NuMI Near Hall Detectors: MINOS and Beyond

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NuMI Near Hall Detectors MINOS and Beyond

• Jorge G. Morfín
• Fermilab
• NuFact02
• London, July 2002

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Near Detectors

• Basically could be two types of near detectors
  at neutrino oscillation facilities.
• The most basic is as close to an exact replica of
  the far detector as possible to reduce
  systematics when comparing neutrino beam
  characteristics far-to-near.
• Since this type of near detector must reproduce
  the properties of a mammoth far detector, its
  capabilities to do other types of important
  physics as well as, possibly, detailed
  examination of the neutrino beam are compromised.
• The second type of near detector comes with a
  physics program of its own.
• It can, among many other things, help reduce the
  systematics errors of an oscillation experiment.
• It has the power to better unravel the components
  of the neutrino beam used in oscillation
  experiments.

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MINOS Detectors
Far Detector 5400 tons
Near Detector 980 tons
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MINOS Detectors
Far Detector 5400 tons
Near Detector 980 tons
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Fermilab On-site Beam and Near Detector Hall

• Target-Horn Chase 2 parabolic horns. 50 m
• Decay Region 1m radius decay pipe. 675 m
• Hadron Absorber Steel with Al core 5 m
• Muon range-out dolomite (rock). 240 m
• Near Detector Hall 45 m

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MINOS Near Detector

• Near Detector Hall Length - 45m, Height - 9.6m,
  Width - 9.5m
• Primary objective is to determine the
  characteristics (e.g. the nm energy spectrum) and
  composition of the neutrino beam leaving the
  Fermilab site before oscillations occur.
• These characteristics are then compared with what
  is found at the Far Detector to measure
  oscillation parameters.
• Beam, detector and experimental environment
  should be as similar as possible near/far
• Similarities
• Nature thickness of absorber plates
• Nature granularity of active detector
• Strength of magnetic field
• Differences
• Neutrino Energy Spectra - non-point n source for
  near detector.
• Neutrino Flux is significantly higher at the near
  detector.
• Electronics

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The Near Detector

• Steel scintillator tracking calorimeter
• 282 squashed octagon (3.8 x 4.8m) planes of
  steel - l 16.6m M 0.98 kton
• 153 planes of scintillator
• Sampling every 2.54 cm
• 4cm wide strips of scintillator
• 55/?E for hadrons (Caldet not yet)
• 23/?E for electrons (Caldet yes)
• Forward section 120 planes
• 4/5 partially instrumented
• 1/5 planes full area coverage
• Spectrometer section162 planes
• 4/5 planes not instrumented
• 1/5 planes full area coverage

Beam Center
Coil Hole
Instrumented Region
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MINOS Active Detector
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Near Detector Main Sections
(Muon) Spectrometer Section
Veto Section
Target Section
Hadron Shower Section
60 Planes
40 Planes
20 Planes
160 Planes
Forward Section
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Expected Granularity Hadronic Events in MINOS
(Caldet Data)
Sample Pion Events
Sample Proton Events
3.5 GeV
2 GeV
1 GeV
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New NuMI Near Detector
Beyond MINOS What could/should be assembled? The
second type of Near Detector
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Neutrino Event Energy Distributions and
Statistics

• Reasonably expect 2.5 x 1020 pot per year of NuMI
  running.
• le-configuration Events- Epeak 3.0 GeV, ltEngt
  10.2 GeV, rate 200 K events/ton - year.
• me-configuration Events- Epeak 7.0 GeV, ltEngt
  8.5 GeV, rate 675 K events/ton - year pme
  rate 540 K events/ton - year.
• he-configuration Events- Epeak 12.0 GeV,
  ltEngt 13.5 GeV, rate 1575 K events/ton - year
  phe rate 1210 K events/ton - year.

With E-907 at Fermilab to measure
particle spectra from the NuMI target, expect to
know neutrino flux to 5.
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n-Scattering Physics Topics with NuMI Beam
Energies and Statistics

• Quasi-elastic neutrino scattering and associated
  form-factors.
• Resonance production region (very poorly studied
  up to now).
• The intriguing region where resonance production
  joins deeply inelastic scattering.
• Parton distribution functions (pdf), particularly
  in the high-xBj region.
• Leading exponential contributions of pQCD.
• sin2qW via the ratio of NC / CC as well as ds/dy
  from n-e scattering (check the recent surprising
  NuTeV result).
• Charm physics including the mass of the charm
  quark mc (improved accuracy by an order of
  magnitude, Vcd, s(x) and, independently, s(x.).
• Nuclear effects involving neutrinos. In
  particular are nuclear effects the same for
  valence and sea quarks.
• Strange particle production for Vus,
  flavor-changing neutral currents and measurements
  of hyperon polarization.
• Spin of the strange quark through n elastic
  scattering. Far more accurate with many fewer
  assumptions than charged lepton results for Ds.
• Nuclear physics studies with neutrinos
  (complementary to JLab studies in the same
  kinematic range). Argonne Theory Institute at the
  end of July solely on this topic.

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NuMI Near Hall Dimensions Geometry
Length 45m - Height 9.6m - Width 9.5m
Length Available for New Detector 26 m
Incoming angle n beam 58 mr.
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NuMI Beam Interacts Off-Module-Center
Wonderful - inviting - spot for a new detector
which could use MINOS near detector as a muon
ID/spectrometer!
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A First Significant Step...
Scintillator Strips
MINOS Near
Planes of C, Fe, Pb
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Detector Conceptual Design

• 2m x 2 cm x 2cm scintillator (CH) strips with
  fiber readout.
• Fiducial volume r .8m L 1.5 3 tons of
  scintillator
• Downstream half pure scintillator
• Upstream half scintillator plus 2 cm thick
  planes of C, Fe and W.
• 11 planes C 1.0 ton (Scintillator)
• 3 planes Fe .95 ton (MINOS)
• 2 planes Pb .90 ton
• Readout combination of VLPC and multi-anode
  PMT.
• Use MINOS near detector as muon identifier /
  spectrometer.

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Example of Event Profiles in Scintillator
DetectorDavid Potterveld - ANL
CC En 4.04 GeV, x .43, y .37
CC En 11.51 GeV, x ..34, y .94
Elastic En 3.3 GeV, x .90, y .08
NC En 29.3 GeV, x ..25, y .46
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Scintillator/Fiber RD at Fermilab
Scintillation detector work at Fermilab EM and
hadronic calorimetry Shower max
detectors Pre-shower detectors Photon vetos Fiber
tracker Muon tracking/hodoscopes General purpose
trigger hodoscopes Time-of-Flight
Scintillator Cost lt 5 / kg
Polymer
Dopant
Continuing development of D0 VLPC readout with
750K grant. Produced D0-type arrays for
detailed device analysis at low cost compared to
D0 Goal Demonstrate cost reduction at X10
1 cm transverse segmentation. 1 cm base triangles
yields about 1 mm position resolution for
mips From D0 pre-shower test data
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MINOS Parasitic Running Event Energy Distribution

• MINOS oscillation experiment uses mainly le beam
  with shorter pme and phe runs for control and
  minimization of systematics.
• An example of a running cycle would be
• 12 months le beam
• 3 months pme beam
• 1 month phe beam
• Assuming 2 such cycles (3 year run) with 2.5x1020
  protons/year 860 K events/ton. ltEngt 10.5
  GeV
• DIS (W gt 2 GeV, Q2 gt 1.0 GeV2) 0.36 M events
  / ton.
• Quasi elastic 0.14 M events / ton.
• Resonance Transition 0.36 M events / ton

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Examples Expected Statistical Errors-MINOS
Parasitic
Ratio Fe/C Statistical Errors xBj MINOS
2-cycle .01 - .02 1.3 .02 - .03 1.0
.03 - .04 0.9 .04 - .05
0.8 .05 - .06 0.8 .06 -
.07 0.7
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Prime User he Event Energy Distribution

• Run he beam configuration only! ltEngt 13.5 GeV
• For example, 1 year neutrino plus 2 years
  anti-neutrino would yield 1.6 M n -
  events/ton 0.9 M n - events/ton
• DIS (W gt 2 GeV, Q2 gt 1.0 GeV2) 0.85 M n
  events / ton 0.35 M n events / ton
• Shadowing region (x lt 0.1) 0.3 M events/ton

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Add a Liquid H2/D2Target
Additional Tracking
Solid Scintillator
H_2/D_2
MINOS Near
Additional Tracking
Fiducial volume r 80 cm. and l 150 cm. 350
K CC events LH2 800 K CC events in LD2 per
year he-n running.
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Examples Expected Statistical Errors - he Running
Ratios (he, 1 year n, DIS) Statistical Errors
xBj Fe/ LD2 Fe/C .01 - .02 11 9 .02 -
.03 6 5 .03 - .04 4 3 .04 - .05 3 2 .05 - .06 2
1.7 .06 - .07 1.7 1.4
High xBj (he, 1 year, DIS) Statistical Errors
xBj CH LH2 LD2 .60 - .65 0.6 2 1.4
.65 - .70 0.7 3 1.7 .70 - .75 1.0
4 2 .75 - .80 1.3 5 3 .80 - .85
2 7 5 .85 - .90 3 11 7 .90
- .95 5 17 11 .95 - 1.0 7 25 16
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Detector Event Rates

• Event rates (2.5 x 1020 protons per year)
• Parasitic Running Prime
  User Prime User
• (3 years) (1 year, he-n)
  (2 year, he -n)
• CH 2.60 M 4.80 M 2.70 M
• C 0.85 M 1.60 M 0.90 M
• Fe 0.80 M 1.55 M 0.85 M
• Pb 0.75 M 1.45 M 0.80 M
• LH2 0.35 M 0.20 M
• LD2 0.80 M 0.45 M

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The Ultimate NuMI Neutrino Scattering
FacilityNickolas Solomey
Side Muon ID (Steel Scintillator)
Magnet
Muon ID Steel Scint
TOF
Electromagnetic Calorimeter
Additional Scintillator Tracking
MINOS Near
Scintillator Strips
H_2/D_2
Electromagnetic Calorimeter
Additional Scintillator Tracking
Electromagnetic Calorimeter
Side Muon ID (Steel Scintillator)
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Summary

• Current NuMI/MINOS near detector designed to
  mimic far detector as closely as possible.
• There is a second type of near detector!
• NuMI Beam is Intense
• yielding 860 K events/ton during MINOS run
• yielding 1.6 M events/ton-year in the he-mode.
• NuMI Near Hall
• space for new detector(s) with w(x) 6 m, h(y)
  4 m,(sum) L 25 m.
• NuMI Near Hall Physics can do much of this
  parasitically, need 3 years (n n ) he for full
  potential
• cross section measurements - for own sake,
  oscillation systematics
• spin of strange quark
• strange particle production
• nuclear effects
• PDFs particularly high-x, study of leading
  exponentials of pQCD
• (much improved measurement of ne component of
  beam)
• NuMI Near Hall Detector studies underway
• solid scintillator planes of A 3 - 5 ton
  fiducial volume - cost O(3M)
• liquid H2 / D2 (bubble chamber) large target
  technically feasible - safety requirements.?