The PANDA ExperimentThe PANDA Experiment

at FAIRat FAIR

Marco Destefanis Università degli Studi di Torino

Hadron Structure 2013

Tatranské Matliare (Slovakia)June 30- July 04, 2013

for the PANDA Collaboration

OverviewOverview

• Physics topics @ PANDA

• Form Factors

• Drell-Yan process and background

• Hypernuclei

• PANDA spectrometer

• Summary

Primary beams:• Proton• Heavy Ions• Factor 100-1000 over present in intensity

Future GSI andFuture GSI andFacility for Antiproton Facility for Antiproton

and Ion Researchand Ion Research

Secondary Beams:• Radioactive beams• Antiprotons 3 - 30 GeV 1-2 107 /s

Storage and Cooler Rings:

• Radioactive beams• e – A collider

• 1011 stored and cooled

0.8 - 14.5 GeV antiprotons

High Energy Storage High Energy Storage RingRing

HESR

High res. mode: L = 1031 cm-2 s-1 p/p < 10-5

High lum. mode: L = 2·1032 cm-2 s-1 p/p < 10-4

Cooling: electron/stochastic

Pmax = 15 GeV/cLmax = 2·1032 cm-2 s-1

Ø < 100 mp/p < 10-5

internal target

Characteristics

1011 stored and cooled 0.8-15 GeV/c antiprotons

Antiproton powerAntiproton powerpbar beams can be cooled -> excellent resonance resolution

Preliminary expectation

The PANDA PhysicsThe PANDA Physics

• Confinement Why are there no free quarks?

• Hadron mass Where is the mass of the proton coming from?

• Are there other color neutral objects?

• What is the structure of the nucleon?

• What are the spin degrees of freedom?

J. Ritman, Status of PANDA, 8th International Workshop on Heavy Quarkonium 2011

• Meson spectroscopy*: • D mesons• charmonium • glueballs, hybrids, tetraquarks, molecules

• Charmed and multi-strange baryon spectroscopy*

• Electromagnetic processes (FF, pp→e+e-, pp→, Drell-Yan)

• Properties of single and double hypernuclei

• Properties of hadrons in nuclear matter

The PANDA PhysicsThe PANDA Physics

* Presented by V. Mochalov

ppbar Cross Sectionppbar Cross Section

ppbar Cross Section–Exclusive Final ppbar Cross Section–Exclusive Final StatesStates

The PANDA PotentialThe PANDA Potential

• All JPC allowed for qq are accessible in pp

T. Johansson, PANDA at FAIR, Excited QCD 2012, Peniche (Portugal)

Formation

• JPC not allowed for qq possible

Production

Meson SpectroscopyMeson Spectroscopy

The New XYZ StatesThe New XYZ States

Discovery of ZDiscovery of Zcc±±(3900)(3900)

The experimental data set available is far from being complete. All strange hyperons and single charmed hyperons are energetically accessible in pp collisions at PANDA.

By comparing several reactionsinvolving different quark flavoursthe OZI rule and its possible violation, can be tested

In PANDA pp ΛΛ, ΛΞ, ΛΞ, ΞΞ , ΣΣ, ΩΩ, ΛcΛc, ΣcΣc, ΩcΩc

can be produced allowing the study of the dependences on spin observables.

QCD DynamicsQCD Dynamics

E. Tomasi-Gustafsson, M.P. Rekalo, PLB 504 (2001) 291

Generator:

|GM| = 22.5 (1 + q2 / 0.71)-2 (1 + q2 / 3.6)-1

= |GE|/|GM|

lower sensitivity @ higher q2

M. Sudol et al., EPJ A44 (2010) 373

p+pbar -> e+e- events p+pbar -> e+e- events generationgenerationL = 2 10 32 cm s → 2 fb-1 in 100 days

R=|GE|/|GM|

BaBAR

PS170PANDA sim

L = 2 10 32 cm s → 2 fb-1 in 100 days

M. Sudol et al., EPJ A44 (2010) 373

BABAR: B. Aubert et al. PRD 73 (2006) 012005

PS170: G. Bardin et al., NPB 411 (1994) 3

pQCD inspired: V. A. Matveev et al., LNC 7 (1973) 719 S. J. Brodsky et al., PRL 31 (1973) 1153

VDM: F. Iachello, PLB 43 (1973) 191

Extended VDM: E.L.Lomon, PRC 66 (2002) 045501

Individual determination of

|GE| and |GM| up to q2 14 (GeV/c)2 !!

PANDA Scenario: Expected PANDA Scenario: Expected Results Results

M. Sudol et al., EPJ A44 (2010) 373

L = 2 10 32 cm s → 2 fb-1 in 100 days

Absolute accessibleup to q2 28 (GeV/c)2

BABAR: B. Aubert et al. PRD 73 (2006) 012005E835: M. Andreotti et al., PLB 559 (2003) 20 M. Ambrogiani et al., PRD 60 (1999) 032002Fenice: A. Antonelli et al., NPB 517 (1998) 3PS170: G. Bardin et al., NPB 411 (1994) 3E760: T. A. Armstrong et al., PRD 56 (1997) 2509CLEO: T. K. Pedlar et al. , PRL 95 (2005) 261803DM1: B. Delcourt et al., PLB 86 (1979) 395DM2: D. Bisello et al., NPB 224 (1983) 379BES: M. Ablikim et al., PLB 630 (2005) 14

PANDA Scenario: Expected PANDA Scenario: Expected Results Results

E. Tomasi-Gustafsson, 12th International Conference on Nuclear Reaction Mechanisms, Villa Monastero, Varenna, Italy, 15 - 19 Jun 2009, pp.447, arXiv:0907.4442v1 [nucl-th]

L = 2 10 32 cm s → 2 fb-1 in 100 daysBABAR:

B. Aubert et al. PRD 73 (2006) 012005E835: M. Andreotti et al., PLB 559 (2003) 20 M. Ambrogiani et al., PRD 60 (1999) 032002Fenice: A. Antonelli et al., NPB 517 (1998) 3PS170: G. Bardin et al., NPB 411 (1994) 3E760: T. A. Armstrong et al., PRD 56 (1997) 2509CLEO: T. K. Pedlar et al. , PRL 95 (2005) 261803DM1: B. Delcourt et al., PLB 86 (1979) 395DM2: D. Bisello et al., NPB 224 (1983) 379BES: M. Ablikim et al., PLB 630 (2005) 14

Probing the Phragmèn-Lindelöf theorem:

PANDA Scenario: Asymptotic PANDA Scenario: Asymptotic BehavioursBehaviours

TMD: KTMD: KTT-dependent Parton Distributions-dependent Parton Distributions

Twist-2 PDFs )k,x(fkd)x(f T1T2

1

Distribution functions

Chirality

even odd

Twist-2

U

L

T

, h1,

Transversity

Boer-Mulders

Sivers

1hL1h

T1h

Tf1 Tg1

1f

1g

TMD PDF InvestigationTMD PDF Investigation

➠ Process SIDIS → convolution with FF

Drell-Yan → PDF only

pp annihilations: each valence quark can

contribute to the diagram

➠ Energies

@ FAIR unique energy range up to s~30 GeV2 with PANDA up to s~200 GeV2 with PAX

@ much higher energies → big contribution from sea-quarks

Drell-Yan ProcessDrell-Yan Process

• Drell-Yan: pp -> +-X

Collins-Soper frameCollins-Soper frame

Kinematics

x1,2 = mom fraction

of parton1,2

= x1 • x2 =

M2/s

xF = x1 - x2

Collins-Soper frame: Phys. Rev. D16 (1977) 2219.

SINGLE-POLARISED

UNPOLARISED

.

Drell-Yan Cross SectionDrell-Yan Cross Section

R.D. Tangerman and P.J. Mulders, Phys. Rev. D51, 3357-3372 (1995)

U = N(cos2φ>0)

D = N(cos2φ<0) DUDU

A

Asymmetry

CERN NA51 450 GeV/c

Fermilab E866 800

GeV/c

Di-Lepton ProductionDi-Lepton Production

pppp -> -> ll++ll--XX

A. Baldit et al., Phys. Lett. 332-B, 244 (1994)

R.S. Towell et al., Phys. Rev. D 64, 052002 (2001)

Phase space for Drell-Yan processesPhase space for Drell-Yan processes

x1,2 = mom fraction of parton1,2

= x1 • x2

xF = x1 - x2

= const: hyperbolaexF = const: diagonal

PAX @ HESR

symmetric HESR collider

1

1.5 GeV/c2 ≤ M ≤ 2.5 GeV/c2

PANDA

Drell-Yan Process and BackgroundDrell-Yan Process and Background

• Background studies: needed rejection factor of 107

• Drell-Yan: pp -> +-X

cross section 1 nb @ s = 30 GeV2

• Background: pp -> +-X, 2+2-X,……

cross section 20-30 b

m = 105 MeV/c2; m 145 MeV/c2

average primary pion pairs: 1.5

DY Asymmetries @ VertexDY Asymmetries @ VertexUNPOLARISED SINGLE-POLARISED

500KEv included in asymmetries

Acceptance

corrections crucial!

1 < qT < 2 GeV/c

2 < qT < 3 GeV/c

xP xP

xP

xP

xPxP

Physics Performance Report for PANDA arXiv:0903.3905

R = L·σ·ɛ

= 2·1032cm-2s-1 × x 0.8·10-33cm2× 0.33

= 0.05 s-1 ~ 130

Kev/month

Statistical errors for 500KEv generated

xP

)

)xP

xPPhysics Performance Report for PANDA arXiv:0903.3905

DY Asymmetries @ VertexDY Asymmetries @ Vertex

3 different systems contain double strangeness (S = -2)

Doubly strange hypernucleus:

Double hypernucleus:

Exotic hyperatom:

p

p

n

n

pp

n

n

p

e-

n pn Interactions: --nucleus: interplay between

the Coulomb and nuclear potential

Interactions: -N

Interactions:

From - hypernucleus to hypernucleus: after N

STORI’11 - F. Iazzi Politecnico di Torino&INFN

From hyperatom to - hypernucleus: absorption

Double Strange SystemsDouble Strange Systems

in the region close to the nucleus:

• Atomic orbitals overlap nucleus: Coulomb and Nuclear interaction shift the levels and broad them

• shift and width can be measured (only last level )

p

e-

np

n

-: M = 1.32132 [GeV/c2]; = 16.39.10-11 [s]; S = -2

• Stopped X- are captured into atomic (high) levels • X- undergoes an hyperatomic cascade• X-rays are emitted in the range 0÷1.2 MeV (12C) • Absorption from an atomic level into nucleus ends

the atomic cascade• Bohr radius in lowest levels(n=2,3): ≈ 15 – 25 [fm]

STORI’11 - F. Iazzi Politecnico di Torino&INFN

X-ray spectroscopy (from -) in the range: ≈ 0.1 – 1 [MeV]

No existing data!

Which Physics with Hyperatoms?Which Physics with Hyperatoms?

Physics (I): ΛΛ strong interaction (only possible in double hypernuclei)•Quarks: s-s interaction • YY potential: attractive/repulsive?

In One Boson Exchange mechanism: ΛΛ ΛΛ : only non strange, I =0 meson exchange (w,h...)• hyperfragments distribution: dependence on YY potential

Physics (II): ΛΛ weak interaction (only possible in double hypernuclei)Non Mesonic Hyperon Induced Decay:

• ΛΛ Λ n : (expected ΓΛn << Γfree ) (pΛ/N = 433 MeV/c)

• ΛΛ Σ-p : (expected ΓΣp << Γfree ) (pΣ/N = 321 MeV/c)

MeasurementsStrong interaction: • DBΛΛ(AZΛΛ) = BΛΛ(AZΛΛ ) - 2BΛ(A-1ZΛ) (from g spectroscopy)

Weak interaction: •momentum of p from decay•momentum of p from –p•momentum of – from , decay

p

p

n

n

STORI’11 - F. Iazzi Politecnico di Torino&INFNSeveral A data core of ΛΛ interaction

Formed by X- p ΛΛ reaction inside nucleus

Which Physics with Which Physics with ΛΛΛΛ Hypernuclei?Hypernuclei?

B

B.E.

A

The PANDA DetectorThe PANDA Detector

STT Detectors

Physics Performance Report for PANDA arXiv:0903.3905

The PANDA DetectorThe PANDA Detector

STT Detectors

Physics Performance Report for PANDA arXiv:0903.3905

Detector requirements:

• nearly 4 solid angle (partial wave analysis)

• high rate capability (2·107 annihilations/s)

• good PID (, e, , , K, p)

• momentum resolution (~1%)

• vertex info for D, K0S, (cτ =123 m for D0, p/m ≈

2)

• efficient trigger (e, , K, D, )

• no hardware trigger (raw data rate ~ TB/s)

The Micro-Vertex The Micro-Vertex DetectorDetector

FAIRNESS2012, L. Zotti

The Micro-Vertex The Micro-Vertex DetectorDetector

FAIRNESS2012, L. Zotti

Tracking DetectorsTracking Detectors

I. Lehmann, Spin-Praha 2012

Cherenkov DetectorsCherenkov Detectors

I. Lehmann, Spin-Praha 2012

Electromagnetic Electromagnetic CalorimetersCalorimeters

I. Lehmann, Spin-Praha 2012

MDT layoutMDT cross section

Muon Detector SystemMuon Detector System

Iarocci Tubes working in proportional mode

Ar+CO2 gas mixture

Prototype readyFE electronics in production

TDR for the PANDA Muon System, 2nd Draft (May 2011)

JINR - Dubna

Muon Detector Muon Detector LayoutLayout MDT’s Wires Strips

Barrel 2133 17064 49916

End Cap 618 4944 8911

Muon Filter 424 3392 6876

Forward Range System 576 4608 7128

Total 3751 30008 72831

Range System Range System PrototypePrototype

JINR - Dubna

DIRCDIRCMVDMVD

EMCEMC

Physics Performance Report for PANDA arXiv:0903.3905

STTSTT

PANDA PID Requirements:

particle identification essential for PANDA momentum range 200 MeV/c – 10 GeV/c Extreme high rates 2·107 Hz good particle separation (K-e)

different detectors needed for PID

Particle Particle IdentificationIdentification

All the details of the PANDA experimental program are reported in the “Physics Performance Report”.

Within this document, we present the results of detailed simulations performed to evaluate detector performance on many benchmark channels.

arXiv:0903.3905v1

PANDA Phyisics PANDA Phyisics Performance ReportPerformance Report

SummarySummary

PANDA physics program

unique program accessible with antiproton beams

addresses key questions

high discovery potential

high statistics and high precision results

Beginning in 2018