New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw...

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Andre Schöning, Mu3e Collaboration 1 PSI, Open Users Meeting, January 15-16, 2013 New Experimental Search for μ→eee New Experimental Search for μ→eee Paul Scherrer Institut Open Users Meeting BV44 January 16, 2013 André Schöning for the Mu3e Collaboration

Transcript of New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw...

Page 1: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 1 PSI, Open Users Meeting, January 15-16, 2013

New Experimental Search for μ→eee New Experimental Search for μ→eee

Paul Scherrer Institut

Open Users Meeting BV44

January 16, 2013

André Schöning for the Mu3e Collaboration

Page 2: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 2 PSI, Open Users Meeting, January 15-16, 2013

Experimental GoalExperimental Goal

search for the LFV decay:

μ+ → e+e+e-

with a sensitivity of: B(μ+ → e+e+e-) ≤ 10-16

μ+

e-

e+

e+

τ(μ→eee)

≥ 700 years (τμ = 2.2 µs)

predicted by SM: B( μ+ → e+e+e- ) << 10- 50

Page 3: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 3 PSI, Open Users Meeting, January 15-16, 2013

Lepton Flavor Violating Decay: μ+ →e+e+e- Lepton Flavor Violating Decay: μ+ →e+e+e-

Exotic Physics

Supersymmetry

Little Higgs Models

Seesaw Models

GUT models (Leptoquarks)

many other models

loop diagrams tree diagram

Higgs Triplet Model

New Heavy Vector bosons (Z')

Extra Dimensions (KK towers)

Page 4: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 4 PSI, Open Users Meeting, January 15-16, 2013

μ+ → e+e+e-

μ+ → e+γ

new LFV mediator

μ eμ

μ e

eeee

Motivation μ+ →e+e+e- Motivation μ+ →e+e+e-

photon penguin

photon penguin

Page 5: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 5 PSI, Open Users Meeting, January 15-16, 2013

L =mμ

Λ2(1+ κ)

H dipole + κΛ

2(1+ κ)

J νeμ J ν , ee

Effective cLFV Lagrangian:

ee

μ e

ee

Model Independent ComparisonModel Independent Comparison

Λ

κ

= common effective mass scale

= parameter

μ eμ

B( μ →eee ) < 10-12

κ → 0 κ → ∞

Page 6: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 6 PSI, Open Users Meeting, January 15-16, 2013

ee

μ e

ee

Model Independent ComparisonModel Independent Comparison

μ eμ

κ → 0 κ → ∞

B(μ+ → e+e+e-)

B(μ+ → e+γ)~ 0.006

B(μ+ → e+e+e-)

B(μ+ → e+γ)= ∞

B( μ →eee ) < 10-12

Page 7: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 7 PSI, Open Users Meeting, January 15-16, 2013

μ+ → e+e+e-

μ+ → e+γ

photon penguin new LFV mediator

μ eμ

μ e

eeee

Z' (H, KK)

The μ+ →e+e+e- Tree Diagram The μ+ →e+e+e- Tree Diagram

photon penguin

Page 8: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 8 PSI, Open Users Meeting, January 15-16, 2013

νe νµ ντ

M.Kakizaki et al., Phys.Lett. B566 210, 2003

Example: Higgs Triplet ModelsExample: Higgs Triplet ModelsExample: Higgs Triplet ModelsExample: Higgs Triplet Models

Motivated by Left-Right Symmetric Models

Daya Bay, Reno, Double Choozee

H, H++

related to neutrino masses (→ v mass pattern)

M = 200 GeV

triplet Higgs

Page 9: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 9 PSI, Open Users Meeting, January 15-16, 2013

M.Kakizaki et al., Phys.Lett. B566 210, 2003

Motivated by Left-Right Symmetric Models

Example: Higgs Triplet Models IIExample: Higgs Triplet Models II

M = 200 GeV M = 200 GeV

Br ∝A4

M4A= trilinear coupling (25 eV)

Page 10: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 10 PSI, Open Users Meeting, January 15-16, 2013

μ+ → e+e+e-

μ+ → e+γ

μ eμ

μ e

ee

The μ+ →e+e+e- Z-Penguin DiagramThe μ+ →e+e+e- Z-Penguin Diagram

μ e

ee

γ

γ

Z

photon penguinphoton penguin

photon penguin Z - penguin

Page 11: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 11 PSI, Open Users Meeting, January 15-16, 2013

μ+ → e+e+e-

μ e

ee

μ e

ee

γ Z

Br ∝mμ5

Λ4

from dimensional analysis:

Br ∝mμ5

mZ4 f (Λ4)

dominates if Λ >> mZ

The μ+ →e+e+e- Z-Penguin DiagramThe μ+ →e+e+e- Z-Penguin Diagram

photon penguin Z - penguin

Page 12: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 12 PSI, Open Users Meeting, January 15-16, 2013

μ+ → e+e+e-

μ e

ee

μ e

ee

γ Z

Br ∝mμ5

Λ4

from dimensional analysis:

Br ∝mμ5

mZ4 f (Λ4)

no decoupling in many models!

The μ+ →e+e+e- Z-Penguin DiagramThe μ+ →e+e+e- Z-Penguin Diagram

photon penguin Z - penguin

Page 13: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 13 PSI, Open Users Meeting, January 15-16, 2013

Many Recent Papers on/with Z-penguinMany Recent Papers on/with Z-penguin

Hirsch et al., Enhancing li → 3l

j with the Z0-penguin [arXiv:1202.1825]

Hirsch et al., Phenomenology of the minimal supersymmetric U(1)B−L

× U (1)R

extension of the standard model [arXiv:1206.3516]

del Aguila et al., Lepton flavor violation in the Simplest Little Higgs model [arXiv:1101.2936]

Dreiner at al., New bounds on trilinear R-parity violation from lepton flavor violating observables [arXiv:1204.5925]

Abada et al., Enhancing lepton flavour violation in the supersymmetric inverse seesaw beyond the dipole contribution [arXiv:1206.6497]

Ilakovac et al., Charged Lepton Flavour Violation in Supersymmetric Low-Scale Seesaw Models [arXiv:1212.5939]

Aristizabal Sierra et al., Minimal lepton flavor violating realizations of minimal seesaw models [arXiv:1205.5547]

X

X

Page 14: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 14 PSI, Open Users Meeting, January 15-16, 2013

Hirsch et al., Phenomenology of the minimal supersymmetric U(1)B−L

× U (1)R

extension of the standard model [arXiv:1206.3516]

MSSM Model with heavy right-handed neutrino and Z'

m0 = 800 GeV, M

1/2 = 1200 GeV, tan β = 10, A

0 = 0

vR = 10 TeV, tan β

R = 1.05, μ

R = −500 GeV, m

AR = 1000 GeV.

decoupling!

Page 15: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 15 PSI, Open Users Meeting, January 15-16, 2013

Hisana et al., hep-ph/9510309

Supersymmetric Seesaw MechanismSupersymmetric Seesaw Mechanism

box diagrams

Z-penguin

photon

Page 16: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 16 PSI, Open Users Meeting, January 15-16, 2013

μ+ → e+e+e-

μ e

ee

μ e

ee

γ Z

Motivation μ+ →e+e+e- Motivation μ+ →e+e+e-

Higgs-penguin

μ e

ee

H

box diagramμ e

ee

photon penguin Z - penguin

Page 17: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 17 PSI, Open Users Meeting, January 15-16, 2013

Abada et al., Enhancing lepton flavour violation in the supersymmetric inverse seesaw beyond the dipole contribution [arXiv:1206.6497]

Z

γ

h + box

B(μ

+ →

e+e

+e

- )

dashed lines represent interference terms

Non decoupling behaviour of Z-penguin contribution

LFV couplings fixed by neutrino mass matrix

Note μ+ → e+e+e- dominates over μ+ → e+ γ for m0 > 1 TeV

Inverse Seesaw Model

Page 18: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 18 PSI, Open Users Meeting, January 15-16, 2013

ee

μ e

ee

Model Independent ComparisonModel Independent Comparison

μ eμ

κ = 0 κ = ∞

γ

Z

Z-penguin enhanced by factor 10

Improvement of existing SINDRUM limit by 2 orders of magnitude is relevant!

Page 19: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 19 PSI, Open Users Meeting, January 15-16, 2013

Experimental SituationExperimental Situation

Page 20: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 20 PSI, Open Users Meeting, January 15-16, 2013

BackgroundsBackgrounds

e+

e+e-

∑iE i = mμ

∑ip⃗i = 0

Irreducible BG: radiative decay with internal conversion

e+

e+e-

ν

ν

B(μ+ → e+e+e- νν) = 3.4 ·10- 5

Page 21: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 21 PSI, Open Users Meeting, January 15-16, 2013

BackgroundsBackgrounds

Irreducible BG: radiative decay with internal conversion

e+

e+e-

ν

ν

missing energy from two neutrinos

steeply falling!R.M.Djilkibaev,R.V.Konoplich PRD79 (2009)

B(μ+ → e+e+e- νν) = 3.4 ·10- 5

Page 22: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 22 PSI, Open Users Meeting, January 15-16, 2013

BackgroundsBackgrounds

Irreducible BG: radiative decay with internal conversion

e+

e+e-

ν

ν

B(μ+ → e+e+e- νν) = 3.4 ·10- 5

very good momentum + total energy resolution required!

Page 23: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 23 PSI, Open Users Meeting, January 15-16, 2013

Accidental BackgroundsAccidental Backgrounds

Overlays of two normal muon decays with a (fake) electron

Electrons from: Bhabha scattering, photon conversion, mis-reconstruction

Need excellent: vertex resolution timing resolution kinematic reconstruction

Page 24: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 24 PSI, Open Users Meeting, January 15-16, 2013

The Target The Target

Spread muon decays

in space and time

DC Muon beam (PSI)

about 4000 muons restingon target at same time

large stopping target

good vertexing and timingresolution required

e.g. Sindrum-like extended target

hollow double cone (e.g. 30-80 µm Al)

Page 25: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 25 PSI, Open Users Meeting, January 15-16, 2013

Kinematic Resolution + Multiple ScatteringKinematic Resolution + Multiple Scattering

ΘMS ∼1P

√X /X0

Muon decay:

→ electrons in low momentum range p < 53 MeV/c

Multiple scattering is dominant!

Need thin, fast and high resolution

detectors (tracking + time of flight)

mutiple scatteringregime

limited hit resolution regime

Page 26: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 26 PSI, Open Users Meeting, January 15-16, 2013

Experimental ProposalExperimental Proposal

Page 27: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 27 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

Page 28: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 28 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

Page 29: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 29 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

Page 30: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 30 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

Page 31: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 31 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

Page 32: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 32 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

Page 33: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 33 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

Long cylinder!

~15 cm

~180 cm

not to scale!

Page 34: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 34 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

Long cylinder!

~15 cm

~180 cm

not to scale

B = 1 Tesla

Page 35: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 35 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

Geometrical acceptance ~70 % for μ+ → e+e+e- decay

Long cylinder!

~15 cm

~180 cm

not to scale

B = 1 Tesla

Page 36: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 36 PSI, Open Users Meeting, January 15-16, 2013

50 mu silicon wafer

Ultra-thin detector mock-up:sandwich of 25 µm Kapton®

and 50/100 µm glass (instead of Si)

Mechanical Prototypes

MuPix3chip

Sandwich

Page 37: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 37 PSI, Open Users Meeting, January 15-16, 2013

Silicon Pixel Detector

Central barrel two inner layers two outer layers

Mounting Device

long barrel design

cooling by He-gas

Page 38: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 38 PSI, Open Users Meeting, January 15-16, 2013

Silicon Pixel Detector

Technology Choice

High Voltage Monolithic Active Pixel Sensors (HV-MAPS)

high precision → pixels 80 x 80 μm2

can be “thinned” down to ~30 μm (~ 0.0004 X0)

low production costs (standard HV-CMOS process, 60-80 V)

active sensors → small RO bandwidth, no bump bonding required

triggerless and fast readout (LVDS link integrated)

low power

I.Peric, P. Fischer et al., NIM A 582 (2007) 876 (ZITI Mannheim, Uni Heidelberg)

transistor logic embedded in N-well(“smart diode array”)

Page 39: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 39 PSI, Open Users Meeting, January 15-16, 2013

Pixel Detector Tests

prototype 180 nm(MuPix2)

MuPix2 at CERN beam test

MuPix2 characterization in lab

Signal from 55Fe

Noise from LED injection pulse scan

CERN Test Beam: 180 GeV pions low bias voltage V

bias=56 V

threshold Vth=0.9 V

~95% single hit efficiency (preliminary)

Lab: Ubias

= 60 V

Peerevoort, Heidelberg

Page 40: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 40 PSI, Open Users Meeting, January 15-16, 2013

TimingTiming

Page 41: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 41 PSI, Open Users Meeting, January 15-16, 2013

Pixel Detector: Readout Frames @ 20 MHz

100 muon decays @ rate 2 · 109 muon stops/s

50 ns snapshot

Page 42: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 42 PSI, Open Users Meeting, January 15-16, 2013

Pixel: Readout Frames 50 ns

100 muon decays @ rate 2 · 109 muon stops/s

Additional Time of Flight (ToF) detectors required < 1ns

Page 43: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 43 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

not to scale

Scintillating tiles

200-300 ns~100 ps

Scintillating fibers

Page 44: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 44 PSI, Open Users Meeting, January 15-16, 2013

Scintillating Fiber Tracker

high spatial resolution (matching with silicon hits)

scintillating fibers Ø = 250 μm fibers (3 layers)

photosensorHamamatsu MPPC arrrays (SiPM)high gain >105, high frequency > 1MHzalternative SiPM?

time resolution <1 ns optical cross talk? prototypes in preparation

SiPm Array Hamamatsu MPPC 5883

in collaboration with EPFL (Nakada et al.)

University Geneva

Page 45: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 45 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Baseline Design

not to scale

Scintillating tiles

~1ns~100 ps

Scintillating fibers

Page 46: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 46 PSI, Open Users Meeting, January 15-16, 2013

Scintillating Tile Detector

Timing information helps to reduce accidental backgrounds

scintillating tiles of size ~ 1 cm2

timing resolution of about 100 ps photosensors (SiPM)

rate @ Phase II

Simulation Phase II

RMS=75 ps

time resolution

Page 47: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 47 PSI, Open Users Meeting, January 15-16, 2013

Data Acquisition

Central pixel detectors (Phase I) frontend data rate of 90 Gbit/s

Full pixel detector (Phase II) frontend data rate of 1500 Gbit/s

Online event reconstruction using Graphics Processing Units (GPUs)

Logging rate ~50-100 MB/s

Page 48: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 48 PSI, Open Users Meeting, January 15-16, 2013

Simulation

full GEANT4 simulation used

Page 49: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 49 PSI, Open Users Meeting, January 15-16, 2013

Reconstruction

Phase IA: rate ≤ 107 muons/s

Phase IB: rate ~ 108 muons/s

Phase II: rate ~ 109 muons/s

only central Pixel

+ inner recurl stations+ time of flight system

+ outer recurl stations+ outer tiles

Page 50: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 50 PSI, Open Users Meeting, January 15-16, 2013

3D Track Reconstruction

Phase IA: rate ≤ 107 muons/s

Phase IB: rate ~ 108 muons/s

Phase II: rate ~ 109 muons/s

Number Linked Hits

Page 51: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 51 PSI, Open Users Meeting, January 15-16, 2013

Invariant Mass Resolution of Signal

Phase IA: rate ~ 2 ∙ 107 muons/s

Phase IB: rate ~ 2 ∙ 108 muons/s

Phase II: rate ~ 2 ∙ 109 muons/s

mass resolution

Page 52: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 52 PSI, Open Users Meeting, January 15-16, 2013

Phase IA: rate ≤ 2 ∙ 107 muons/s

Sensitivity Study

Phase II: rate ~ 2 ∙ 109 muons/s

BG

μ→eeeνν

signal

Page 53: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 53 PSI, Open Users Meeting, January 15-16, 2013

Sensitivity Projection

2 ∙ 107 /s 1 ∙ 108 /s 2 ∙ 109 /s

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Andre Schöning, Mu3e Collaboration 54 PSI, Open Users Meeting, January 15-16, 2013

X

X

Phase I (2015+): ~108 muons/s Phase II (>2017): >109 muons/s

PSI Facility for Mu3e

HiMB

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Andre Schöning, Mu3e Collaboration 55 PSI, Open Users Meeting, January 15-16, 2013

πe5 Beamline (Phase I)MEG and Mu3e could co-exist if MEG is to be upgraded

MEG

muon rates of 1.4 · 108/s achieved in past

rate of 108/s needed to reach B( μ+ →e+e+e- ) ~ 2 ·10 -15 (90%CL) in 3 years

Page 56: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 56 PSI, Open Users Meeting, January 15-16, 2013

High Intensitiy Muon Beamline (Phase II)

Muon rates in excess of 1010 per second in beam phase acceptance possible

2 · 109 muons/s needed to reach ultimate goal of B( μ+ →e+e+e- ) < 10-16

Not before 2017

HiMB =High Intensity Muon Beamline

Page 57: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 57 PSI, Open Users Meeting, January 15-16, 2013

Mu3e Proto-Collaboration

DPNC Geneva University

Physics Institute, University Heidelberg

KIP, University Heidelberg

ZITI Mannheim, University Heidelberg

Paul Scherrer Institute

Physics Institute, University Zurich

Institute for Particle Physics, ETH Zurich

Page 58: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 58 PSI, Open Users Meeting, January 15-16, 2013

Mu3ephase I

phase II

Page 59: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 59 PSI, Open Users Meeting, January 15-16, 2013

BackupBackup

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Andre Schöning, Mu3e Collaboration 60 PSI, Open Users Meeting, January 15-16, 2013

Page 61: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 61 PSI, Open Users Meeting, January 15-16, 2013

Efficiencies and BackgroundsEfficiencies and Backgrounds

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Andre Schöning, Mu3e Collaboration 62 PSI, Open Users Meeting, January 15-16, 2013

Momentum Resolution IMomentum Resolution I

Momentum resolution given by (linearised):

σ p

P∼

ΘMS

Ω

Ω

ΘMS

precision requires large lever arm

(large bending angles Ω)

MS

multiple-scattering angle

B⃗

Page 63: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 63 PSI, Open Users Meeting, January 15-16, 2013

Momentum Resolution IIMomentum Resolution II

Momentum resolution for half turns given by:

σ p

P∼ O(ΘMS

2)

best precision for half turns

design tracking detector for measuring recurlers

Ω∼π

ΘMS

MS

B⃗

Page 64: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 64 PSI, Open Users Meeting, January 15-16, 2013

Multiple Scattering in Silicon

Momentum range p = 15-53 MeV

multiple scattering!

Example: p = 53 MeV/c

MEG: σΘMS= 8 mrad

multiple scatt. per layer X/X0=0.1% → corresponds to 90 μm Silicon

μ → eee: σΘMS= 5 mrad

multiple scatt. per layer X/X0=0.044% → corresponds to 40 μm Silicon

Pixel sensors can be thinned down to 30-50 μm

(examples CMOS MAPS, DEPFET 50 μm)

Page 65: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 65 PSI, Open Users Meeting, January 15-16, 2013

MuPix2 Tests: Double Pulse Resolution

tDP

= 4.7 µs

will improve with MuPix3 chip

Page 66: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 66 PSI, Open Users Meeting, January 15-16, 2013

ToF Readout + New DRS5 Chip

DRS4 chip (PSI) switched capacitor chip

8+1 Channels 700 MS/s- 5 GS/s

New DRS5 chip (PSI) design planned for 2013

≥ 2 MHz continuous hit rate option for Mu3e - ToF readout

Page 67: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 67 PSI, Open Users Meeting, January 15-16, 2013

ToF Readout + STIC Chip

STIC timing chip (KIP Heidelberg) 16 channel ASIC

UMC 180 nm CMOS technology for SiPM readout

tested with MPPC S10362-33-50 SiPM

time resolution 20ps

faster version (STIC II) planned

Page 68: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 68 PSI, Open Users Meeting, January 15-16, 2013

DAQ and Online Filter Farm

pixel detector:

number of (zero suppressed) channels ~275 million

per 50 ns readout frame ~2000 hits

fiber tracker:

number of (zero suppressed) channels about 10k

for muon stop rate of ~2·109 (2·108) muons per second

raw data rate max ~ 250 (25) Gbyte/s (large but smaller than at LHC)

Data Acquisition:

Page 69: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 69 PSI, Open Users Meeting, January 15-16, 2013

DAQ and Online Filter Farm

Online software filter farm

continuous front-end readout (no trigger)

FPGAs and Graphical Processor Units (GPUs)

online track (event) reconstruction

data reduction by factor ~1000

on tape ~ 100 Mbyte/s

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Andre Schöning, Mu3e Collaboration 70 PSI, Open Users Meeting, January 15-16, 2013

Readout Frames

The pixel detector readout is clocked at 20 MHz (50 ns)

Intrinsic time resolution in silicon 10-20 ns (to be experimentally verified)

Precise timing provided by ToF is 0.2-1ns

Decay positrons spread over up to 3 ns (recurler)

Time structure of events in RO frames:

n n+1 n+2n+1 n+3

ToFintrinsic pixel timing

time

Page 71: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 71 PSI, Open Users Meeting, January 15-16, 2013

Magnet

variation of magnetic field

Magnet Design ParameterB

nom = 1 Tesla

Bmax

= 2 Tesla

Length (inner bore) = 2.5mDiameter (inner bore = 1.0 m

Page 72: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 72 PSI, Open Users Meeting, January 15-16, 2013

Magnet: gradient or no gradient?

Homogeneous magnetic field of about 1-1.2 Tesla preferred

MEG

Simulation Results for Baseline Design: 11 hits per electron gradient field

17 hits per electron homogeneous field

Speed of Track Reconstruction: homogeneous field allows for fast

non-iterative analytical calculation

reconstruction speed important for online filtering!

target

curler

homogeneous B-filed

Page 73: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 73 PSI, Open Users Meeting, January 15-16, 2013

Geometrical Acceptance

~ 70% geometrical acceptance dead angle

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Andre Schöning, Mu3e Collaboration 74 PSI, Open Users Meeting, January 15-16, 2013

Detector Acceptance μ+ → e+e+e-

photonpenguin

acc ~ 80%

acc ~ 40%

fourfermion

Minimum electron energy:

4-fermion

T-odd

determines acceptance!

Model Dependence:

measure momenta in range: p=15-53 MeV/c

Page 75: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 75 PSI, Open Users Meeting, January 15-16, 2013

2D versus 3D tracking

cylinder radius 7.5 cm

mu3e decay mu3e decay

cylinder radius 7.5 cm

Page 76: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 76 PSI, Open Users Meeting, January 15-16, 2013

Comparison: μ-Decay Experiments

Sindrum 1988:

σp/p (50 MeV/c) = 5.1%

σp/p (20 MeV/c) = 3.6%

σθ (20 MeV/c) = 28 mrad

VTX: σd= ~ 1mm

X0(MWPC) = 0.08% - 0.17% per layer

MEG 2010 (preliminary):σ

p/p (53 MeV/c) = 0.7 %

σΦ

(53 MeV/c) = 8 mrad

σθ (53 MeV/c) = 8 mrad

VTX: σR=1.4 mm, σ

Z=2.5 mm

Aim for similar or better angular and momentum resolutions, high rates and better vertex resolution ~ 150 μm (combinatorial BG)

Page 77: New Experimental Search for μ→eee · Hisana et al., hep-ph/9510309 Supersymmetric Seesaw Mechanism box diagrams Z-penguin photon. Andre Schöning, Mu3e Collaboration 16 PSI, Open

Andre Schöning, Mu3e Collaboration 77 PSI, Open Users Meeting, January 15-16, 2013

from Calibbi et al. 2012

Comparison of LFV Experiments

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Andre Schöning, Mu3e Collaboration 78 PSI, Open Users Meeting, January 15-16, 2013

Higgs-mediated LFV Yukawa Couplings

Harnik, Kopp, Zupan arXiv:1209.1397