Presentation to HEPAP R. Plunkett 12 October, 2006

The NuMI/MINOS Experimental Program Status and Ongoing Prospects

Robert Plunkett Fermi National Accelerator Laboratory Batavia, IL, USA

Presentation to HEPAP 12 October 2006 Presentation to HEPAP ν R. Plunkett Neutrino physics with µ beams 12 October, 2006

Studies of oscillations of µ ν →ντ at atmospheric scale θ 4 2 2 ν µ = θ ∆ P →ντ cos 13 sin 2 23 sin ( 13)

Search for and utilize 2 ν µ →ν ∆ = ∆ at atmospheric scale e 13 1.27 m13 L/ Eν

θ ∆2 ν 2 2 13 2 P →ν = sin sin 2θ sin (∆ aL) µ e 23 13 ∆ 2 13 m ( 13 m aL) Presentation to HEPAP R. Plunkett MINOS Long-Baseline Experiment 12 October, 2006

Study the νµ→ντ oscillation hypothesis, by ∆ 2 2 θ measuring precisely | m 32| and sin 2 23 ν ν Search for µ→ e oscillations Constrain contributions of exotic phenomena e.g Sterile ν or ν decay Compare ν, ⎯ν oscillations Test of CPT violation Atmospheric neutrino oscillations Phys. Rev. D73, 072002 (2006) Far Detector: 5400 tons Near Detector: 980 tons Detector 2 2 Detector 1 735 km Presentation to HEPAP NuMI Neutrino Beam R. Plunkett 12 October, 2006

Horn and Stripline 207m

•120 GeV protons strike the graphite target • Nominal Intensity 2.4x1013 ppp with ~2 sec cycle time. • Initial intensity ~2.5 x 1020 protons/year • Ultimate intensity ~ 3.2 x 1020 protons/year (2008-9) Presentation to HEPAP R. Plunkett Performance of NuMI 12 October, 2006 DOE FY06 performance Excellent turn on and measure commissioning. FYO5 exceeded Fermilab Tritium expectations. Mitigation Horn water leak, replace Beamline components target have caused unscheduled Water system downtime in FY06 Horn ground problem fault repair Totals: FY05 ~6.8 x 1020 FY06 >1.0 x 1020 Presentation to HEPAP Recent Performance of Main R. Plunkett Injector for NuMI (10/2/06) 12 October, 2006

Protons per Beam Power extraction

1012 Protons Kilowatts Presentation to HEPAP The MINOS Detectors R. Plunkett 12 October, 2006

NEAR FAR 0.98 Kton 5.4 Kton

MINOS Detector Hall, Fermilab Soudan Underground Lab, Minnesota Both detectors are tracking calorimeters composed of interleaved planes of steel and scintillator – uptimes routinely exceed 95-97%. - 2.54 cm thick steel planes -4.1 cm wide scintillator strips - 1.5 T toroidal magnetic field. - Multi-Anode Hamamatsu PMTs (M16 Far & M64 Near) - Near electronics optimized for high occupancy (~20) during 10 µs spill - Energy resolution: 55%/√E for hadrons, 23%/√E for electrons - Muon momentum resolution ~ 6 % from range ( ~ 12 % from curvature ) Presentation to HEPAP Large event rate in near detector R. Plunkett 12 October, 2006

A spill (10 µs) in near detector

Individual Events Beam arrives in 10 µs batches

Multiple events separated by timing, topology.

Relative timing greatly simplifies event identification at far detector Presentation to HEPAP R. Plunkett Near Detector Distributions 12 October, 2006

Track Angle (wrt vert.) Mean 92.76 • Acceptance well RMS 15.75 reproduced by ND Mean 92.80 simulation RMS 15.55 • Track angle w.r.t. vertical exhibits characteristic -3o to Sneak Preview – Soudan Far Detector CC events going upward X Vertex Z Vertex ND ND ND Presentation to HEPAP R. Plunkett Minos Far Detector Events 12 October, 2006

Contained CC event Expected rate ~3/day

Far Detector triggers on spill time (50 µs window), also activity triggers

Further require fiducial, angle cuts

Estimate ~9% NC background, <1 cosmic event Selection of FD events and Presentation to HEPAP R. Plunkett prediction of Spectrum 12 October, 2006

Event Classification Parameter POT

16 MINOS 1.27×1020 POT No oscillations

Best fit

Events/GeV/10 5 10 15 NearReconstructed Detector Spectrum Eν (GeV) Likelihood based on event vs. default MC (blue) and length, pulse height in track tuned MC (red) pHE/200kA Use near detector data, beam kinematics to predict far spectrum

Also use bin-to-bin ratios, direct fitting to simulation, results stable. Presentation to HEPAP R. Plunkett MINOS Best-Fit Spectrum 12 October, 2006

FD neutrino spectrum and ratios

MINOS MINOS NC Subtracted ∆ 2 = +0.44 + × −3 2 m32 2.74−0.26 (stat syst) 10 eV 2 θ = + sin 2 23 1.00−0.13 (stat syst)

Expected FD Data/MC Data Sample (Matrix Method; Data (Matrix Method) Unoscillated) FD Event totals νµ (<30 GeV) 215 336.0±14.4 0.64±0.05

νµ (<10 GeV) 122 238.7±10.7 0.51±0.05

νµ (<5 GeV) 76 168.4±8.8 0.45±0.06 Presentation to HEPAP R. Plunkett Allowed Region 12 October, 2006

• Fit includes penalty terms for three main systematic uncertainties – Near/Far Normalization – Hadronic E scale – NC contamination

• Fit is constrained to physical region: 2 θ sin (2 23)≤1

∆ 2 = +0.44 × −3 2 m 32 2.74 −0.26 10 eV 2 θ = sin 2 23 1.00 −0.13 Presentation to HEPAP Fermilab Proton Plan for R. Plunkett NuMI Beamline 12 October, 2006 Currently, 5 booster batches for NuMI is main running mode Expansion of “slip-stacking” scheme will allow 9 batch running. Move from current values to ~400 kW. Within booster capability Expect Main Injector collimators (control losses) and some RF changes required for high intensities Slip-stacking graphically Proton plan has realistic shutdowns, First batches blue efficiencies, turn-on curves. Second batches purple Presentation to HEPAP Proton Plan Expectation for R. Plunkett NuMI Beam 12 October, 2006 16 NuMI Totals 1.40E+21 Base (2005 Review) Design (2005 Review) 1.20E+21 Base (from 8-1-06) Design (from 8-1-06) 1.00E+21 These values used by MINOS to 8.00E+20 7.5 compute sensitivities Protons 6.00E+20

4.00E+20 2.5

2.00E+20

Actual value as of 8/1/06 0.00E+00 1/1/2005 1/1/2006 1/1/2007 1/1/2008 1/1/2009 Date Presentation to HEPAP R. Plunkett Projected MINOS Sensitivity 12 October, 2006

νµ Disappearance • MINOS sensitivity for different POT MC MINOS MC • Current best values used as input: ∆ 2 -3 2 m 32=2.74x10 eV 2 sin 2θ23=1.00 • Contours are 90% C.L. statistical errors only Presentation to HEPAP R. Plunkett Potential for Electron Identification 12 October, 2006 Challenging because of detector granularity – typical electron is 8 planes long, 4 strips wide. Background high – especially misidentified NC. Several algorithms under study

2θ sin2( 13) = 0.1

Beam direction

ν ν beam ν ν osc µ CC NC e τ CC Total e 5.6 39.0 8.7 4.7 58.0 29.1 Background composition from MC (16 x 1020 POT) 8.7 GeV electron candidate from data Presentation to HEPAP R. Plunkett Exclusion and Discovery Potential 12 October, 2006

Result presented as function of mass hierarchy, CP-violating phase δ. e.g mass hierarchy ±30% effect on rate. MINOS can improve significantly on CHOOZ limit. Full program of running with proton plan strengthens MINOS capabilities.

4 x 1020 POT 16 x 1020 POT Presentation to HEPAP R. Plunkett Conclusions and Expectations 12 October, 2006 • The MINOS experiment and NuMI beam have had a successful first running period. – Two publications accepted, atmospheric and beam oscillation papers – 3 more in pipeline. • Operational difficulties with the NuMI beam have been repaired – Tritium mitigation, horn and target problems – Remarkable effort by Fermilab Accelerator Division – “Industrialization” effort for spares underway • MINOS has active short and long-term physics program – Short term includes improved CC analysis, first ND physics, special topics. • Fermilab proton plan provides a well-defined path forward in proton Intensity • MINOS program has developed a robust scientific culture – Strong involvement by all segments of the collaboration in the CC PRL – Commitment to young people in positions of importance (32 postdocs, ~40 students)