle, and then writes the other angle, the Cabibbo angle [2]. elements in terms of powers of λ: × By convention, the mixing is often expressed in terms of a 3 3 1 − λ2/2 λAλ3(ρ−iη) − unitary matrix V operating on the charge e/3 quarks (d, s,andb): V = −λ 1 − λ2/2 Aλ2 .
    [Show full text]
  • Charm Meson Molecules and the X(3872)
    Charm Meson Molecules and the X(3872) DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Masaoki Kusunoki, B.S. ***** The Ohio State University 2005 Dissertation Committee: Approved by Professor Eric Braaten, Adviser Professor Richard J. Furnstahl Adviser Professor Junko Shigemitsu Graduate Program in Professor Brian L. Winer Physics Abstract The recently discovered resonance X(3872) is interpreted as a loosely-bound S- wave charm meson molecule whose constituents are a superposition of the charm mesons D0D¯ ¤0 and D¤0D¯ 0. The unnaturally small binding energy of the molecule implies that it has some universal properties that depend only on its binding energy and its width. The existence of such a small energy scale motivates the separation of scales that leads to factorization formulas for production rates and decay rates of the X(3872). Factorization formulas are applied to predict that the line shape of the X(3872) differs significantly from that of a Breit-Wigner resonance and that there should be a peak in the invariant mass distribution for B ! D0D¯ ¤0K near the D0D¯ ¤0 threshold. An analysis of data by the Babar collaboration on B ! D(¤)D¯ (¤)K is used to predict that the decay B0 ! XK0 should be suppressed compared to B+ ! XK+. The differential decay rates of the X(3872) into J=Ã and light hadrons are also calculated up to multiplicative constants. If the X(3872) is indeed an S-wave charm meson molecule, it will provide a beautiful example of the predictive power of universality.
    [Show full text]
  • 06.08.2010 Yuming Wang the Charm-Loop Effect in B → K () L
    The Charm-loop effect in B K( )`+` ! ∗ − Yu-Ming Wang Theoretische Physik I , Universitat¨ Siegen A. Khodjamirian, Th. Mannel,A. Pivovarov and Y.M.W. arXiv:1006.4945 Workshop on QCD and hadron physics, Weihai, August, 2010 1 0 2 4 6 8 10 12 14 16 18 20 0 2.5 5 7.5 10 12.5 15 17.5 20 22.5 25 0 2 4 6 8 10 12 14 16 18 20 I. Motivation and introduction ( ) + B K ∗ ` `− induced by b s FCNC current: • prospectiv! e channels for the search! for new physics, a multitude of non-trival observables, Available measurements from BaBar, Belle, and CDF. Current averages (from HFAG, Sep., 2009): • BR(B Kl+l ) = (0:45 0:04) 10 6 ! − × − BR(B K l+l ) = (1:08+0:12) 10 6 : ! ∗ − 0:11 × − Invariant mass distribution and FBA (Belle,−2009): ) 2 1.2 /c 1 2 1 L / GeV 0.5 0.8 F -7 (10 0.6 2 0 0.4 1 0.2 dBF/dq 0.5 ) 0 FB 2 A /c 2 0.5 0 0.4 / GeV -7 0.3 (10 1 2 0.2 I A 0 0.1 dBF/dq 0 -1 0 2.5 5 7.5 10 12.5 15 17.5 20 22.5 25 0 2 4 6 8 10 12 14 16 18 20 q2(GeV2/c2) q2(GeV2/c2) Yu-Ming Wang Workshop on QCD and hadron physics, Weihai, August, 2010 2 q2(GeV2/c2) q2(GeV2/c2) Decay amplitudes in SM: • A(B K( )`+` ) = K( )`+` H B ; ! ∗ − −h ∗ − j eff j i 4G 10 H = F V V C (µ)O (µ) ; eff p tb ts∗ i i − 2 iX=1 Leading contributions from O and O can be reduced to B K( ) 9;10 7γ ! ∗ form factors.
    [Show full text]
  • Charm and Strange Quark Contributions to the Proton Structure
    Report series ISSN 0284 - 2769 of SE9900247 THE SVEDBERG LABORATORY and \ DEPARTMENT OF RADIATION SCIENCES UPPSALA UNIVERSITY Box 533, S-75121 Uppsala, Sweden http://www.tsl.uu.se/ TSL/ISV-99-0204 February 1999 Charm and Strange Quark Contributions to the Proton Structure Kristel Torokoff1 Dept. of Radiation Sciences, Uppsala University, Box 535, S-751 21 Uppsala, Sweden Abstract: The possibility to have charm and strange quarks as quantum mechanical fluc- tuations in the proton wave function is investigated based on a model for non-perturbative QCD dynamics. Both hadron and parton basis are examined. A scheme for energy fluctu- ations is constructed and compared with explicit energy-momentum conservation. Resulting momentum distributions for charniand_strange quarks in the proton are derived at the start- ing scale Qo f°r the perturbative QCD evolution. Kinematical constraints are found to be important when comparing to the "intrinsic charm" model. Master of Science Thesis Linkoping University Supervisor: Gunnar Ingelman, Uppsala University 1 kuldsepp@tsl .uu.se 30-37 Contents 1 Introduction 1 2 Standard Model 3 2.1 Introductory QCD 4 2.2 Light-cone variables 5 3 Experiments 7 3.1 The HERA machine 7 3.2 Deep Inelastic Scattering 8 4 Theory 11 4.1 The Parton model 11 4.2 The structure functions 12 4.3 Perturbative QCD corrections 13 4.4 The DGLAP equations 14 5 The Edin-Ingelman Model 15 6 Heavy Quarks in the Proton Wave Function 19 6.1 Extrinsic charm 19 6.2 Intrinsic charm 20 6.3 Hadronisation 22 6.4 The El-model applied to heavy quarks
    [Show full text]
  • Introduction to Flavour Physics
    Introduction to flavour physics Y. Grossman Cornell University, Ithaca, NY 14853, USA Abstract In this set of lectures we cover the very basics of flavour physics. The lec- tures are aimed to be an entry point to the subject of flavour physics. A lot of problems are provided in the hope of making the manuscript a self-study guide. 1 Welcome statement My plan for these lectures is to introduce you to the very basics of flavour physics. After the lectures I hope you will have enough knowledge and, more importantly, enough curiosity, and you will go on and learn more about the subject. These are lecture notes and are not meant to be a review. In the lectures, I try to talk about the basic ideas, hoping to give a clear picture of the physics. Thus many details are omitted, implicit assumptions are made, and no references are given. Yet details are important: after you go over the current lecture notes once or twice, I hope you will feel the need for more. Then it will be the time to turn to the many reviews [1–10] and books [11, 12] on the subject. I try to include many homework problems for the reader to solve, much more than what I gave in the actual lectures. If you would like to learn the material, I think that the problems provided are the way to start. They force you to fully understand the issues and apply your knowledge to new situations. The problems are given at the end of each section.
    [Show full text]
  • The Taste of New Physics: Flavour Violation from Tev-Scale Phenomenology to Grand Unification Björn Herrmann
    The taste of new physics: Flavour violation from TeV-scale phenomenology to Grand Unification Björn Herrmann To cite this version: Björn Herrmann. The taste of new physics: Flavour violation from TeV-scale phenomenology to Grand Unification. High Energy Physics - Phenomenology [hep-ph]. Communauté Université Grenoble Alpes, 2019. tel-02181811 HAL Id: tel-02181811 https://tel.archives-ouvertes.fr/tel-02181811 Submitted on 12 Jul 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. The taste of new physics: Flavour violation from TeV-scale phenomenology to Grand Unification Habilitation thesis presented by Dr. BJÖRN HERRMANN Laboratoire d’Annecy-le-Vieux de Physique Théorique Communauté Université Grenoble Alpes Université Savoie Mont Blanc – CNRS and publicly defended on JUNE 12, 2019 before the examination committee composed of Dr. GENEVIÈVE BÉLANGER CNRS Annecy President Dr. SACHA DAVIDSON CNRS Montpellier Examiner Prof. ALDO DEANDREA Univ. Lyon Referee Prof. ULRICH ELLWANGER Univ. Paris-Saclay Referee Dr. SABINE KRAML CNRS Grenoble Examiner Prof. FABIO MALTONI Univ. Catholique de Louvain Referee July 12, 2019 ii “We shall not cease from exploration, and the end of all our exploring will be to arrive where we started and know the place for the first time.” T.
    [Show full text]
  • Effective Field Theories of Heavy-Quark Mesons
    Effective Field Theories of Heavy-Quark Mesons A thesis submitted to The University of Manchester for the degree of Doctor of Philosophy (PhD) in the faculty of Engineering and Physical Sciences Mohammad Hasan M Alhakami School of Physics and Astronomy 2014 Contents Abstract 10 Declaration 12 Copyright 13 Acknowledgements 14 1 Introduction 16 1.1 Ordinary Mesons......................... 21 1.1.1 Light Mesons....................... 22 1.1.2 Heavy-light Mesons.................... 24 1.1.3 Heavy-Quark Mesons................... 28 1.2 Exotic cc¯ Mesons......................... 31 1.2.1 Experimental and theoretical studies of the X(3872). 34 2 From QCD to Effective Theories 41 2.1 Chiral Symmetry......................... 43 2.1.1 Chiral Symmetry Breaking................ 46 2.1.2 Effective Field Theory.................. 57 2.2 Heavy Quark Spin Symmetry.................. 65 2.2.1 Motivation......................... 65 2.2.2 Heavy Quark Effective Theory.............. 69 3 Heavy Hadron Chiral Perturbation Theory 72 3.1 Self-Energies of Charm Mesons................. 78 3.2 Mass formula for non-strange charm mesons.......... 89 3.2.1 Extracting the coupling constant of even and odd charm meson transitions..................... 92 2 4 HHChPT for Charm and Bottom Mesons 98 4.1 LECs from Charm Meson Spectrum............... 99 4.2 Masses of the charm mesons within HHChPT......... 101 4.3 Linear combinations of the low energy constants........ 106 4.4 Results and Discussion...................... 108 4.5 Prediction for the Spectrum of Odd- and Even-Parity Bottom Mesons............................... 115 5 Short-range interactions between heavy mesons in frame- work of EFT 126 5.1 Uncoupled Channel........................ 127 5.2 Two-body scattering with a narrow resonance........
    [Show full text]
  • Top, Beauty & Charm at the Lhec
    The LHeC project INT workshop – Science case for an EIC Seattle, WA, November 18, 2010 Olaf Behnke (DESY) ..Logo from the ongoing logo contest.. 1 Need for LHeC 27.5 GeV x 920 GeV ep HERA with integrated L~0.5 fb-1 was a high precision machine for QCD modest precision machine for electroweak physics Where could we go with a 20-150 GeV x 7 TeV e±p, also eA collider with integrated L~1-100 fb-1 ? 2 Lepton proton scattering experiments LHeC = highest energy and high lumi 3 LHeCPhysics grand and Range High mass 1-2 TeV r few times 10-20 m picture q Large x High precision partons in plateau of the LHC Talk Content: Accelerator Nuclear 1. Inclusive DIS & PDFs High Density Matter 2. Jets, c,b,t Structure 3. Low x, saturation & dynamics 4. EW and BSM 4 LHeC Accelerator options N I L p e Ring-Ring 4e pn px py Power Limit of 100 MW wall plug 11 E p N p 1.710 , p 3.8m, px( y) 1.8(0.5)m, M p “ultimate” LHC proton beam 11 ± N 10 m I L 8.21032cm 2s1 p e 60 GeV e beam 1.7 50mA px py I 0.35mA P[MW ](100 / E [GeV ])4 e e L = 2 1033 cm-2s-1 O(100) fb-1 5 LHeC Accelerator options 1 N 1 I L p e LINAC Ring 4 * e p 60 GeV “Circus Maximus” with N 1.7 1011, 3.8m,* 0.2m, 7000/0.94 p p Energy recovery: P=P /(1-η) N 1011 0.2 I /mA 0 L 8 1031cm 2s1 p e 1.7 * /m 1 β*=0.1m P / MW L = 1033 cm-2s-1 O(100) fb-1 Ie mA Ee /GeV 32 140 GeV LINAC few times 10 6 1.
    [Show full text]
  • Round Table: Flavour Anomalies in B → Sl+L− Processes
    EPJ Web of Conferences 137, 01001 (2017) DOI: 10.1051/ epjconf/201713701001 XIIth Quark Confinement & the Hadron Spectrum + Round table: Flavour anomalies in b s� �− processes → T. Blake1, M. Gersabeck2,a, L. Hofer3, S. Jäger4, Z. Liu5, and R. Zwicky6 1University of Warwick, Coventry, UK 2The University of Manchester, Manchester, UK 3Institut de Ciencies del Cosmos, Universitat de Barcelona, Barcelona, Spain 4University of Sussex, Brighton, UK 5Institute of High Energy Physics and Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences, Beijing, 100049, China 6University of Edinburgh, Edinburgh, UK Abstract. Precision measurements of flavour observables can provide powerful tests of many extensions of the Standard Model. This contribution covers a range of flavour + measurements of b s� �− transitions, several of which are in tension with the Stan- → dard Model of particle physics, as well as their theoretical interpretation. The basics of the theoretical background are discussed before turning to the main question of the field: whether the anomalies can be explained by QCD effects or whether they may be indicators of effects beyond the Standard Model. 1 Introduction Flavour physics has a long track record of discoveries that paved the way for advances in particle physics. In particular the discovery of B0 meson oscillations in 1987 [1] is a great example to demon- strate the potential of flavour physics to infer physics of high mass scales through precision measure- ments at low scales: the observed rate of oscillations was the first indication of the top quark being much heavier than the other five quark flavours. Precision flavour measurements at the LHC are sen- sitive to indirect effects from physics beyond the Standard Model (SM) at far greater scales than those accessible in direct searches.
    [Show full text]
  • A Study of Charm Quark Production in Beauty Quark Decays with the 0 PAL Detector at LEP
    A Study of Charm Quark Production in Beauty Quark Decays with the 0 PAL Detector at LEP by David Waller B.Sc., M.Sc. A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy Ottawa-Carleton Institute for Physics Department of Physics, Carleton University Ottawa, Ontario, Canada January, 2003 @copyright 2003, David ·waller National Library Bibliotheque nationale l+I of Canada du Canada Acquisitions and Acquisitions et Bibliographic Services services bibliographiques 395 Wellington Street 395, rue Wellington Ottawa ON K1A ON4 Ottawa ON K1A ON4 canada Csnada Your 6/e Voln> r8Mrence Our file Notre reMr- The author has granted a non­ L' auteur a accorde une licence non exclusive licence allowing the exclusive permettant a la National Library of Canada to Bibliotheque nationale du Canada de reproduce, loan, distnbute or sell reproduire, preter, distribuer ou copies of this thesis in microform, vendre des copies de cette these sous paper or electronic formats. la forme de microfiche/film, de reproduction sur papier ou sur format electronique. The author retains ownership of the L' auteur conseive la propriete du copyright in this thesis. Neither the droit d'auteur qui protege cette these. thesis nor substantial extracts from it Ni la these ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent etre imprimes reproduced without the author's ou autrement reproduits sans son pemnss1on. autorisation. 0-612~79467-9 Canada The undersigned hereby recommend to the Faculty of Graduate Studies and Research acceptance of the thesis, A Study of Charm Quark Production in Beauty Quark Decays with the OPAL detector at LEP submitted by David Waller, B.Sc., M.Sc.
    [Show full text]