Status and Prospects of HARPStatus and Prospects of HARP

Malcolm Ellis

On behalf of the HARP Collaboration

NuFact02

Imperial College, July 2002

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The HARP Collaboration: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

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OutlineOutline

Motivation Timeline The Detector Data taking:

– 2001– 2002

Software/Analysis Prospects

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MotivationMotivation

Neutrino Factory Atmospheric Neutrinos Monte Carlo K2K and MiniBooNE Experiments Aim:

– Measure Hadronic d/dPT/dPL over range of momenta, target Z and thickness

– Few% accuracy over all phase space, requires ~106 events per setting and low systematics.

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TimelineTimeline

Proposed: November 1999Approved: February 2000Technical Run: September 2000Data Taking:

– Solid Targets: 2001– Solid & Cryogenic Targets: 2002

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The DetectorThe Detector

Main Requirements:– Acceptance, PID, Redundancy

Beam instrumentation provides tracking and PID of incoming particle.

TPC surrounds target to provide close to 4 coverage.

Forward Spectrometer covers insensitive region of TPC.

PID completed with Cherenkov, TOF and Calorimetry.

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The HARP DetectorThe HARP Detector

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Particle ID CoverageParticle ID Coverage

TPCTPC

TOFTOF

CherenkovCherenkov

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CERN PS East HallCERN PS East Hall

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HARP in 2001HARP in 2001

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Beam and TargetsBeam and Targets

target tubetarget holder

Extrapolated positionof MWPC tracks at the target

Beam:• ±3 ±5 ±8 ±12 ±15 GeV/cSolid Targets:• Be, C, Al, Cu, Sn, Ta, Pb• Thin (2%)• Thick (100%)• 5% Targets (New)• MiniBooNE• K2K• Skew Copper• AlignmentCryogenic Targets:• H2/D2 N2/O2

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Cryogenic TargetsCryogenic Targets

element H2 D2 N2 O2

boiling temp. 20.4 K 23.6 K 77.4 K 99.2 K

# 0.84 % 2.13 % 5.52 % 7.52 %

•Targets 2cm diameter, 6cm long.•Two distinct setups:

N2/O2 – Mid JulyH2/D2 – Early August

•Filling takes 4-6 hours.•Emptying takes ~1 hour.

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2001 Data Taking2001 Data Taking

Completed 1/3 of Solid Target Programme:

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2002 Data Taking2002 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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TriggerTrigger

beam

Forward trigger plane (FTP)

Inner Trigger Cilinder (ITC)

Consequence: 1/2 to 2/3 of our thin-target data are non-interacting beam particles

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

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Software ProcessesSoftware 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 unit&system testing and for release.

DetResponseDetResponse

HarpUIHarpUI

ObjyHarpObjyHarp

ReconstructionReconstruction

ObjectCnvObjectCnv

ROOT ROOT GEANT4GEANT4

DetRepDetRep

GaudiFramework

GaudiFramework

HarpEventHarpEventHarpDDHarpDD

CLHEP+ STL

CLHEP+ STL

DAQDAQ

SimulationSimulation

DATEDATE

EventSelector

EventSelector

ObjyPersistency

ObjyPersistency

HEPODBMSObjectivity

HEPODBMSObjectivity

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Software/AnalysisSoftware/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 InstrumentationBeam Instrumentation

•Beam Particles tracked by 4 MWPCs•Particle ID performed by:

•Cherenkov, TOF, identifier

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TPCTPC

•Gas Choice: 90% Ar, 10% C02

•Gas Speed 5cm/s•Total drift time: 32 s 320 time samples•Cross-Talk problems under investigation

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TPC – Reconstructed TracksTPC – Reconstructed Tracks

PT vs PL for Thick Target DataPT for all TPC Tracks

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RPCsRPCs

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RPC/TPC MatchingRPC/TPC Matching

2 mm stesalite wallTarget (fixed to the magnet)

(fixed to the TPC)

• RPC are fully efficient and noise-free

• RPC timing removes off-time tracks

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NOMAD Drift ChambersNOMAD Drift Chambers

•Efficiency reduced due to change of gas: •90% Ar, 9% CO2, 1% CH4

•Calibration and Alignment ongoing

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CherenkovCherenkov

2.6 GeV/c

9.3 GeV/c

p 17.6 GeV/c

Thresholds:

•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 sonartechniques (acoustic wave phase shift) <1% precision.

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TOF WallTOF Wall

pions

protons

•Calibration:•Laser•Cosmic Rays•Pulse Calibration

Example: time separationand resolution for 3 GeV/cbeam particles.

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CalorimeterCalorimeter

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

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ProspectsProspects

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.