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M. Gazdzicki, Frankfurt, Kielcefor the NA61 Collaboration

NA61/SHINE: 2008 Status Report

Fundamentals

Next 12 months

2007 data calibration and analysis2008 run

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Physics goals:

Search for the critical point of strongly interacting matter

Study the properties of the onset of deconfinement in nucleus-nucleus collisions

Physics of strongly interacting matter

Measure hadron productionat high transverse momentain p+p and p+Pb collisions asreference for Pb+Pb results

Precision measurements:

Discovery potential:

Fundamentals

Data for neutrino and cosmic ray experiments

Measure hadron productionin the T2K target needed for

the T2K (neutrino) physics

Measure hadron production in p+C interactions needed

for T2K and cosmic-ray, Pierre Auger Observatory

and KASCADE, experiments

Precision measurements:

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The NA61/SHINE Collaboration:121 physicists from 24 institutes and 14 countries:

University of Athens, Athens, GreeceUniversity of Bergen, Bergen, NorwayUniversity of Bern, Bern, Switzerland KFKI IPNP, Budapest, HungaryCape Town University, Cape Town, South AfricaJagiellonian University, Cracow, PolandJoint Institute for Nuclear Research, Dubna, RussiaFachhochschule Frankfurt, Frankfurt, GermanyUniversity of Frankfurt, Frankfurt, GermanyUniversity of Geneva, Geneva, SwitzerlandForschungszentrum Karlsruhe, Karlsruhe, GermanySwietokrzyska Academy, Kielce, PolandInstitute for Nuclear Research, Moscow, RussiaLPNHE, Universites de Paris VI et VII, Paris, FrancePusan National University, Pusan, Republic of KoreaFaculty of Physics, University of Sofia, Sofia, BulgariaSt. Petersburg State University, St. Petersburg, RussiaState University of New York, Stony Brook, USAKEK, Tsukuba, JapanSoltan Institute for Nuclear Studies, Warsaw, Poland Warsaw University of Technology, Warsaw, PolandUniversity of Warsaw, Warsaw, PolandRudjer Boskovic Institute, Zagreb, CroatiaETH Zurich, Zurich, Switzerland

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Detector

Upgraded NA49 apparatus

NA49: Nucl. Instrum. Meth. A430, 210 (1999) Upgrades: CERN-SPSC-2006-034, SPSC-P-330

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Addendum-3 CERN-SPSC-2007-033, SPSC-P-330 (November 16, 2007)Addendum-2: CERN-SPSC-2007-019, SPSC-P-330 (June 15, 2007)Addendum-1: CERN-SPSC-2007-004, SPSC-P-330 (January 25, 2007)Proposal: CERN-SPSC-2006-034, SPSC-P-330 (November 3, 2006)Status Report: CERN-SPSC-2006-023, SPSC-SR-010 (September 5, 2006) LoI: CERN-SPSC-2006-001, SPSC-I-235 (January 6, 2006)EoI: CERN-SPSC-2003-031, SPSC-EOI-001 (November 21, 2003)

Status Report: CERN-SPSC-2008-018, SPSC-SR-033 (July 2, 2008)

Documents:

Report from the NA61/SHINE experiment at the CERN SPS, CERN-OPEN-2008-012 Na61/Shine at the CERN SPS, CPOD 2007, arXiv:0709.1867

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2007 data calibration and analysis

2007 run: September 27 – October 29:

-test of the PSD super-module with beams of muons and hadrons,

-optimization of the proton beam at 31 GeV/c,

-pilot data taking with 31 GeV/c protons on the thin (2 cm) C target,

-pilot data taking with 31 GeV/c protons on the T2K replica C target,

-TPC read-out test with the ''FE Tester''

1.5 • 106 events registered for the NA61 physics programme:

- 640 k events with the thin target, - 230 k events with the T2K replica target - 80 k events without target

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Organization and manpower:

-weekly EVO meetings on the software and calibration,

-weekly EVO meetings on the analysis,

-two analysis meeting organized in Warsaw and at CERN,

-two collaboration meetings at CERN,

The manpower involved in the software, calibration andanalysis effort corresponds to the plan presented in Addendum-2

Bravar, Fodor, Popov, Stefanek, + ...

The NA61 software libraries and infrastructure were establishedbased on the NA49 software

Meregaglia, Popov, Stefanek, Szuba, + ...

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Data calibration and quality assessment:

The calibration procedure consist of several steps resultingin optimized parameters for:

-detector geometry, drift velocity and residual corrections,

-magnetic field calibration,

-time of flight measurements,

-specific energy loss measurements.

Each step involves reconstruction of required data followedby optimization and verification procedures

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Geometry and drift velocity calibration:Residuals before and after calibration for:

before after

-detector geometry,-drift velocity,-residual distortions

Anticic, Susa, + ...

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Magnetic field calibration:invariant mass spectra used for the calibration

K0s

and the calibration factor

Wojtaszek, + ...

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Time of flight measurements:ToF-F and ToF-L/R resolution after calibration for:

ToF-F ToF-L/R /√2 = 126 ps

time difference between two overlapping scintillators

time difference between measured and calculated

values

-detector geometry,-time off-set

Kolesnikov, Murphy, + ...

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Specific energy loss measurements:dE/dx resolution after calibration for:

(dE/dx)/dE/dx = 4-5 %

-time dependence of the gas pressure,-residual time dependence,-charge absorption during the drift,-differences in the sector gains,-differences in the amplification in the preamplifiers,-edge effects at sector boundaries

Abgrall, Fodor, + ...

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Monitoring and QA software development:Obsolete NA49 packages for monitoring and QA were replaced by corresponding new packages developed by NA61 for: -preparation of QA histograms and scalers for each detector and reconstruction software module, -filling the plots for each DST file during the production, -fast visualization and semi-automatic monitoring of each QA plot as a function of time

Sadovsky, + ...

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-event visualization of data after different stages of reconstruction and in different formats

Ionita, Maris, Ulrich, Unger, + ...

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Trigger and cross-section:Beam and trigger counters

C1 and C2 - proton identification,S1, S2, V0, V1, BPD1/2/3 – determination of proton trajectory,S4 – selection of p+target interactions

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Proton beam properties:momentum from TPC

beam spot from BPD-3

dE/dx from TPCall beam particles

triggered protons

p

p

Marcinek, Marchionni, Meregaglia, Planeta, Popov, Strabel, + ...

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Inelastic cross section for p+C at 31 GeV/c:

derived from the measured by NA61 trigger cross section and corrected using GEANT4 simulation for:

-a contribution of elastic interactions due to a large angle scattering,-a loss of inelastic events when a secondary particle (proton, pion or kaon) hits the S4 counter

stat

istica

l erro

rs o

nly

PRELIMINARY

Marchionni, Meregaglia, Strabel, + ...

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Detector performance and raw spectra:Tracking performance:

TPC cluster parameters Momentum fit Vertex fit

T2K replica vertex fit

Aduszkiewicz, Popov, Stefanek, Susa, + ...

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Negatively charged hadrons:

Pions which produce neutrinosmeasured by Super-Kamiokande

Negatively charged hadronraw yield measured by NA61

= h- - small(5%) corrections

Palczewski, Stepaniak, + ...

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Particle identification by decay topology measurements:Podolanski-Armenteros plot

for V0 candidates

K0s

Invariant mass spectrum for V0 candidates

V0 raw yield measured by NA61

Tomeszewski, + ...

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Particle identification by dE/dx measurements:

Abgrall, Posiadala, + ...

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Particle identification by tof measurements:ToF-F raw spectrum

1 < p < 3 GeV/c

ToF-L/R raw spectrum

Kolesnikov, Murphy, + ...

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Particle identification by combined dE/dx and tof measurements:

2 < p < 3 GeV/c 4 < p < 5 GeV/c

K+

ToF-F and TPCs

Murphy, + ...

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Simulation and corrections:The corrections to the raw spectra are calculated using the NA61 simulation chain which includes:

-event generation (VENUS, ...),-particle propagation through the detector (GEANT 3.21),-distortions and TPC digitization,-embedding of the simulated raw data to real events,-reconstruction of the simulated data

Example of acceptance studies

Abgrall, + ...

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Test of the PSD super-module (array of 3x3 modules):PSD = Projectile Spectator DetectorModular compensating lead/scintillatorcalorimeter with the MAPD optical read-outNeeded for a precise determinationof the number of projectile spectatorsin the NA61 ion programme

energy spectra: data and simulation Extrapolated energy resolution for Pb+Pb collisions at 158A GeV

Golubeva, Guber, Ivashkin, + ...

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2008 runAugust 28 – September 4: test of the PSD prototype, commissioning of the new beam position detectors,

September 5 – September 25: beam/trigger tunning, installation and commissioning of the TPC read-out and DAQ upgrade,

September 26 – October 30: data takingTPC read-out and DAQ upgrade:

-new TPC read-out electronics and DAQ designed and tested in 2008,-total cost 400 k CHF,-the production of the new electronics is almost completed,-the installation and commissioning is scheduled for September 10-25

NA61 Budapest group, + ...

-crucial for the NA61 physics programme (x10 event rate),

A new motherboard (one out of 250)

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Next 12 months

- Further analysis of the 2007 data: main goal: pion and kaon spectra for T2K and C-R physics,- The 2008 run: focused on T2K and C-R requests, - Calibration and analysis of the 2008 data,- The 2009 run: focused on the energy scan and high pT, test of the PSD hyper-module (array of 5x4 modules)

- Addendum to the proposal with the updated data taking schedule should be submitted for the next SPSC meeting It will be based on the memorandum between NA61 and AB Department and it will assume:

-2009-2010: runs with proton beam,

-2011-2013: runs with secondary ion beams produced from the primary Pb beam (compatibility with I-LHC)

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Summary I-NA61 was approved at CERN in June 2007,

-the pilot run was performed during October 2007,

-calibration of all detector components have been performed successfully

-preliminary uncorrected spectra have been obtained,

-high quality of track reconstruction and particle identification similar to NA49 has been achieved,

-a preliminary result on the total inelastic p+C cross section at 31 GeV/c was obtained,

-the data and detailed simulations confirm that the phase-space needed for the T2K measurements is covered,

-the PSD super-module test demonstrated that the required energy resolution is reached.

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Summary II-the TPC read-out and DAQ upgrade essential for all NA61 physics programmes has been designed and prototypes have been successfully tested,

-the 2008 has started with the PSD prototype test and commissioning of the new BPD detectors,

-the TPC upgrade shall be installed and commissioned by September 25, when the data taking shall start.

-the updated data taking schedule for 2009-2013 is under preparation, it assumes use of the secondary ion beams from 2011 which allows to reach a compatibility with I-LHC.

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Request to CERN

-CERN does not participate in NA61,

-maintenance of the large and complicated NA61 apparatus requires a dedicated personnel constantly present at CERN, the corresponding expenses are too high to be covered by the collaborating institutions,

-a support from CERN, which allows to increase NA61 presence at CERN, is necessary to preserve high running efficiency for the next years,

-this can be reached by: -a dedicated to NA61 (part time) CERN detector/technical personnel, -NA61 CERN fellows and associates -...

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Additional slides

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The 2007 pilot run:

Additional ToF

PSD prototype

Upgrades

R&D

Data

p+C at 31 GeV/c

on thin target and

T2K replica target

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Facility: SPS RHIC NICA SIS-300

Exp.: NA61 STAR MPD CBM PHENIX

Start: 2011 2011 2014 2016

Pb Energy: 4.9-17.3 4.9-50 ≤9 ≤8.5(GeV/(N+N))

Event rate: 100 Hz 1 Hz(?) ≤10 kHz ≤10 MHz(at 8 GeV)

Physics: CP&OD CP&OD OD&HDM OD&HDM

CP – critical pointOD – onset of deconfinement, mixed phase, 1st order PTHDM – hadrons in dense matter

Experimental landscape of complementary programsof nucleus-nucleus collisions around the SPS energies

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Experimental landscape of complementary programsof nucleus-nucleus collisions around the SPS energies