Status and Prospects of HARP

1
Status and Prospects of HARP

• Malcolm Ellis
• On behalf of the HARP Collaboration
• NuFact02
• Imperial College, July 2002

2
The HARP Collaboration
Università degli Studi e Sezione INFN, Bari,
Italy Rutherford Appleton Laboratory, Chilton,
Didcot, UK Institut für Physik, Universität
Dortmund, Germany Joint Institute for Nuclear
Research, JINR Dubna, Russia Università degli
Studi e Sezione INFN, Ferrara, Italy CERN,
Geneva, Switzerland Section de Physique,
Université de Genève, Switzerland Laboratori
Nazionali di Legnaro dell' INFN, Legnaro,
Italy Institut de Physique Nucléaire, UCL,
Louvain-la-Neuve, Belgium Università degli Studi
e Sezione INFN, Milano, Italy P.N. Lebedev
Institute of Physics (FIAN), Russian Academy of
Sciences, Moscow, Russia Institute for Nuclear
Research, Moscow, Russia
Università "Federico II" e Sezione INFN, Napoli,
Italy Nuclear and Astrophysics Laboratory,
University of Oxford, UK Università degli Studi e
Sezione INFN, Padova, Italy LPNHE, Université de
Paris VI et VII, Paris, France Institute for High
Energy Physics, Protvino, Russia Università "La
Sapienza" e Sezione INFN Roma I, Roma,
Italy Università degli Studi e Sezione INFN Roma
III, Roma, Italy Dept. of Physics, University of
Sheffield, UK Faculty of Physics, St Kliment
Ohridski University, Sofia, Bulgaria Institute
for Nuclear Research and Nuclear Energy, Academy
of Sciences, Sofia, Bulgaria Università di
Trieste e Sezione INFN, Trieste, Italy Univ. de
Valencia, Spain
3
Outline

• Motivation
• Timeline
• The Detector
• Data taking
• 2001
• 2002
• Software/Analysis
• Prospects

4
Motivation

• Neutrino Factory
• Atmospheric Neutrinos
• Monte Carlo
• K2K and MiniBooNE Experiments
• Aim
• Measure Hadronic ds/dPT/dPL over range of
  momenta, target Z and thickness
• Few accuracy over all phase space, requires 106
  events per setting and low systematics.

5
Timeline

• Proposed November 1999
• Approved February 2000
• Technical Run September 2000
• Data Taking
• Solid Targets 2001
• Solid Cryogenic Targets 2002

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The Detector

• Main Requirements
• Acceptance, PID, Redundancy
• Beam instrumentation provides tracking and PID of
  incoming particle.
• TPC surrounds target to provide close to 4p
  coverage.
• Forward Spectrometer covers insensitive region of
  TPC.
• PID completed with Cherenkov, TOF and
  Calorimetry.

7
The HARP Detector
8
Particle ID Coverage
TPC
TOF
Cherenkov
9
CERN PS East Hall
10
HARP in 2001
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Beam and Targets

• Beam
• 3 5 8 12 15 GeV/c
• Solid Targets
• Be, C, Al, Cu, Sn, Ta, Pb
• Thin (2)
• Thick (100)
• 5 Targets (New)
• MiniBooNE
• K2K
• Skew Copper
• Alignment
• Cryogenic Targets
• H2/D2 N2/O2

target tube target holder
Extrapolated position of MWPC tracks at the target
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Cryogenic Targets

• Targets 2cm diameter, 6cm long.
• Two distinct setups
• N2/O2 Mid July
• H2/D2 Early August
• Filling takes 4-6 hours.
• Emptying takes 1 hour.

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2001 Data Taking

• Completed 1/3 of Solid Target Programme

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2002 Data Taking

• Programme (May-September)
• Thick Targets
• 5 Targets ve and ve beams
• Remaining Solid Targets
• Cryogenic Targets (start 8th July)
• MiniBooNE Programme (12th August)
• K2K Programme (26th August)

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Trigger
Forward trigger plane (FTP)
Consequence 1/2 to 2/3 of our thin-target data
are non-interacting beam particles
?
beam
?
Inner Trigger Cilinder (ITC)

• Solution
• Non-Interacting Beam (NIB) veto counters under
  study
• 5 Targets

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Software Processes

• Stringent time schedule required adoption of
  software engineering standards.
• Domains identification dependency structure
  lead to
• definition of releasable units (libraries and
  source code),
• definition of working groups (and schedules),
• definition of ordering for unitsystem testing
  and for release.

17
Software/Analysis

• DAQ and detectors readout (DATE).
• Storage and retrieval of physics data and
  settings (Objectivity DB, AMS-HPSS
  interface).
• Framework including application manager,
  interfaces data exchange for the components,
  and event model (GAUDI).
• Physics Simulation Detector Model (GEANT4).
• Physics Reconstruction for all detectors.
• Online Monitoring Offline Calibration of
  detectors.
• User Interface and Event Display (ROOT).
• Foundation libs Utilities (STL, CLHEP).

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Beam Instrumentation

• Beam Particles tracked by 4 MWPCs
• Particle ID performed by
• Cherenkov, TOF, m identifier

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TPC

• Gas Choice 90 Ar, 10 C02
• Gas Speed 5cm/ms
• Total drift time 32 ms ? 320 time samples
• Cross-Talk problems under investigation

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TPC Reconstructed Tracks
PT vs PL for Thick Target Data
PT for all TPC Tracks
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RPCs
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RPC/TPC Matching

• RPC are fully efficient and noise-free
• RPC timing removes off-time tracks

2 mm stesalite wall
Target (fixed to the magnet)
(fixed to the TPC)
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NOMAD Drift Chambers

• Efficiency reduced due to change of gas
• 90 Ar, 9 CO2, 1 CH4
• Calibration and Alignment
• ongoing

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Cherenkov

• Gas Leakage problem emerged in the commissioning
  phase
• Support structure re-welded
• Epoxy-treatment of inner surfaces.
• Leak rate 4L/hour
• Specifications ? 4 L/hour.
• Density monitored by sonar
• techniques (acoustic wave phase shift) lt1
  precision.

Thresholds
? 2.6 GeV/c
? 9.3 GeV/c
p 17.6 GeV/c
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TOF Wall

• Calibration
• Laser
• Cosmic Rays
• Pulse Calibration

pions
protons
Example time separation and resolution for 3
GeV/c beam particles.
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Calorimeter

• Three modules 62 EM (4cm), 80 HAD (8cm) Muon
  Identifier
• Electron Identifier (EMHAD) 6.72m wide x 3.3m
  high.
• Muon Identifier is 6.44 Interaction Lengths of
  Iron and Scintillator slabs.

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Prospects

• Complete Data-Taking 30th September
• Analyses Initially Separated
• Large Angle (TPC/RPC)
• Small Angle (Forward Spectrometer)
• Expect to overcome TPC cross-talk problems, thus
  achieve design accuracy.
• Aiming for initial results by the end of this
  year.