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