A High-Statistics n-Nucleus Scattering Experiment

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New Experiment in the Fermilab Neutrino Program
A High-Statistics n-Nucleus Scattering
Experiment Using an On-Axis, Fine-grained
Detector in the NuMI Beam
MINERnA (Main INjector ExpeRiment
n-A) Received Physics Approval from Fermilab
PAC in April
Jorge G. Morfín - Fermilab
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Both HEP and NP collaborators
Quantitative Study of Low-energy n-Nucleus
Interactions

• D. Drakoulakos, P. Stamoulis, G. Tzanakos, M.
  Zois
• University of Athens, Athens, Greece
• D. Casper
• University of California, Irvine, California
• E. Paschos
• University of Dortmund, Dortmund, Germany
• D. Boehnlein, D. A. Harris, M. Kostin,
• J.G. Morfin, P. Shanahan, P. Spentzouris
• Fermi National Accelerator Laboratory, Batavia,
  Illinois
• M.E. Christy, W. Hinton, C.E .Keppel
• Hampton University, Hampton, Virginia
• R. Burnstein, A. Chakravorty, O. Kamaev, N.
  Solomey
• Illinois Institute of Technology, Chicago,
  Illinois

G. Blazey, M.A.C. Cummings, V. Rykalin Northern
Illinois University, DeKalb, Illinois W.K.
Brooks, A. Bruell, R. Ent, D. Gaskell,, W.
Melnitchouk, S. Wood Jefferson Lab, Newport
News, Virginia S. Boyd, D. Naples, V.
Paolone University of Pittsburgh, Pittsburgh,
Pennsylvania A. Bodek, H. Budd, J. Chvojka,
P. de Babaro, S. Manly, K. McFarland, I.C.
Park, W. Sakumoto, R. Teng University of
Rochester, Rochester, New York R. Gilman, C.
Glasshausser, X. Jiang, G. Kumbartzki, K.
McCormick, R. Ransome Rutgers University, New
Brunswick, New Jersey H. Gallagher, T. Kafka,
W.A. Mann, W. Oliver Tufts University, Medford,
Massachusetts J. Nelson William and Mary
College, Williamsburg, Virginia
Red HEP, Blue NP, Green Theorist
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Motivation Detailed Knowledge of low-energy
Neutrino-Nucleus Interactions DISMALAs we saw
MiniBooNe and K2K improving the situation at
Lower Energies

• Typical samples of NC 1-p production
• ANL
• ? p?? n ? (7 events)
• ? n?? n ?0 (7 events)
• Gargamelle
• ? p?? p ?0 (240 evts)
• ? n?? n ?0 (31 evts)
• K2K and MiniBooNe
• Starting a careful analysis of single ?0
  production.
• Strange Particle Production
• Gargamelle-PS - 15 L events.
• FNAL - 100 events
• ZGS - 7 events
• BNL - 8 events
• Larger NOMAD sample expected

CC
n n m- p
S. Zeller - NuInt04
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The MINERnA Detector
OPTIONAL
C, Fe and Pb Nuclear targets

• Active target of scintillator bars (6t total, 3 -
  5 t fiducial) - M64PMT
• Surrounded by calorimeters
• upstream calorimeters are Pb, Fe targets (1t
  each)
• magnetized side and downstream tracker/calorimeter

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Active Target Module

• Planes of strips are hexagonal
• inner detector active scintillator strip tracker
  rotated by 60º to get stereo U and V views
• Pb washers around outer 15 cm of active target
• outer detector frame, HCAL, spectrometer
• XUXV planes ? module

Inner, fully-activestrip detector
Outer Detectormagnetized sampling calorimeter
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Performance of the DetectorTracking in Active
Target

• Coordinate resolution from triangular geometry is
  excellent
• s 2-3 mm in transverse direction from light
  sharing

3.3cm
1.7cm

• technique pioneered by D0 upgrade pre-shower
  detector

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Location in NuMI Near Hall

• MINERnA preferred running is as close as possible
  to MINOS, (without Muon Ranger), using MINOS as
  high energy muon spectrometer
• If necessary, MINERnA can run stand-alone
  elsewhere in the hall with the muon ranger

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The NuMI Neutrino Beam
Main injector 120 GeV protons
1 km
110 m
Move target only
Move target and Second horn
With E-907(MIPP) at Fermilab to measure particle
spectra from the NuMI target,expect to know
neutrino flux to 3-4 .
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MINERnA will have the statistics to cover a wide
variety of important n physics topics
Assume 9x1020 POT MINOS chooses 7.0x1020 in LE n
beam, 1.2x1020 in sME and 0.8x1020 in sHE
Typical Fiducial Volume 3-5 tons CH, 0.6 ton
C, 1 ton Fe and 1 ton Pb 3 - 4.5 M events
in CH 0.5 M events in C 1 M events in Fe 1 M
events in Pb
nm Event Rates per fiducial ton Process CC
NC Quasi-elastic 103 K 42 K Resonance 196 K
70 K Transition 210 K 65 K DIS 420
K 125 K Coherent 8.4 K 4.2 K TOTAL 940 K 305 K

• Main Physics Topics with Expected Produced
  Statistics
• Quasi-elastic 300 K events off 3 tons CH
• Resonance Production 600 K total, 450 K 1p
• Coherent Pion Production 25 K CC / 12.5 K NC
• Nuclear Effects C0.6M, Fe 1M and Pb 1 M
• sT and Structure Functions 2.8 M total /1.2 M
  DIS event
• Strange and Charm Particle Production gt 60 K
  fully reconstructed events
• Generalized Parton Distributions (few K
  events?)

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To perform a wide variety of n physics
studiesWhat is the MINERnA Physics Program?

• Physics Monte Carlos - NEUGEN (H. Gallagher) and
  NUANCE (D. Casper)
• Quasi-elastic (n n --gt m- p, 300 K events off
  3 tons CH) - A. Bodek, H. Budd
• Precision measurement of s(En) and ds/dQ
  important for neutrino oscillation studies.
• Precision determination of axial vector form
  factor (FA), particularly at high Q2
• Study of proton intra-nuclear scattering and
  their A-dependence (C, Fe and Pb targets)
• Resonance Production (e.g. n N --gtn /m- D,
  600 K total, 450K 1p) - S.Wood, M.Paschos
• Precision measurement of s and ds/dQ for
  individual channels
• Detailed comparison with dynamic models,
  comparison of electro- photo production, the
  resonance-DIS transition region -- duality
• Study of nuclear effects and their A-dependence
  e.g. 1 p lt-- gt 2 p lt--gt 3 p final states
• Coherent Pion Production (n A --gt n /m- A
  p, 25 K CC / 12.5 K NC) - H. Gallagher
• Precision measurement of s(E) for NC and CC
  channels
• Measurement of A-dependence
• Comparison with theoretical models

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To perform a wide variety ofn physics studies -
continued

• Nuclear Effects (C, Fe and Pb targets)- S. Boyd,
  R. Ransome and J. G. M.
• Final-state intra-nuclear interactions. Measure
  multiplicities and Evis off C, Fe and Pb.
• Measure NC/CC as a function of EH off C, Fe and
  Pb.
• Measure shadowing, anti-shadowing and EMC-effect
  as well as flavor-dependent nuclear effects and
  extract nuclear parton distributions.
• MINERnA and Oscillation Physics - D. A. Harris
• MINERnA measurements enable greater precision in
  measure of Dm, sin2q23 in MINOS
• MINERnA measurements important for q13 in MINOS
  and off-axis experiments
• MINERnA measurements as foundation for
  measurement of possible CP and CPT violations in
  the n-sector
• sT and Structure Functions (2.8 M total /1.2 M
  DIS events) - C. Keppel and J. G. M.
• Precision measurement of low-energy total and
  partial cross-sections
• Understand resonance-DIS transition region -
  duality studies with neutrinos
• Detailed study of high-xBj region extract pdfs
  and leading exponentials over 1.2M DIS events
  

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To perform a wide variety ofn physics studies -
continued

• Strange and Charm Particle Production (gt 60 K
  fully reconstructed exclusive events) -
  A. Mann, V. Paolone and N. Solomey
• Exclusive channel s(En) precision measurements -
  importance for nucleon decay background studies.
• Statistics sufficient to reignite theorists
  attempt for a predictive phenomenology
• Exclusive charm production channels at charm
  threshold to constrain mc
• Generalized Parton Distributions (few K events??)
  - W. Melnitchouk and R. Ransome
• Provide unique combinations of GPDs, not
  accessible in electron scattering (e.g. C-odd, or
  valence-only GPDs), to map out a precise
  3-dimensional image of the nucleon. MINERnA would
  expect a few K signature events in 4 years.
• Provide better constraints on nucleon (nuclear)
  GPDs, leading to a more definitive determination
  of the orbital angular momentum carried by quarks
  and gluons in the nucleon (nucleus)
• provide constraints on axial form factors,
  including transition nucleon --gt N form
  factors

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A few MINERnA Physics ResultsQuasi-elastic
ScatteringMINERnA 300 K events off CH and over
100 K off of Fe and Pb

• Cross-section important for understanding
  low-energy neutrino oscillation results and
  needed for all low energy neutrino monte carlos
  used in neutrino oscillation analyses.
• Constrained kinematics help measure final state
  interactions off three different nuclear targets.

S. Zeller - NuInt04
MINERnA
Expected MiniBooNe And K2K measurements
Expected MiniBooNe and K2K measurements
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Extraction of FA with Selected Sample
Expected MiniBooNe and K2K measurements
MINERnA will have the statistics and Q2 range to
distinguish between the two different suggested
Q2 behaviors.
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Coherent Pion Production

• Characterized by a small energy transfer to the
  nucleus, forward going p. NC (p0 production)
  significant background for nm --gt .ne oscillation
  search
• Data has not been precise enough to discriminate
  between several very different models.
• Expect roughly (30-40) detection efficiency with
  MINERnA.
• Can also study A-dependence with MINERnA

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Coherent Pion Production MINERnA 25 K CC / 13
K NC CH and 25 K (50K) CC / 13 K (25K)NC Fe
(Pb)H. Gallagher
Selection criteria reduce the signal by a factor
of three - while reducing the background by a
factor of 1000. Resulting sample is
5 K CC coherent events
signal
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Coherent Pion Production MINERnA 25 K CC / 12.5
K NC events off C - 8.3 K CC/ 4.2 K NC off Fe and
Pb
Rein-Seghal
Paschos- Kartavtsev
MINERnA
Expected MiniBooNe and K2K measurements
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Physics with the Resonance ( Transition Region)
Scattering Sample gt 1,000,000 events (400 K 1p)
produced
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Resonance Production - DS. Wood and M. Paschos
Total Cross-section and ds/dQ2 for the D
assuming 50 detection efficiency Errors are
statistical only 175K D DO NOT FORGET
RADIATIVE DECAYS AS BACKGROUND TO nm --gt ne
sT
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Resonance Production - Nuclear Effects
Adler, Nusinov, Paschos model (1974)
One obvious omission, this model does not
include hadron formation length corrections
En 5 GeV
p
LH on
p
p-
LH off
NEUGEN
MINERnA can measure LH off of C, Fe and Pb
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Nuclear Effects MINERnA 2.8 M events off CH,
600 K off C and 1 M events off of Fe and PbS.
Boyd, JGM, R. Ransome
Q2 distribution for SciBar detector
Problem has existed for over two years
All known nuclear effects taken into
account Pauli suppression, Fermi Motion, Final
State Interactions They have not
included low-n shadowing that is only
allowed with axial-vector (Boris Kopeliovich at
NuInt04) Lc 2n / (mp2 Q2) RA (not mA2)
Lc 100 times shorter with mp allowing low n-low
Q2 shadowing ONLY MEASURABLE VIA NEUTRINO -
NUCLEUS INTERACTIONS! MINERnA WILL MEASURE
THIS ACROSS A WIDE n AND Q2 RANGE WITH C
Fe Pb
Larger than expected rollover at low Q2
MiniBooNE From J. Raaf (NOON04)
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Nuclear Effects

• Modified Interaction Probabilities
• Shadowing Region (xBj lt 0.1) Expect a difference
  in comparison to e/m - nucleus results due to
  axial-vector current and quark-flavor dependent
  nuclear effects.
• EMC-effect (0.2 lt xBj lt 0.7) depends on
  explanation of the effect
• Fermi Motion Effect (xBj gt 0.7) should be the
  same as e-nucleus scattering
• With sufficient n measure flavor dependent
  effects.
• NC/CC off C, Fe and Pb
• Over 100 K CC and 30 K NC with EH gt 5 GeV on Fe
  and Pb, times 3 for Carbon.

S. Kulagin prediction for shadowing region
xBj
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Example MINERnA Sensitivity to Nuclear Effects

• Use NEUGEN Monte Carlo model to study
• intranuclear scattering and absorption
• D. Harris

EHad (3s) - EHad (-3s) / EHad (-3s)
Fe
Study effects of p absorption
Study p rescattering as f(A)
Pb
Errors from low MC statistics
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Multiplicity and Containment
RES
QE
DIS
All
Average multiplicity (no neutrons) as a function
of EH
Fraction of events fully contained within active
volume downstream of nuclear targets as a
function of EH
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Strange and Charm Particle Production
Existing Strange Particle Production Gargamelle-PS
- 15 L events. FNAL - 100 events ZGS - 7
events BNL - 8 events Larger NOMAD
inclusive sample expected

• Theory Initial attempts at a predictive
  phenomenology stalled in the 70s due to lack of
  constraining data.
• MINERvA will focus on exclusive channel strange
  particle production - fully reconstructed events
  (small fraction of total events) but still .
• Important for background calculations of nucleon
  decay experiments
• With extended n running could study single
  hyperon production to greatly extend form factor
  analyses
• New measurements of charm production near
  threshold which will improve the determination of
  the charm-quark effective mass.

MINERnA Exclusive States 100x earlier samples 3
tons and 4 years DS 0 m- K L0 10.5 K m- p0
K L0 9.5 K m- p K0 L0 6.5 K m- K- K
p 5.0 K m- K0 K p0 p 1.5 K DS 1 m-
K p 16.0 K m- K0 p 2.5 K m- p K0n 2.0
K DS 0 - Neutral Current n K L0 3.5 K n K0
L0 1.0 K n K0 L0 3.0 K
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Challenges of Oscillation Measurements

• MINOS measurement of Dm2
• need a wide band beam to do this
• need to understand the relationship between the
  incoming neutrino energy and the visible energy
  in the detector
• NOnA/T2K search for nm? ne
• Must have accurate prediction for backgrounds
• Once a signal is seen, its extracting a
  probability
• NOnA/T2K precision measurement of sin2 2q23
• Have to predict NC background

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How Nuclear Effects enter MINOS Dm2 Measurement

• Measurement of Dm2 with MINOS
• Need to understand the relationship between the
  incoming neutrino energy and the visible energy
  in the detector
• Expected from MINERnA
• Improve understanding of pion and nucleon
  absorption
• Understand intra-nuclear scattering effects
• Understand how to extrapolate these effects from
  one A to another
• Improve measurement of pion production
  cross-sections
• Understand low-n shadowing with neutrinos

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How MINERnA Would Help NOnA/T2K Once a Signal
is seen
Total fractional error in the predictions as a
function of Near Detector off-axis Angle
Current Accuracy of Loe-energy Cross-sections DQE
20 DRES 40 DDIS 20 DCOH 100
With MINERnA Measurements of s DQE 5 DRES 5,
10 (CC, NC) DDIS 5 DCOH 20
Without MINERnA measurements of s, oscillation
probability measurement could be limited by
systematics!
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How MINERnA Helps NonA/T2KBackground Predictions
Total fractional error in the background
predictions as a function of Near Detector
off-axis Angle
Current Accuracy of Cross-sections DQE 20 DRES
40 DDIS 20 DCOH 100
With MINERnA Measurements of s DQE 5 DRES 5,
10 (CC, NC) DDIS 5 DCOH 20
With MINERnA measurements of s, decrease
fractional error on background prediction again
by a factor of FOUR
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Detector Cost Summary and ScheduleBeam and
Experimental Hall already Exist!

• Costs are primarily scaled from experience of
  MINERnA collaborators on CMS HCAL and MINOS
• 2.55Mequipment
• 1.41Mlabor, EDIA
• 1.54Mcontingency(39 avg.)
• Sum 5.5M
• Full project costs not updated since proposal
  (steel costs up)
• Schedule for full detector 26 - 30 months from
  start

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Summary

• MINERnA, a recently approved experiment, brings
  together the expertise of the HEP and NP
  communities to address the challenges of
  low-energy n-A physics.
• MINERnA will accumulate significantly more events
  in important exclusive channels across a wider En
  range than currently available. With excellent
  knowledge of the beam, s will be well-measured.
  
• With C, Fe and Pb targets MINERnA will enable a
  systematic study of nuclear effects in n-A
  interactions, known to be different than
  well-studied e-A channels.
• WE NEED A LARGE ANTINEUTRINO EXPOSURE
• We welcome additional collaborators!!

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Increased n statistics (factor 10) will NOT
significantly improve results at the end of the
experiment - systematics dominate result

• MnBNe K2K MNRvA T2K-I
• Quasi-elastic
• Resonance Production - 1pi
• Resonance Production - multi-pi
• DIS
• Coherent Pion Production
• Strange and Charm Particle Production
• Nuclear Effects
• sT and Structure Functions
• s(x) and c(x)
• High-x parton distribution functions
• Spin-dependent pdfs
• Generalized Parton Distributions