Particle Production in the MICE Beam Line

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Particle Production in the MICE Beam Line

Jean-Sebastien Graulich, University of Geneva

MICE Beam Line and Instrumentation

Experimental Method Proton and Pion Content

The R&D Effort Towards Neutrino Factory The Muon Ionization Cooling Experiment

ISIS

MICE Hall R5.2

What is a Neutrino Factory A neutrino factory is based on high energy muon storage ring.It provides high energy electron- and muon-neutrinos in equal quantities.Ideal for the study of the “Golden” oscillation channel:e , e and e , e

Neutrino Factory physicsAssociated with the proper neutrino detector (several thousand km away) a Neutrino Factory would offer a uniqueopportunity to study neutrino mass hierarchy, leptonic CP violation and neutrino mixing unitarity.

PrerequisiteCooling (or emittance reduction) of a tertiary muon beam prior to acceleration.Major uncertainty on the cost and feasibility. It is made difficult by the short lifetime (2.2 s) of the muon.

Electron and Muon Content

Simulations ReferencesConclusion

We have measured relative proton and pion rates in the MICE beam line at ~321MeV/c, 374 and 414 MeV/c. Asexpected, proton production drops drastically when decreasing momentum and has all but disappeared at ~321 MeV/c.With this particular layout of detectors, a good setting was established at ~321 MeV/c for producing a pure positivepion beam for further studies.

TOF1& cage

Tracker Solenoid 1

Tracker 1

PhotonMuon

Electron

Focus coilRF

H2 absorber

a full implementation of MICE with GEANT4 (G4MICE) (below an example)allows simulation and reconstruction of all steps of MICE. There is also a simpler ICOOL implementation of MICE for optimization The beam line also has a G4beamline description and Turtle for optimizations

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B2 Scan at 414 MeV/c

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The experiment is located at STFC Rutherford Appleton Lab (UK)

1) Turn downstream Quadrupoles OFF2) Start with 480 MeV/c proton momentum at B1.3) Tune Q1, Q2 and Q3 maximize rate in GVA24) Scan dipole magnet B2 at various proton momentums :

414 MeV/c, 374 MeV/c, 322 MeV/c,and measure Pion and Proton rates

The Time of flight technique is used to identify particles

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Time of flight GVA1-GVA2 (ns)Time of flight GVA1-GVA2 (ns)

Time of flight GVA1-GVA2 (ns)Time of flight GVA1-GVA2 (ns)

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Starting from a 300 MeV/c pion beam, we reduced gradually the field until the momentum selected corresponds to 100 MeV/c.At this momentum only positrons can travel through the beam line.

Starting from a 300 MeV/c pion beam, we reduced gradually the field until the momentum selected corresponds to 100 MeV/c.At this momentum only positrons can travel through the beam line.

Starting from a 300 MeV/c pion beam, we reduced gradually the field until the momentum selected corresponds to 100 MeV/c.At this momentum only positrons can travel through the beam line.

Aerogel Cherenkov Counters• upstream pion/muon/electron separation• 2 containers of aerogel radiator with different indices of refraction (n = 1.07, 1.12)• ~5 p.e. in each PMT for beta=1

Time of Flight Stations• Hodoscopes using fast scintillator bars, read by PMTs atboth ends, arranged in 2 planes (X and Y for betterperformances)

MICE is set up to build a section of ionization cooling, placeit in a muon beam and test it in a variety of beam and optics configurations. An affordable section of cooling providing 10% reduction of transverse emittance is placed in a muon beam of 140 - 240 MeV/c. By measuring the particles one by one the emittance can be determined before and after the cooling channel with a precision of one part per mil.