Accelerator Based Neutrino Physics at Fermilab

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Accelerator Based Neutrino Physics at Fermilab

• E. Craig Dukes
• University of Virginia
• 31 October 2008
• SESAPS 2008

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It has been a Decade Since Neutrino Physics
Really Got Interesting
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A Huge Amount has been Learned in the Past Decade
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What Remains to be Learned?

• What is the value of ?13, the mixing angle
  between first- and third-generation neutrinos
• Impacts mass hierarchy measurement
• Impacts CP-violation search
• Is the mass hierarchy normal or inverted?
• Is ?23 maximal (45 degrees)? if so, why?
• Are neutrinos and anti-neutrinos different?
• Do neutrinos respect CP? If not, is CP violation
  in the neutrino sector responsible for the
  matter-antimatter asymmetry in the universe?

I will focus only on what Fermilab is doing to
address these questions, with apologies to those
involved in the efforts outside of Fermilab
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The Past
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Fermilab has long history of n physics

• Last fixed target run (1997) two neutrino
  experiments DONUT and NuTeV
• DONUT nt discovery
• NuTeV sin2qW anomaly

DONUT
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The Present
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Fermilab has built two new Neutrino Beams

• 120 GeV protons from Main Injector
• Beam
• 4 x 1013 p/1.87 s (0.4 MW)
• Experiments
• MINOS (running)
• MINERvA (construction)
• NOvA (beginning construction)
• ArgoNeuT (being installed)
• LAr5 at SOUDAN (planning)

• 8 GeV protons from Booster
• Beam
• 4 x 1012 p/0.20 s
• Experiments
• MiniBooNE (running)
• SciBooNE (just completed)
• MicroBooNE (approved)

NUMI Beamline
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MiniBooNE
Appearance Experiment nm?ne (nm?ne)
Running on anti-nms until April 2008
Rule out LSND result
Find low-energy excess
LSND Result
Designed to confirm or refute the LSND
oscillation result
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Do We Know the Low Energy sn?

• M.C. Martinez et al., arXiv0805.2344 nucl-th
  (2008) - K.S. Kim, L.E. Wright,
  nucl-th/0705.0049 (2007)
• - O. Benhar, AIP Conf. Proc. 967, 111 (2007)
  - A. Butkevich, S.
  Kulagin, nucl-th/0705.1051 (2007)
• A.V. Butkevich, arXiv0804.4102 nucl-th (2008)
  - J.E. Amaro et al., PRC 75,
  034613 (2007)
• M.J. Vincente Vacas et al., arXiv802.1128
  nucl-th (2008) - A. Bodek et al.,
  arXiv 0708.1827 hep-ex (2007)
• A. Bodek et al., Eur. Phys. J. C53, 349 (2008)
  - P. Lava et al., PRC
  73, 064605 (2006)
• A.M. Ankowski et al., AIP Conf. Proc. 967, 106
  (2007) - O. Benhar et al.,
  nucl-ex/0603029 (2006)
• A.V. Butkevich, S.A. Kulagin, arXiv0711.3223
  nucl-th (2007) - R. Bradford et al.,
  hep-ex/0602017 (2006)
• J.E. Amaro et al., arXiv0710.5884 nucl-th
  (2007) - K.S. Kuzmin et al., Acta
  Phys. Polon. B37, 2337 (2006)
• A.N. Anatov et al., Phys. Rev. C75, 064617
  (2007) - J. Nieves et al., Phys.
  Rev. C73, 025504 (2006)
• T.W. Donnelly, Eur. Phys. J. A21, 409 (2007)
  - M.C. Martinez et al., PRC 73,
  024607 (2006)
• T. Nasu et al., AIP Conf. Proc. 967, 187 (2007)
  - A. Meucci et al., Acta
  Phys. Polon, B27, 2279 (2006)
• N. Jacjowicz et al., AIP Conf. Proc. 967, 292
  (2007) - C. Giusti et al.,
  nucl-th/0607037 (2006)
• K.S. Kim et al., J. Phys. G34, 2643 (2007)
  - N. Jachowicz et al., NP. Proc.
  Suppl. 155, 260 (2006)
• J.A. Caballero et al., nucl-th/0705.1429 (2007)
  - G. Co,
  ActaPhys.Polon.B37, 2235 (2006)
• M. Martini et al., Phys. Rev. C75, 034604
  (2007) - M. Valverde et al.,
  Phys. Lett. B642, 218 (2006
• E. Hernandez et al., Phys. Lett. B647, 452
  (2007) - M. Valverde et
  al., Phys. Lett. B638, 325 (2006)
• A. Bodek et al., arXiv 0709.3538 hep-ex
  (2007)
• M.V. Ivanov et al., Phys. Rev. C77, 034612
  (2008) - H. Nakamura et al.,
  hep-ph/0705.3884 (2007)

New sn calculations 2006-2008 (Sam Zeller)
QE
Single p production
DIS
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Beware neutrino anomalies can be important!
Beta-decay anomaly
J. Chadwick, Verh. d. Deutsch. Phys. Ges. 16,
383, 1914.
Solar neutrino anomaly
Atmospheric nm/ne anomaly in proton decay
experiments
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MINOS (Main Injector Neutrino Oscillation Search)

• Detector
• NUMI beam
• Long baseline 735 km
• 5.4 kt far detector, 1kt near
• Optimized for nm disappearance
• Sampling 2.54 cm Fe / 1.0 cm scint.
• Magnetic field sign of charge

• Goals
• Make precision measurements of Dm232 and sin22q23
• Confirm oscillations vs decay/decoherence

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MINOS Results

• Dm232 (2.43 0.13) x 10-3 eV2 (68 CL)
• sin2(2q23) gt 0.90 (90 CL)
• Decoherence disfavored at 5.7s
• Decay disfavored at 3.7s

5 error!
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MINOS Future
MINOS Plans

• Will run through 2010 10x1020 pot
• Want to continue running ns beyond 2011
• Want to run anti-ns as well

Projected sin2(2q13) Sensitivity
At CHOOZ limit expect 12 ne signal events and 42
background events with 3.25x1020 protons.
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The Immediate Future
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MINERnA Physics Goals

• Current and planned long-baseline experiments
  need energies from 0.5 GeV to several GeV
• Neutrino cross sections poorly known at low
  energies ?mostly old bubble-chamber data
• MINERnA plans to measure neutrino nucleus cross
  sections with unprecedented statistics from 1
  20 GeV
• Neutral current p0 is a major background to ne
  appearance experiments

Main Injector Experiment for n-A
Note MiniBooNE. SciBooNE (and K2K) making these
measurements as well!
Current knowledge of CC cross sections NC cross
sections known to 50 at best
p0
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MINERvA Detector

• Fully active segmented scintillator detector
  5.87 tons
• Nuclear targets He, C, Fe and Pb
• MINOS Near Detector as muon catcher

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MINERnA Cross Section Goals

• Constrain charged-current quasi-elastic,
  resonance, coherent, DIS cross sections to 5
  (error on flux) for neutrino energies between 1
  and 20 GeV
• Measure neutral current cross sections to 10
• Note current uncertainties are
• QE 15-20
• resonance 20-40
• coherent 100
• expect 800,000 QE events
• Similar s for other modes

nmN ? m-p
5 flux error not included
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NOvA

• Second generation experiment in the NUMI beamline
• Accelerator upgrades will increase the NUMI beam
  power from 0.4 MW to 0.7 MW
• Monochromatic off-axis beam
• Fully active detector optimized for detection of
  nm ? ne oscillations
• Long baseline (810 km) gives sensitivity to
  neutrino mass hierarchy

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NOnA Detector

• Surface detector
• 15 kT of plastic (30) filled with liquid
  scintillator (70)
• Liquid scintillator read out by embedded fibers
• 385K cells, x and y
• Longitudinal sampling 0.15 X0
• ne efficiency 35

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NOvA What you see in the Detector
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NOvA Run Plan and Status

• Run Plan
• Run 3 years each on n and n-bar
• For 0.7 MW this is 36 X 1020 pot
• For 1.2 MW (superNUMI upgrade) this is 60 X 1020
  pot
• Project X would provide 2.3 MW beam and 120-240 X
  1020 pot

• Status
• Budget fiasco put project behind by several
  months
• Funding restored in August, 2008
• CD-3a just signed (Friday) Approve start of
  limited construction
• Aug 2012 partial detector online
• Jan 2014 full detector online

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NOvA Is q23 Maximal?

• Because of NOvAs good energy resolution, it will
  make a 1 measurement of q23 through muon
  neutrino disappearance

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NOvA What is q13?

• NOvA designed for good electron appearance
  sensitivity down to 0.01 level
• s(E)/E 10/vE for ne CC events

NOvA
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NOvA CP violation sensitivity

• NOvA will provide the first look into CP
  conservation

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NOvA Mass Hierarchy Sensitivity

• NOvAs long baseline makes it sensitive to the
  mass hierarchy due to the difference between
  s(nee-), s(nee-), s(nme-) in the earth

NOvA alone
NOvA T2K
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Longer-Range Future
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Fermilab Looks into the Future with no Collider
P. Oddone, HEPAP, Feb. 14, 2008
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Pushing the Intensity Limits with ProjectX
Project X Replace the 40-year old Booster with
a high intensity LINAC.
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Project X Proton Beam Power
Critical Decision 1 (CD-1) in 2010, leading to a
CD-2/3a in 2011
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P5 Panel Recommendations
The panel recommends a world-class neutrino
program as a core component of the US program,
with the long-term vision of a large detector in
the proposed DUSEL and a high-intensity neutrino
source at Fermilab.
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Consensus in the Neutrino Community Forming
U.S. Long Baseline Neutrino Experiment Study
(arXiv07054396) NUSAG Report, July 13, 2007

• DUSEL far detector site
• Longer baseline than NuMI
• Deep underground site being prepared
• Multi-purpose detector possible
• Wide band beam is best can fit oscillation
  parameters using energy spectrum
• Considerable upgrade to the current Fermilab
  intensity needed
• Water Cerenkov of multi-100kTon size is needed
• An equivalent sensitivity liquid argon TPC would
  be 1/3 the size

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Next Generation Detectors Being Designed
LENA 50kT
Glacier 10-100kT
MEMPHIS 215kT /shaft
UNO 500kT
LArTPC 50kT
LANND 122kT (8x8)
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Two Detector Technologies Favored
U.S. Long Baseline Neutrino Experiment Study
(arXiv07054396)
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Fermilab Pursuing Aggressive Liquid Argon Program
Bonnie Fleming
Similar program underway in Europe
Staged program for RD with physics increasing
with each step
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ArgoNeuT

• Joint NSF/DOE Liquid Argon TPC RD program
• 500 liter detector in NUMI beam
• Goals
• Demonstrate effectiveness of liquid argon
  purification techniques
• Measure gamma vs electron discrimination
• Measure low energy neutrino cross sections

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MicroBooNE

• 70/170 ton mass
• RD (stage 2 of LArTPC program)
• Test purity in a non-evacuated vessel
• Full systems test of low-noise electronics
• TPC and vessel design
• Physics
• Study surface running issues
• Investigate MiniBooNE low energy excess
• Measure neutrino cross sections
• BNB 100K events, NuMI 60K events
• Schedule
• Construction 2009
• Data 2011

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Fermilab Decision Path Y.K. Kim
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The Sensitivities of the Different Schemes
q13
Hierarchy
CPV
NUMI NOvA
NUMI NOvA5kT
NUMI NOvA5kTPX
NUMI 2x100kTPX
DUSEL 100kTPX
Niki Saoulidou, NUFACT08 Talk
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Ultimate Reach Neutrino Factory

• Advantages
• Large neutrino fluxes
• Little uncertainty in neutrino flux
• Little background if sign of lepton can be
  determined
• All n parameters measured from ne ?nm and anti-ne
  ? anti-nm
• Dm2 sensitivity so good that hierarchy may be
  measurable with q13 0!
• Disadvantages
• Need to measure muon sign ? magnetic detector
  needed
• Technology unproven lots of RD needed that
  will take time

International Design Study ZDR by 2010, RDR by
2012
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4 GeV Neutrino Factory
CPV
Mass Hierarchy

• Geer, Mena, Pascoli, Phys. Rev. D75, 093001,
  (2007).
• Bross, Ellis, Geer, Mena, Pascoli, hep-ph
  arXiv0709.3889

Bands indicate running time and background
uncertainties
Magnetic cavern with two parallel solenoids (0.5T
x 34,000 m3).
Superconducting transmission line designed for
VLHC
n
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The Future is very exciting, but. . .

• It isnt going to come cheap! A very crude
  estimate of the costs
• DUSEL 500M
• Fermilab beamline to DUSEL 250M
• Project X 1,000M
• A new detector for DUSEL 500M-1,000M
• Total 2,250M-2,750M
• Neutrino factory 2,100M-2,700M
• Note NOvA (beam upgrade) 270M
• Note US LHC 500M over a decade
• It is clear that an international effort is
  needed
• It is clear that this will be a decades-long
  program, unless we are lucky and q13 and d are
  large!

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But the Government is in a Generous Mood. . .