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Lepton Dipole Moments Lepton Dipole Moments Adam West, YaleAdam University West Outline: Lepton Dipole Moments Adam West, PIC 2015 Outline: • Introduction • MDMs (g-2) • Motivation • Test of fundamental theories • Electron • Penning traps • Muon • Storage ring technique • Tau • Collider results • Neutrinos Lepton Dipole Moments Adam West, PIC 2015 Outline: • Introduction • MDMs (g-2) • Motivation • Test of fundamental theories • Electron • Penning traps • Muon • Storage ring technique • Tau • Collider results • Neutrinos • EDMs • Motivation • Tests of symmetries/theories • Electron • Atomic/molecular enhancement • Muon • Storage ring technique • Tau • Collider results Lepton Dipole Moments Adam West, PIC 2015 Outline: • Introduction • MDMs (g-2) • Motivation • Test of fundamental theories • Electron • Penning traps • Muon • Storage ring technique • Tau • Collider results • Neutrinos • EDMs • Motivation • Tests of symmetries/theories • Electron • Atomic/molecular enhancement • Muon • Storage ring technique • Tau • Collider results • Conclusion Lepton Dipole Moments Adam West, PIC 2015 Outline: • Introduction • MDMs (g-2) • Motivation • Test of fundamental theories • Electron • Penning traps • Muon • Storage ring technique • Tau • Collider results • Neutrinos • EDMs • Motivation • Tests of symmetries/theories • Electron • Atomic/molecular enhancement • Muon • Storage ring technique • Tau • Collider results • Conclusion All of these experiments exemplify precision measurement Lepton Dipole Moments Adam West, PIC 2015 Introduction: Lepton Dipole Moments Adam West, PIC 2015 Introduction: LHC: New physics through observations of new particles Lepton Dipole Moments Adam West, PIC 2015 Introduction: LHC: Dipole moments: New physics through observations of new New physics through observations of the particles effects of virtual particles Lepton Dipole Moments Adam West, PIC 2015 Introduction: LHC: Dipole moments: New physics through observations of new New physics through observations of the particles effects of virtual particles Mainly sensitive to strongly interacting particles Lepton Dipole Moments Adam West, PIC 2015 Introduction: LHC: Dipole moments: New physics through observations of new New physics through observations of the particles effects of virtual particles Mainly sensitive to strongly interacting Sensitive to weakly interacting particles particles Lepton Dipole Moments Adam West, PIC 2015 Introduction: LHC: Dipole moments: New physics through observations of new New physics through observations of the particles effects of virtual particles Mainly sensitive to strongly interacting Sensitive to weakly interacting particles particles Complementary approaches, allow discrimination Lepton Dipole Moments Adam West, PIC 2015 Introduction: EDMS: Lepton Dipole Moments Adam West, PIC 2015 Introduction: EDMS: Probes of new physics ml = Lepton mass dl = Lepton EDM φCP = CP-violating phase Lepton Dipole Moments Adam West, PIC 2015 Introduction: EDMS: Probes of new physics ml = Lepton mass dl = Lepton EDM φCP = CP-violating phase Lepton Dipole Moments Adam West, PIC 2015 Introduction: EDMS: Probes of new physics ml = Lepton mass dl = Lepton EDM φCP = CP-violating phase Lepton Dipole Moments Adam West, PIC 2015 Introduction: EDMS: Probes of new physics ml = Lepton mass dl = Lepton EDM φCP = CP-violating phase EDMs probe CP-violating new physics up to the TeV mass scale for 1-loop effects. Lepton Dipole Moments Adam West, PIC 2015 Introduction: EDMS: Probes of new physics ml = Lepton mass dl = Lepton EDM φCP = CP-violating phase EDMs probe CP-violating new physics up to the TeV mass scale for 1-loop effects. Electron EDM probes highest energies. Lepton Dipole Moments Adam West, PIC 2015 Introduction: EDMS: Probes of new physics ml = Lepton mass dl = Lepton EDM φCP = CP-violating phase EDMs probe CP-violating new physics up to the TeV mass scale for 1-loop effects. Electron EDM probes highest energies. Muon EDM more sensitive to some types of new physics. Lepton Dipole Moments Adam West, PIC 2015 Introduction: MDMs: ml = Lepton mass δal = MDM precision Lepton Dipole Moments Adam West, PIC 2015 Introduction: MDMs: Probes of new physics ml = Lepton mass δal = MDM precision Lepton Dipole Moments Adam West, PIC 2015 Introduction: MDMs: Probes of new physics ml = Lepton mass δal = MDM precision No CP-violation required, less sensitive than EDMs. Electron, muon, tau probing energy scales of ~ 10-100 GeV, 100 GeV, 0.1-1 GeV Lepton Dipole Moments Adam West, PIC 2015 Introduction: MDMs: Probes of new physics ml = Lepton mass δal = MDM precision No CP-violation required, less sensitive than EDMs. Electron, muon, tau probing energy scales of ~ 10-100 GeV, 100 GeV, 0.1-1 GeV Tests of the standard model Lepton Dipole Moments Adam West, PIC 2015 Introduction: MDMs: Probes of new physics ml = Lepton mass δal = MDM precision No CP-violation required, less sensitive than EDMs. Electron, muon, tau probing energy scales of ~ 10-100 GeV, 100 GeV, 0.1-1 GeV Tests of the standard model Electron g-2 relatively insensitive to electroweak contributions • Test of Standard Model’s most precise prediction • Best determination of α Lepton Dipole Moments Adam West, PIC 2015 Introduction: MDMs: Probes of new physics ml = Lepton mass δal = MDM precision No CP-violation required, less sensitive than EDMs. Electron, muon, tau probing energy scales of ~ 10-100 GeV, 100 GeV, 0.1-1 GeV Tests of the standard model Electron g-2 relatively insensitive to electroweak contributions • Test of Standard Model’s most precise prediction • Best determination of α Muon is heavier more sensitive to electroweak contributions Lepton Dipole Moments Adam West, PIC 2015 Introduction: MDMs: Probes of new physics ml = Lepton mass δal = MDM precision No CP-violation required, less sensitive than EDMs. Electron, muon, tau probing energy scales of ~ 10-100 GeV, 100 GeV, 0.1-1 GeV Tests of the standard model Electron g-2 relatively insensitive to electroweak contributions • Test of Standard Model’s most precise prediction • Best determination of α Muon is heavier more sensitive to electroweak contributions Lepton Dipole Moments Adam West, PIC 2015 MDMs Lepton Dipole Moments Adam West, PIC 2015 Motivation: 1Phys. Rev. Lett. 109, 111807 (2012), 2JHEP11 (2012) 113 Lepton Dipole Moments Adam West, PIC 2015 Motivation: Tests of SM: Comparisons against theory represent the most precise tests of SM predictions to date.1 1Phys. Rev. Lett. 109, 111807 (2012), 2JHEP11 (2012) 113 Lepton Dipole Moments Adam West, PIC 2015 Motivation: Tests of SM: Comparisons against theory represent the most precise tests of SM predictions to date.1 Discrepancies might indicate presence of internal structure or beyond SM physics. 1Phys. Rev. Lett. 109, 111807 (2012), 2JHEP11 (2012) 113 Lepton Dipole Moments Adam West, PIC 2015 Motivation: Tests of SM: Comparisons against theory represent the most precise tests of SM predictions to date.1 Discrepancies might indicate presence of internal structure or beyond SM physics. Multiple flavours are complementary, insight into lepton flavour violation. 1Phys. Rev. Lett. 109, 111807 (2012), 2JHEP11 (2012) 113 Lepton Dipole Moments Adam West, PIC 2015 Motivation: Tests of SM: Comparisons against theory represent the most precise tests of SM predictions to date.1 Discrepancies might indicate presence of internal structure or beyond SM physics. Multiple flavours are complementary, insight into lepton flavour violation. Fri. 9:05: Charged Lepton Flavour Physics Mark Lancaster 1Phys. Rev. Lett. 109, 111807 (2012), 2JHEP11 (2012) 113 Lepton Dipole Moments Adam West, PIC 2015 Electron g-2: Theory: 1PRL 109, 111807 (2012), 2PLB 734, 144 (2014), 3PRD 67, 073006 (2003), 4PRD 88, 053005 (2013) Lepton Dipole Moments Adam West, PIC 2015 Electron g-2: Theory: • Classical mechanics/non-relativistic QM: g e = 1 1PRL 109, 111807 (2012), 2PLB 734, 144 (2014), 3PRD 67, 073006 (2003), 4PRD 88, 053005 (2013) Lepton Dipole Moments Adam West, PIC 2015 Electron g-2: Theory: • Classical mechanics/non-relativistic QM: g e = 1 • Dirac combined QM and special relativity to show: ge = 2 1PRL 109, 111807 (2012), 2PLB 734, 144 (2014), 3PRD 67, 073006 (2003), 4PRD 88, 053005 (2013) Lepton Dipole Moments Adam West, PIC 2015 Electron g-2: Theory: • Classical mechanics/non-relativistic QM: g e = 1 • Dirac combined QM and special relativity to show: ge = 2 • Detailed (perturbative) QED calculations tell us: ge = 2.002319304363286 1PRL 109, 111807 (2012), 2PLB 734, 144 (2014), 3PRD 67, 073006 (2003), 4PRD 88, 053005 (2013) Lepton Dipole Moments Adam West, PIC 2015 Electron g-2: Theory: • Classical mechanics/non-relativistic QM: g e = 1 • Dirac combined QM and special relativity to show: ge = 2 • Detailed (perturbative) QED calculations tell us: ge = 2.002319304363286 ‘Anomalous magnetic moment’: 1PRL 109, 111807 (2012), 2PLB 734, 144 (2014), 3PRD 67, 073006 (2003), 4PRD 88, 053005 (2013) Lepton Dipole Moments Adam West, PIC 2015 Electron g-2: Theory: • Classical mechanics/non-relativistic QM: g e = 1 • Dirac combined QM and special relativity to show: ge = 2 • Detailed (perturbative) QED calculations tell us: ge = 2.002319304363286 ‘Anomalous magnetic moment’: Calculations of ae draw from many aspects of SM: 1PRL 109, 111807 (2012), 2PLB 734, 144 (2014), 3PRD 67, 073006 (2003), 4PRD 88, 053005 (2013) Lepton Dipole Moments Adam West, PIC 2015 Electron g-2: Theory: • Classical mechanics/non-relativistic QM: g e = 1 • Dirac combined QM and special relativity to show: ge = 2 • Detailed (perturbative) QED calculations tell us: ge = 2.002319304363286
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