Status dell’esperimento PANDA

Daniela Calvoon behalf of the PANDA collaboration

Sezione di Torino

SIF2011, Societa’ Italiana di Fisica - XCVII Congresso Nazionale

26-30 Settembre 2011, L’Aquila, Italy

Daniela Calvo

PANDA @ FAIR

The FAIR project

On October, 4th 2010,

the international owners

founded the FAIR GmbH.

The FAIR GmbH will coordinate the

construction of the accelerator and

experiment facilities. The participating

countries will contribute their technical and

scientific expertise to the project, in

addition to their financial and in–kind input.

Facility for Antiproton and Ion Research

UNILAC FRS

ESR

SIS 100

HESR

CRRESR

New

Existing

Proton linac

SIS 18

from RESR

Antiproton productionProton Linac 50 MeVAccelerate p in SIS18 / 100Produce p on targetCollect in CR, cool in RESR

High Energy Storage Ring

1011 stored antiprotons, momentum range 1.5 to 15 GeV/c

Luminosity at peak intensity: L = 2·1032 cm-2s-1 δp/p = 10-4

(stochastic cooling)

Luminosity for highest resolution: L = 2·1031 cm-2s-1 p/p < 4∙10-5

(electron cooling)

Extensively antiproton physics program

•Non perturbative QCD dynamics

• Hadrons in the Nuclear Medium

• Nucleon structure

• Electroweak Physics

• Charmonium spectroscopy

• Exotic states

• Hypernuclear physics

• Open charm physics

• D physics

Physics Performance Report for Strong Interaction Studies with Antiproton

Mar. 2009arXiv.org/abs/0903.3905v1

PANDA – modular multi-purpose device

• Excellent forward acceptance and resolution

• (Moderate) backward acceptance

• Wide dynamic range: particle momenta 0.1 - 8 GeV/c

• Momentum measurements in magnetic fields (Dp/p 1%)

• Particle ID in wide momentum range e, m, p, K, p, …

• Electromagnetic calorimeter: g, p0, h ... (e)

• High-resolution vertex detection: D, D0 / Ks, Λ, Σ, Ω ...

• High average interaction rate 2·107 ann/s-1

• Intelligent trigger design for parallel data acquisition at

high rates and small branching fractions

• Modular setup for double hypernuclei study

Timelines

Presented @ HZDR Workshop, Rossendorf, 6/9/11, by G. Rosner

20122011 2013 201620152014

6

Building permits

Site preparation

Civil construction contracts

Building of accelerator & detector

components

Completion of civil construction work

Installation of accelerators and detectors

Data taking

7 108

2017 2018 2019

12

6

7

8

9

11

12

10

119 Experiments

• Submit Pre-construction MoUs 1/7/2011

• Finish R&D phase 2011/12

– Deliver prototypes of all essential parts of detectors

• Submit complete sets of TDRs 2011/12

– Take decisions on alternative technical solutions

• Co-ordinate with 2011/12

– Civil construction requirements

– Accelerator setup schedule

• Identify critical pathways 2011/12

– Milestones, timelines, deliverables

• Submit risk management plan 2011/12

• Secure funding 2011/12

• Submit Construction MoUs end of 2012

FAIR

• (Europe-wide) tendering 2013

• Build detector 2013-16

• Submit Operations MoUs 2016

• Commission experiments 2017/18

• Initial period of data taking 2018-21Presented @ FAIR BFCl,

Darmstadt, 5/9/11, by G. Roesner

Daniela Calvo

Overview

The PANDA apparatus

Magnets and EM calorimeter progress

Ongoing Technical Design Reports:

• Target system

•MicroVertexDetector

• Straw Tubes - central tracker

• Muon detector

News on some other detectors:

Forward tracker

Hypernuclear setup

Conclusions

PANDA apparatus

p

12 m

EM calorimeter

TOFDIRC Cherenkov

Shashlik

calorimeterRICH

Straw chambers

µ counters

STTMVD

target

PANDA is a fixed target experiment with frozen

hydrogen and heavier nuclear targets (N, Au..)

Pellet target / Cluster-jet target/ Wires

GEM

µ counters

Target spectrometer

Forward spectrometer

Magnets

Technical documentation to call for the tenders for the construction is in progress

The 2 Tm DIPOLE

• acceptance: ±5° (V) and ±10° (H)

• air gap: 2.5m (z), 3.1m (x), 1 m (y)

•good uniformity in the air gap, at max. field

• the deflection of antiproton crossing at the

center is 2.2 ° (@ 15 GeV)

The 2T solenoid

• ~ 3 m long and ~1 m radius

• coil interruption to allow target

operation

•Nb/Ti superconductor @ 5000 A

nominal current

• field quality on the tracker:

± 2% in 150 < r <420 mm and

-400 < z < 1100 mm

<2 mm Br/Bz integral in the same

volume

• the solenoid can be operated at

every current lower than the nominal

one

• the iron return joke will be laminated

to host 13 layers of muon chambers

All the crystals for the forward end-cap have been bougth: 23 % of the whole EMC

• 15552 PWO-II crystals (light yield: 2xCMS)

• inner radius of barrel 57 cm

• thickness 22Xo

• cooled down to -25°C (light yield: 4xT=25°C)

• energy resolution: 1.54%/ √E[GeV]+0.3%

• Photosensors:

• Large Area Avalanche Photodiodes

(LAAPDs) (barrel), two each cristal

• Vacuum Photo-Triodes (VPTs) (end-

cap)

2cm x 2cm x 20cm

EM calorimeter

Module threshold is 0.75 MeV

Daniela Calvo

Ongoing TDRs

Carbon fiber

cylindrical frame Target pipe

Beam pipe

Conical structure

to support pixel barrels Frame to support disks

30

cm

40 cm

Micro Vertex Detector

Readout channels:

~ 11 million (pixel:

100mm x 100mm))

~ 200.000 (strip)

4 barrels

Two inner layers:

hybrid pixel detectors

Two outer layers:

double sided silicon strip

detectors

and 6 forward disks

Four disks:

hybrid pixel detectors

Then two disks:

Mixed pixel and strips

PID

MVD: material budget and rate

Max bit rate: ~450 Mb/s per pixel readout chip

(12760 readout cells – 100mm x 100mm pixel size)

Pixel readout: (ToPix)130 nm CMOS technology

MVD: spatial resolution

zxy z 65 mm

15 GeV/c• Primary vertex resolution

• Vertex resolution

Primary and secondary vertex resolution:

x,y 35 mm

z 100 mm

(6.57 / 7.50 / 8.50) GeV/c

STT – central tracker

• 4636 Straw tubes in 2 semi barrels around beam/target cross-pipe

• 23-27 planar layers in 6 exagonal sectors

– 15-19 axial layers in beam direction

– 4 stereo double-layers for 3D reconstr., with +- 2.89° skew

angle

• Time readout (isochrone radius)

• Amplitude readout (energy loss)

• Rin/Rout: 150/418 mm

• Al-mylar film, s= 27 mm, d=10 mm, L=1500mm

• 20 mm sense wire (W/Re, gold plated)

• 2.5 weight/tube

• X/Xo= 4.4x 10-4 /tube

• Straw tubed are assembled under overpressure (Dp=1bar)

• Strong rigidity: multi layer straw module is self supporting

• Perfect and strong cylindrical tube shape by inner gas overpressure

• rf ~ 150 (100) mm, z ~ 3 (2) mm (single hit)

• E/E <8% for p/k identification

• p/p ~ 1-2 % at B=2T

STT+MVD+GEM Pattern Recognition

! "#$%&(*/) 34(-*. 9"&-! J J (M%+#&STT alone Pattern recognition

STT: momentum resolution

Simulation parameters:

•5000 single muon events each point.

•Fixed total momentum 0.3, 1, 1.5, 2 GeV/c

•θ: [5° - 25°] in steps 2° ; [25° - 160°] in steps 5°

•ϕ Uniform: [0° - 360°]

STT : energy loss resolution

Test beams at 3 different proton momenta

– 2.9 GeV/c, 1.0 GeV/c, 640 MeV/c

– dE/dx resolution (30% truncation)

• dE/E = 9.3 % at 2.9 GeV/c

• dE/E = 8.1 % at 1.0 GeV/c

• dE/E = 7.0 % at 640 MeV/c

(Rev. of Part.Phys, 2010)

STT : spatial resolution and reconstruction efficiency

Ar/CO2(20%)

1.25bar

STT capabilities

Efficiency of the STT alone Pattern Recognition 95% -> 100%

(0.3- 10 Gev/c protons, 1-10 tracks for event)

-> 37 layers Mini Drift Tubes

• Proportional mode operation

• Induced signal on external strips

• ~ 4k MDT, 30 kwire, 75 kstrips

Muon detector

• 1 cm wide, 10 cm long strips

• 4 MDT layers

• near vertical tracks

σ~0.4 mm

Daniela Calvo

Some other detectors

Forward tracker

6 Tracking stations:

2 before, 2 inside and 2 after dipole magnet

based on 1 cm 2bar pressure straw tubes

Each tracking station contains four double-

layers:

two with vertical straws

two tilted by ±5°

Angular acceptance:

±5º vertically,

±10º horizontally

Momentum acceptance down to ~2% of pbeam

Momentum resolution: ~0.5%

Double hypernuclei- modular setup

by cortesy of D. Rodriguez

Secondary target

Si m-Strip +

Be,B,C absorbers

Diamond

Diamondwire

Si ring

Dimensions – primary target

•Si ring outer f =15 mm

•Si ring inner f = 11 mm

•Diamond thickness = 3 mm

•Diamond wire width = 100 mm

primary 12C

target

Daniela Calvo

Conclusion

• PANDA apparatus is a general purpose detector

• High rates, high precision, various targets

• The production phase is already started for the EMC

• The R&D phase is ongoing to finish

• Most of TDR will be released by the end of 2011, the

rest within 2012

Institutes

+ as new entry at the last Panda meeting of September: Bhaba Atomic Research Center (BARC)(India), Suranee University of Technology (SUT) (Thailand), LNL (Italy),

More than 400 physicists from 53 institutions in 16 countries

U BaselIHEP Beijing

U BochumIIT Bombay

U BonnIFIN-HH BucharestU & INFN BresciaU & INFN Catania

JU CracowTU Cracow

IFJ PAN CracowGSI Darmstadt

TU DresdenJINR Dubna

(LIT,LPP,VBLHE)U EdinburghU Erlangen

NWU Evanston

U & INFN FerraraU Frankfurt

LNF-INFN FrascatiU & INFN Genova

U GlasgowU Gießen

KVI GroningenIKP Jülich I + II

U KatowiceIMP Lanzhou

U LundU MainzU Minsk

ITEP Moscow MPEI MoscowTU München

U MünsterBINP Novosibirsk

IPN OrsayU & INFN PaviaIHEP ProtvinoPNPI Gatchina

U of SilesiaU Stockholm

KTH StockholmU & INFN Torino

Politechnico di TorinoU & INFN Trieste

U TübingenTSL Uppsala

U UppsalaU ValenciaSMI Vienna

SINS WarsawTU Warsaw

Shashlyk calorimeter

• 7 m from the interaction point

• active area: 2970mm x 1540mm

• Supermodule number: 374

• 4 modules in a supermodule

• Energy resolution: E/E= 3.5/E + 2.4/√E

+1.3[%], E in GeV

MODULE

• 380 layers of 0.3mm lead and 1.5 mm scintillator

• 55mm x 55mm transverse size

• total lenght: 680mm

• total radiation length: 20 Xo

• Moliere radius: 59mm

• light collection: 36 WLS fibers (1 mm diameter)

• photodetector: PMT

Daniela Calvo

Conclusion

• Integrated luminosity @ 2x 1032 cm-2 s-1 (50% efficiency)

• ~ 8 pb-1/ day

• ~ 3 fb-1/ year

• Reconstructed events per year

• 2 x 107 C2

• 2 x 107 DDbar

• 2 x 108 XXbar

• 2 x 109 J/Y

• Fine scan to measure masses with DM~50 KeV and G~ 10%

ε ≈ 40%> 5∙104 events

per

PANDA year

Charmonium States

Hypernuclei production probability - 13LLB

X- + 12C 13LLB*

: Double-Hypernuclei

: Single-Hypernuclei

: Twin-Hypernuclei

: LL

production of excited states of Double Hypernuclei is significant

PLB 697 (2011) 222- 228