NA61/SHINE detector and its capabilities

Wojciech DOMINIKSHIN(E)ing Physics , December 6, 2008

Beam Tracking - TPC Particle identification Calorimetry- PSD

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NA49

SPS

LHC

LHC

SPS

NA61/SHINE

NA61/SHINE at the CERN SPS

S. Afanasiev , et al. (NA49 Collaboration), Nuclear Instruments and Methods A430 (1999) 210

NA49 apparatus

Successfully operated until 2002

NA49 facility:Large acceptance: ≈80% @158GeV

High momentum resolution:

Good particle identification:

Tested in 2006 and 2007 runs:

High detection efficiency: > 95%

No degradation of the performance since the beginning of operationReconstruction, calibration, simulation and analysis software worksAll necessary experts are in the collaboration

Report from the test run: CERN-SPSC-2006-023, SPSC-SR-010(September 5, 2006)

Precise and rich physics results: 37 publications with final data

TOF 60 ps ,dE dx dE dx 0.04 ,

m inv 5MeV

p p 2 10 4 GeV c 1

NA61 and basic upgrades:

Upgraded NA49 apparatus

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

Basic upgrades:

2011: Projectile Spectator Detector: an increase of the resolution in the measurement of the number

of projectile spectators by a factor ≈5 to ∆E/E ≈ 50%/E,

Installation of the Helium beam pipe in the VTPC cage reduction of the delta-electron background by a factor of 10

2008: Replacement of the TPC digital read-out and DAQ: an increase of the event rate by about 20 to 80 Hz

2007: Modification and replacement of obsolete equipment, construction of the forward ToF wall re-establish the full functionality of NA49

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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

Secondary hadron beams for NA61:

Beam Position Detectors

3 x 3 cm2 proportional chambers with cathode strip readout

Two orthogonal sense wire planes (15 μm tungsten wires with 2 mm pitch)

Central cathode plane and cathode strip planes and windows are made of 25 μm aluminized Mylar

Operated withAr/CO290/10 gas mixture

Tracking detectors - Time projection Chamber (TPC)

TPC - tracking of charged particles180 000 sampling pixels for all TPC's62 MWPC modules

Main Time Projection Chamber * 2readout surface of 3.9x3.9 m2 depth of the field cage of 1.1 mgas mixture: Ar+CO2+CH4 → Ar+CO2 (94/6)up to 90 measured points on a trajectory25 proportional chambers

Vertex Time Projection Chamber * 2gasbox of 2.0x2.5 m2 surface area Depth of field cage 0.67 m gas mixture: Ar/Ne+CO2 (90/10)6 proportional chambers up to 72 measured points on a trajectoryMagnetic field – up to 1.5 Tesla

The 2007 pilot run:

p+C at 31 GeV/c

Particle identification by dE/dx measurementNA49

p+p

p+Pb

NA61 2007 pC data

Particle identification by combined dE/dx and TOF measurement

NA49Pb+Pb collisions momentum range 5–6 GeV/c

NA61 2007 pC data

Precise determination of the number of projectile spectators in the NA61 ion

programmeMeasurement of centrality: b~ A - Nspect (selection of centrality at trigger level)Measurement of event-by-event

fluctuations (to exclude the fluctuation of participants)Reconstruction of the reaction plane

high granularity: 12 x 9 array of modules (10x10x125 cm3)transverse homogeneity of energy resolution, compensated calorimeter (e/h = 1), lead/scintillator sampling

ratio 4:1 high energy resolution ~50%/sqrt(E) should be achievedlongitudinal segmentation (10 sections per modulecalibration, improve energy resolutionlight readout from each sections by novel MAPDs provide large dynamic range(range of the detected energies – 10-30000 GeV)

Role of the PSD in NA61

Projectile Spectator Detector (PSD) – NA61 calorimeter

Main features of the PSD

Single PSD module:

60 lead/scintillator sandwiches 10 longitudinal sections 6 WLS-fiber/MAPD 10 MAPDs/module 10 Amplifiers with gain~40

MAPDs and amplifiers.

F. Guber, A. Ivashkin - INR, Moscow

Projectile Spectator Detector – NA61 calorimeter NA61

R 50

h

Substrate

MATRIX OF INDEPENDENT GEIGER PHOTODIODE PIXELS

NAMED :SILICON PHOTOMULTIPLIER (SiPM)MULTI-PIXEL PHOTON COUNTER (MPPC)AVALANCHE MICROCHANNEL PHOTODIODE (AMPD)GEIGER MODE AVALANCHE PHOTODIODES (G-APD)MULTIPIXEL AVALANCHE PHOTODIODE (MAPD)

- SINGLE PHOTON SENSITIVITY- VERY GOOD TIME RESOLUTION: 50-100 ps- “PROPORTIONAL” TO INPUT SIGNAL - HIGH Q.E. ~ 80% (POTENTIALLY) - OPERATION IN HIGH MAGNETIC FIELD- LOW COSTHIGH SINGLE ELECTRON NOISE (100 kHz-1MHz)

SiPM - SOLID STATE PHOTON DETECTORSFirst proposed by Golovin and Sadygov in the 90’s

G. COLLAZUOL (ITC-irst)INFN Pisa2007

Properties of MAPDs

New generation of micro-pixel APD produced in Singapore by Zecotek

- Active area: 3x3 mm2

- Number of pixel: up to 40000/mm2

- Gain ~ few x 104

- Voltage ~65 V- Dark current ~50 nA- High stability

Module assembling at INR

Calibration of modules with 75 GeV muon beam (2007)

Run 5362 mod 1

l.y~2ph.e/MeV

Performance of PSD supermodule2007 hadron data

Energy resolution of 3x3 prototype: stochastic term ~ 54% constant term ~ 1.9%

…progress in MAPDs development since beginning of 2008

1. Photon detection efficiency (PDE):

420nm 550nm MAPD3A 12% 20%New MAPD3 23% 37%

2. Signal shape: new MAPD3 MAPD3A

-rise time 7 ns 10 ns-full width 40 ns 50 ns

F. Guber, A. Ivashkin - INR, Moscow

Two proposed options of the PSD structure

-108 modules,- Each module ~ 125 kG- can be used for reaction plane meas?- Total cost about 1 000 000 CHF

- 40 modules (20 small +20 large ones)- Each large module ~ 500 kG!!- can be used for reaction plane meas?-Total cost about 670 000 CHF

option 1 option 2

F. Guber, A. Ivashkin - INR, Moscow

Large acceptance: ≈50%High momentum resolution:

p p 2 10 4 GeV c 1

Good particle identification:

High detector efficiency: > 95%

Performance of the NA61 detector:

Results of the 2007 run:

at full magnetic field

TOF 100 ps ,dE dx dE dx 0.04,

m inv 5MeV

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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