Opportunities for Experiments Based onStored Muon Beams at Fermilab

Milorad PopovicJean-Francois Ostiguy

FermilabAugust, 2014

Motivation• Measure neutrino cross-section with better than 10%

precision • Take advantage of the existing accelerator complex

configuration providing beam to the New Muon g-2 Experiment

• Utilize existing detectors (MicroBooNE, ICARUS)• Minimize initial investment. Providing a suitable building to

house the detector would be the only investment required • Describe possible improvements in collecting and storing

muons that would allow cross-section measurements with a precision of a few percent with a modest additional investment.

• Provide a suitable test facility for future NF

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The Context

• We revisit the idea of using the Debuncher as a storage ring for muons

• the g-2 Experiment expects 6x10-6 stored muons per 8 GeV proton on target

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g-2 Experiment• Booster pulse(5x1012 Protons@ 8 GeV) is separated in 4

bunches (~100 ns long) in the Recycler• The Booster is a 15 Hz machine (not all cycles are used)• Target Station is AP0 (Antiproton production target station)

and was run with beam power up to 72 kW ( 120 GeV beam from Main Injector)

• 3.1 GeV/c Pions/Muons are collected using Lithium Lens ( this lens was used for collection of 8.9 GeV/c Antiprotons with ~0.5 Hz)

• Debuncher is used as delay line for muons (beam is stored for 3 turns).

• Muons go to g-2 storage ring for experiment.

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5

Concept: g-2 Experiment 6x10-6 stored muons in the Debuncher per 8 GeV proton on target

Booster/Linac

Extraction from RR

Injection to RR

NEW TRANSFER LINE

A3 lineA2 line

Main Injector

F0P1 line

MI-52

MI-30

p

Recycler

_p

MI-10

Pbar

AP0

P2 line

Accelerator Overview

INJ8GeV

6

Muon Campus = Mu2e + g-2 + ??? Muon Campus = Mu2e + g-2 + ???

Mu2e

g-2

G4BeamLine simulations of g-2

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• In simulation 1.4x1010 protons on AP0 target

after Li lens

at end of transfer line

after one turn Debuncher

g-2 simulations

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6x10-6 stored muons in the Debuncher per one 8 GeV proton on target

after Li lens

at the endof transfer line

after one turn in Debuncher

Proton Beam Like for g-2,but with g-2 off

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• 5x1012 protons in a Booster pulse• 3 Hz, 8 GeV Booster• Muons are stored for ~100 turns• Running time 107 Sec (1 year)• 100 ton detector, 10 meters downstream from ring

~ 400 CC neutrino events

This is for about the cost of moving an existing detector (BooNE??, 60T) and building a new detector housing (about 3M$)

Looking in the near future ( cost~$0.0)

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• 1x1013 protons from MI (two Booster pulses slip stacked)• 1 Hz, 120 GeV MI• Muons are stored for ~100 turns• Running time 107 Sec• 100 ton detector, 10 meters downstream from ring

~ 5x400 CC neutrino events

Looking Into the Future ( cost~$??)

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• 1x1013 protons from MI (two Booster pulses, slip stacked)• 1 Hz, 120 GeV MI• New Li lens r = 2 cm to increase collection of pi’s ( x1.5) • Make ring to be racetrack (x 1.5)• Running time 107 Sec• Larger detector, ~500 ton detector( x5)

~ 1.5x1.5x5x5x400 CC neutrino events

Questions ?

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The End

Questions ?

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SBN Program

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Experimental CC Inclusive Cross Section Data

Reference: PDG Handbook (2013)

G-2 simulations• Hi Milorad,

• Please find attached the momentum distributions of pions and muons at three different locations in the g-2 beamline:

• START - after the Li lens • VD5 - at injection into the Debuncher Ring• STOP - after one revolution around the Debuncher Ring.

• For normalization, the number of incident 8-GeV-energy protons in this simulations was 1.47e10.• The simulations were conducted using the so-called "default" parameters of the proton beam spot

size on the target (sigma_x=sigma_y=0.5 mm) and the Li-lens. With an additional optimization of the proton beam parameters (reducing the spot size on the pion production target) and optimization of the Li-lens position relative to the target at given field strength, the yield of the muons can be increased by may be additional ... 30%(?) -- I don't have a precise number for this.

• The "magic momentum" is 3.094 GeV/c.

• Hopefully this helps. If you have any questions, please don't hesitate to contact me.

• Best regards,• Volodya

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