July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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STATUS of the MINOS Experiment

Argonne • Athens • Brookhaven • Caltech • Cambridge • Campinas • Dubna • Fermilab College de France • Harvard • Illinois Inst. of Technology • Indiana • ITEP-Moscow •

Lebedev Livermore • Macalester • Minnesota-Twin Cities • Minnesota-Duluth • Oxford • Pittsburgh Protvino • Rutherford • Sao Paulo • South Carolina • Stanford • Sussex • Texas

A&MTexas-Austin • Tufts • University College London • Western Washington • Wisconsin

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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MINOS

• Main Injector Neutrino Oscillation Search– Precision m2 and sin2(2) measurement

in disappearance

– Beam from Fermilab Main Injector: Mostly tuneable energy

– 2 detectors separated by 735km baseline• Near Detector: 1kt detector at Fermilab

• Far Detector: 5.4kt detector at Soudan

– Improved e limits

– At 735 km, SK m2 1-4 GeV oscillation maximum735 km

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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NuMI Beam• Neutrinos at the Main Injector

– 120 GeV Protons from Fermilab Main Injector

– 10s pulse, every 1.9s

– Proton Intensity:

• 4x1013 protons/pulse design

• 2.5x1013 p/p expected at startup

– Hadrons focused with 2 horns

• Horn and target positionstune beam energy spectrum

Main Injector

Near Detector

470 events/kt-yr

1270 events/kt-yr

2740 events/kt-yr

Decay pipe:678m x 1m radius

Target, Horns

Rock: 240m,muon monitors

Hadron Absorber:4.7 m Al/Fe

103 m

1040 m

Not to scale

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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NuMI Beam Status• Excavation of underground complex

complete

• Decay Pipe installed• Tunnel/Hall Outfitting in progress

• Target has been fabricated

• Horns have been assembled

• Project will be complete/ commissioning starts Dec. 2004 MINOS Near Detector Hall

(100m underground)

Some of the NuMI Shielding -Much more than mass of Near and Far Detectors combined!

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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NuMI Beam Status

Horn 2 Assembly

Decay Pipe

Decay Pipe encased in concrete to protect groundwater

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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Far Detector• 5.4kt total

– 484 planes in two ~14.5m long “super modules”

– Each plane 8m octagon

– 2.54cm Fe, 1cm Scintillator

– ~1.5T Magnetic field

• Readout– 2 ended readout

– 8x optical multiplexing into M16 multi-anode PMTs

– ~92k strips, 23k channels

• Overburden– 710 m (2090 mwe)

1 supermodule Magnet Coil

8m

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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Far Detector Status

Completed MINOS Far Detector

A person

• Far Detector construction completed!– 1st supermodule

operational since 7/02

• Veto Shield– Build from same

scintillator used in detector

– Help ID Atmospheric neutrino interactions

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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Far Detector Data

X

Y

Z

• Up Going Muons: interactions below detector– Use timing to select up

going muons

• Magnetic Field– Distinguish +

Example: 5.4 GeV/c up going

Time vs. Y

Up Going log10(p) distributions MINOS

PRELIMINARY UPGOING MUON DATA

One sign

Other sign

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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Atmospheric Neutrinos• MINOS is 1st Large, Underground

detector with Magnetic Field– Distinguish from +

• vs.

– CPT test: P(P?

Expected number of events:

Number of events in Neutrino Antineutrino 24 kT yearsReconstructed contained 440 260 vertex with muonReconstructed upgoing muon 280 120

For m2=0.003 eV2, sin2 2 = 1.0

2 Probability for nominal neutrino oscillationparameters compared to different values of m2

for antineutrinos.

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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• Same sampling/structure as far detector

• 980 t

• High rate (10s spill)– HE beam: 20 interactions/m/spill– LE beam: 3.2 interactions/m/spill– High speed electronics– 4x multiplexing in spectrometer only

• All Planes have been assembled

Near Detector

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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MINOS Event Topologies identified by in Charged Current interactions

CC NC

e CC

Example Monte Carlo eventsPulse height vs. Strip & plane4-5 GeV neutrinos

MIP energy loss = 30MeV/plane

1 plane 1.4 X0

Interaction length6 planes

1.2m

4.7m

~1.0m

0.7m

1.7m

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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C e

vent

s

Oscillation Measurement• Charged Current events

– Far detector observed/expectation for no oscillations

– Energy dependence yields oscillation parameters

• The Details…– Hadron production

• Unlike Far, Near Detector sees non-point source of neutrinos• MIPP - hadron production experiment at Fermilab

– Neutrino Cross sections– Detector response & Calibration

• 2% relative, 5% absolute• CALDET calibration detector at CERN• See C. Smith’s talk in detector session

Example

No osc.

m2=2x10-3 eV2 sin2(2)=0.9

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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5 Year Plan

• MINOS Collaboration has submitted a 5 year plan to Fermilab Physics Advisory Committee– Physics with beam

starts 2005

– Expect 2.5x1020

protons 1st year

– Request 25x1020

p.o.t total

MC with m2 = 0.0025 eV2, sin2 2 = 1.0

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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Electron Neutrino Appearance

For m2 = 0.0025 eV2, sin2 213= 0.067 For m2 = 0.0025 eV2

Observed number of e CC candidates with and without oscillations.25x1020 protons on target.

3 discovery potential for threedifferent levels of protons on targetand versus systematic uncertaintyon the background.

July 19, 2003 HEP03, Aachen

P. ShanahanMINOS Collaboration

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Summary

• MINOS – Main Injector Neutrino Oscillation Search– 1kt Near Detector at Fermilab, 5.4kt Far Detector at Soudan, MN

• disappearance– Demonstrate oscillatory energy dependence of effect– Precision measurements of m2, sin2(2) (10%)

• e appearance– Improved bounds on |Ue3|2

• Status– Far Detector construction complete– Beam tunnel and Near Detector hall complete

• Installation to start early 2004

• Physics starting April 2005