LFV Muon Dcays and a Nw Exprimnt to Sarch for μ (Mu3) BLV 2013 Workshop April 8-12, 2013 André Schöning for th Mu3 Collaboration 1
History of LFV Dcay xprimnts upgrad Mu2/Comt 2
LFV Muon Dcays: Exprimntal Situation μ+ γ μ- N - N Al μ+ - 13+ - μ- μ+ μ+ γ - MEG (PSI) SINDRUM II (PSI) B(μ+ γ) 5.7 10-13 (2013) B(μ Au Au) 7 10-13 (2006) SINDRUM (PSI) B(μ+ -) 10-12 (1988) running 3
LFV Muon Dcays in th SM μ+ γ μ- N - N Al μ+ - 13+ - μ- μ+ μ+ γ - SM: LFV loops Al branching ratios supprssd by (Δ m2ν )2 50 10 m4w 4
LFV Muon Dcays in SUSY μ+ γ μ- N - N Al 13+ μ- μ+ μ+ - μ+ γ - SUSY loops Al cohrnt convrsion in nuclus fild for Q2(γ*)~0 5 supprssd by xtra vrtx with rspct to μ+ γ
LFV Muon Dcays from SUSY loops μ+ γ μ- N - N Al 13+ μ- μ+ μ+ - μ+ γ - SUSY loops Al cohrnt convrsion in supprssd by ~1/150 1. SUSY modls lik many othr BSM modls induc naturally LFV nuclus fild for Q2(γ )~0 with rspct to μ+ γ 6
LFV Muon Dcays from SUSY loops μ+ γ μ- N - N Al 13+ μ- μ+ μ+ - μ+ γ - SUSY loops Al cohrnt convrsion in supprssd by ~1/150 2. LFV in μ γ implisnuclus LFV fild in both μn N and μn for Q2(γ )~0 with rspct to μ+ γ 7
LFV Tr Diagrams μ+ γ μ- N - N Al μ+ - 13+ - μ- μ+ μ+ γ q q LQ μ not allowd.g. Lptoquarks 8 xtra Z', LFV Higgs, tc.
Modl Indpndnt Comparison dipol couplings q arxiv:1211.7019 μqq contact IA q μ conv. μ q q μ μ+ + γ μ B( μ ) < 10-12 2.4 10-12 κ κ 0 κ = modl paramtr Λ = common ffctiv mass scal Effctiv clfv Lagrangian: L= mμ 2 Λ (1+κ) 9 H dipol + μ ν, qq κ J ν J 2 Λ (1+κ)
Exampl: Higgs Triplt Modls M.Kakizaki t al., Phys.Ltt. B566 210, 2003 Motivatd by Lft-Right Symmtric Modls triplt Higgs Daya Rno, Doubl Chooz M =Bay, 200 GV ν νµ ντ H, H++ μ + loop diagrams rlatd to nutrino masss ( v mass pattrn) 10
Exampl: Higgs Triplt Modls II M.Kakizaki t al., Phys.Ltt. B566 210, 2003 Motivatd by Lft-Right Symmtric Modls M = 200 GV M = 200 GV 4 A Br 4 M 11 A= trilinar coupling (25 V)
LFV SM - Higgs Couplings Framwork R. Harnik, J. Kopp J, Zupan [arxiv:1206.6497] LFV dcays of SM Higgs: LFV muon dcay: ~ LHC and muon dcay xpr. ar largly complmntarity! 12
Th Z-Pnguin Diagram in μ+ μ+ γ μ Z μ photon pnguin Z - pnguin from dimnsional analysis: Br 5 μ 4 m Br Λ 5 μ 4 Z m m 4 f (Λ ) dominats if Λ >> mz 13
Th Z-Pnguin Diagram in μ+ μ+ γ μ Z μ photon pnguin Z - pnguin from dimnsional analysis: Br 5 μ 4 m Br Λ 5 μ 4 Z m m 4 f (Λ ) no dcoupling in many modls! 14
Many Rcnt Paprs on/with Z-pnguin Hirsch t al., Enhancing li 3lj with th Z0-pnguin [arxiv:1202.1825] X Hirsch t al., Phnomnology of th minimal suprsymmtric U(1)B L U (1)R xtnsion of th standard modl [arxiv:1206.3516] dl Aguila t al., Lpton flavor violation in th Simplst Littl Higgs modl [arxiv:1101.2936] Drinr at al., Nw bounds on trilinar R-parity violation from lpton flavor violating obsrvabls [arxiv:1204.5925] X Abada t al., Enhancing lpton flavour violation in th suprsymmtric invrs ssaw byond th dipol contribution [arxiv:1206.6497] Ilakovac t al., Chargd Lpton Flavour Violation in Suprsymmtric Low-Scal Ssaw Modls [arxiv:1212.5939] Aristizabal Sirra t al., Minimal lpton flavor violating ralizations of minimal ssaw modls [arxiv:1205.5547] 15
Hirsch t al., Phnomnology of th minimal suprsymmtric U(1)B L U (1)R xtnsion of th standard modl [arxiv:1206.3516] MSSM Modl with havy right-handd nutrino and Z' dcoupling! m0 = 800 GV, M1/2 = 1200 GV, tan β = 10, A0 = 0 vr = 10 TV, tan βr = 1.05, μr = 500 GV, mar = 1000 GV. 16
Abada t al., Enhancing lpton flavour violation in th suprsymmtric invrs ssaw byond th dipol contribution [arxiv:1206.6497] B(μ+ -) Invrs Ssaw Modl LFV couplings fixd by nutrino mass matrix Z pnguin dashd lins rprsnt intrfrnc trms γ h + box Non-dcoupling bhaviour of Z-pnguin contribution Not μ+ - dominats ovr μ+ γ for m0> 1 TV 17
LFV Muon Dcays: Exprimntal Situation μ+ γ μ- N - N Al μ- μ+ - μ+ γ 13+ μ+ - - 18
LFV Muon Dcays: Exprimntal Situation μ+ γ μ- N - N Al 13+ μ- μ+ 2-body dcay mono-nrgtic,γ back-back topology - μ+ γ Kinmatics Kinmatics μ+ - Kinmatics quasi 2-body dcay mono-nrgtic lctron singl particl dtctd 19 Kinmatics 3-body dcay invariant mass constraint Σ p = 0 i
LFV Muon Dcays: Exprimntal Situation μ+ γ μ- N - N Al μ- μ+ Kinmatics Kinmatics 2-body dcay mono-nrgtic,γ back-back topology Backgrounds Backgrounds accidntal BG - μ+ γ 13+ μ+ - Kinmatics 2-body dcay mono-nrgtic lctron singl particl dtctd Kinmatics 3-body dcay invariant mass constraint Σ p = 0 i Backgrounds dcay in orbit (DIO) anti-protons (capturd) pion dcays Backgrounds radiativ dcay accidntal BG 20
LFV Muon Dcays: Exprimntal Situation μ+ γ μ- N - N Al μ- μ+ Kinmatics Kinmatics 2-body dcay mono-nrgtic,γ back-back topology Backgrounds Backgrounds accidntal BG rquirs continus bam - μ+ γ 13+ μ+ - Kinmatics 2-body dcay mono-nrgtic lctron singl particl dtctd Kinmatics 3-body dcay invariant mass constraint Σ p = 0 i Backgrounds dcay in orbit (DIO) anti-protons pion dcays Backgrounds radiativ dcay accidntal BG rquirs pulsd bam 21 rquirs continus bam
μ N N Convrsion Exprimnts Signatur: E = 105 MV ndpoint rgion Czarncki t al. 1106.4756v2 without rcoil ffct with rcoil ffct signal good nrgy(momntum) rsolution is crucial! almost BG fr procss JPARC: DM Rμ ~ 10-14 by ~2015 COMET Rμ ~ 10-16 by ~2020 PRISM Rμ ~ <10-16 by >2020 Frmilab: Mu2 Exprimnt Rμ ~ 10-17 - 10-16 22
Mu2 Exprimnt (Frmilab) talk by R.Ehrlich Concnptual Dsign Rport arxiv:1211.7019 Modifications 8 GV Proton Boostr rcyclr dbunchr nw muon transport lin costs 200-300 M$ collaborations ~200 mmbrs stopping targt hlical tracks in straw tubs calorimtr for triggr and PID start opration ~2020 xpctd snsitivity: Rμ ~ 10-17 - 10-16 23
MEG Exprimnt at PSI talk by G.Cavoto signatur: positron-muon back-to back in opration sinc 2009 Main rquirmnts: good nrgy (momntum) rsolution good spatial (angular) rsolution good timing 24
MEG Exprimnts at PSI Rsult from 2012 (90% CL): BR(μ+ γ) < 2.4 10-12 Improvd Analysis: talk by G.Cavoto Nw combind rsult (arxiv:1303.9754) Tracking using Kalman filtr Bttr limination of pil-up Analysis of nw 2011 data st Multivariat analysis of 5 variabls (E,Eγ, Θγ, Φγ, tγ ) 25
Mu3 Exprimnt Sarch for μ at PSI + + + - DPNC Gnva Univrsity Physics Institut, Univrsity Hidlbrg KIP, Univrsity Hidlbrg ZITI Mannhim, Univrsity Hidlbrg Paul Schrrr Institut Physics Institut, Univrsity Zurich Institut for Particl Physics, ETH Zurich projct approvd in Jan 2013 Aiming for a snsitivity of BR(μ ) < 10-15 (phas I) BR(μ ) < 10-16 (phas II) bfor nd of dcad 26
Lpton Flavor Violating Dcay: μ+ Exotic Physics loop diagrams tr diagram Suprsymmtry Higgs Triplt Modl Littl Higgs Modls Nw Havy Vctor bosons (Z') Ssaw Modls Extra Dimnsions (KK towrs) GUT modls (Lptoquarks) many othr modls 27
Lpton Flavor Violating Dcay: μ+ Exotic Physics loop diagrams tr diagram Suprsymmtry Higgs Triplt Modl Littl Higgs Modls Nw Havy Vctor bosons (Z') Ssaw Modls Extra Dimnsions (KK towrs) GUT modls (Lptoquarks) many othr modls 28
Modl Indpndnt Comparison μ μ contact IA μ μ B( μ ) < 10-12 κ 0 κ Effctiv clfv Lagrangian: L= mμ 2 Λ (1+ κ) H dipol ν, + 2 κ J μ J ν Λ (1+ κ) 29 κ = paramtr Λ = common ffctiv mass scal
Modl Indpndnt Comparison μ μ contact IA μ μ B( μ ) < 10-12 κ 0 κ B(μ+ -) B(μ γ) + + B(μ+ -) ~ 0.006 B(μ γ) + 30 + =
Backgrounds Irrducibl BG: radiativ dcay with intrnal convrsion - ν ν B(μ+ - - νν) = 3.4 10-5 i i 31 E i = mμ p i = 0
Backgrounds Irrducibl BG: radiativ dcay with intrnal convrsion - ν missing nrgy from two nutrinos stply falling! ν B(μ+ R.M.Djilkibav, R.V.Konoplich PRD79 (2009) - νν) = 3.4 10-5 vry good momntum + total nrgy rsolution rquird! 32
Accidntal Backgrounds Ovrlays of two normal muon dcays with a (fak) lctron Elctrons from: Bhabha scattring, photon convrsion, mis-rconstruction Nd xcllnt: Vrtx rsolution Timing rsolution Kinmatic rconstruction 33
Th Targt Sprad muon dcays in spac and tim DC Muon bam (PSI) about 4000 muons rsting on targt at sam tim larg stopping targt good vrtxing and timing rsolution rquird.g. Sindrum-lik xtndd targt hollow doubl con (.g. 30-80 µm Al) 34
Kinmatic Rsolution + Multipl Scattring Muon dcay: lctrons in low momntum rang p < 53 MV/c limitd hit rsolution rgim Multipl scattring is dominant! Nd thin, fast and high rsolution dtctors (tracking + tim of flight) opratd at high rat 109/s Θ MS 1 P X / X0 mutipl scattring rgim 35
Silicon Pixl Dtctor I.Pric, P. Fischr t al., NIM A 582 (2007) 876 (ZITI Mannhim, Uni Hidlbrg) transistor logic mbddd in N-wll ( smart diod array ) Tchnology Choic High Voltag Monolithic Activ Pixl Snsors (HV-MAPS) high prcision pixls 80 x 80 μm2 can b thinnd down to ~30 μm (~ 0.0004 X0) low production costs (standard HV-CMOS procss, 60-80 V) activ snsors small RO bandwidth, no bump bonding rquird triggrlss and fast radout (LVDS link intgratd) low powr 36
Mchanical Prototyps for Pixl Trackr MuPix3 chip Ultra-thin dtctor mock-up: sandwich of 25 µm Kapton and 50/100 µm glass (instad of Si) 50 mu silicon wafr Sandwich X 0.1% X0 pr layr possibl 37
Mu3 Exprimntal Proposal 38
Mu3 Baslin Dsign 39
Mu3 Baslin Dsign 40
Mu3 Baslin Dsign 41
Mu3 Baslin Dsign 42
Mu3 Baslin Dsign 43
Mu3 Baslin Dsign 44
Mu3 Baslin Dsign Long cylindr! not to scal! ~150 cm ~15 cm 45
Mu3 Baslin Dsign Long cylindr! not to scal ~150 cm ~15 cm B = 1 Tsla 46
Mu3 Baslin Dsign Long cylindr! not to scal ~150 cm ~15 cm B = 1 Tsla Gomtrical accptanc ~70 % for μ+ - dcay 47
Timing 48
Pixl Dtctor: Radout Frams @ 20 MHz 100 muon dcays @ rat 2 109 muon stops/s 50 ns snapshot 49
Pixl: Radout Frams 50 ns 100 muon dcays @ rat 2 109 muon stops/s Additional Tim of Flight (ToF) dtctors rquird < 1ns 50
Mu3 Tim of Flight Systm not to scal ~100 ps 200-300 ns Scintillating tils Scintillating fibrs 51
Invariant Mass Rsolution of Signal Phas IA: rat ~ 2 107 muons/s Phas IB: rat ~ 2 108 muons/s Phas II: rat ~ 2 109 muons/s 52
Snsitivity Study Phas IA: Phas II: rat 2 107 muons/s rat ~ 2 109 muons/s signal signal BG BG μ νν 53
PSI Facility for Mu3 X HiMB X Phas II (>2017): >109 muons/s Phas I (2015+): ~108 muons/s 54
π5 Bamlin (Phas I) MEG and Mu3 could co-xist if MEG is to b upgradd MEG muon rats of 1.4 108/s achivd in past rat of 108/s muons ndd to rach B( μ+ - ) ~ 2 10-15 (90%CL) 55
High Intnsitiy Muon Bamlin (Phas II) HiMB =High Intnsity Muon Bamlin Muon rats in xcss of 1010 pr scond in bam phas accptanc possibl 2 109 muons/s ndd to rach ultimat goal of B( μ+ - ) < 10-16 Not bfor 2017 56
Snsitivity Projction 2 107 /s 1 108 /s 57 2 109 /s
Conclusions Chargd LFV almost unavoidabl in BSM (GUT) modls and wll motivatd Nw ra of muon dcay xprimnts sarching for chargd LFV has startd Svral projcts aiming for snsitivitis of 10-16 or vn byond! Exprimnts ar wll motivatd and complimntary to ach othr and to LHC 1st confrnc on Chargd Lpton Flavor Violation, 6.-8. May, Lcc, Italy 58
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