Antiprotons physics with · 2014. 6. 13. · • Injection of pbar at 3.7 GeV • Slow synchrotron...

Egle Tomasi-Gustafsson

(on behalf of the Panda Collaboration) IRFU, SPhN-Saclay,

and

IN2P3 - IPN Orsay France


Anti-Proton

ANnihilation at

DArmstadt

@

Antiprotons physics with

Suzdal, 4-VI-2014 1

Quarks - 2014, Suzdal, Russia, 2-8 June


• How are color neutral

objects formed?

• Confinement: why free quarks are not observed?

• Origin of the hadron mass: the Higgs mechanism accounts for some percent of the hadron mass

• Establish existence and

properties of exotics, hybrids, glueballs

• Structure of the nucleon (charge, magnetic, spin distributions)

Suzdal, 4-VI-2014 2

Open questions in QCD (some..)


• From high intermediate energy complexity

Suzdal, 4-VI-2014 3

Hadron Physics

Quark model (Gell-Mann 1964) Hadrons are formed by quarks

which interact via gluons Baryons are hadrons formed by

3 quarks Mesons are hadrons formed by

quark-antiquark

Hadrons consist of bound systems of non-relativistic heavy constituents, coupling is small: non perturbative effects or higher order corrections can be neglected

10-15 10-17

0.2

0.8

PANDA (Antiproton

Anihilation at Darmstadt) :

hadron physics

Egle Tomasi-Gustafsson Suzdal, 4-VI-2014

About 3000 scientists from around the world will carry out experiments to understand the fundamental structure of matter, to explore exotic forms of it and to find answers of how the universe evolved from its primordial state into what we see today. FAIR covering four major fields: allows to carry out several physics programs in parallel:

APPA Physics - Atomic, Plasma Physics and Applications

CBM - Compressed Baryonic Matter

NUSTAR Physics – Nuclear Structure,

Astrophysics and Reactions

http://www.fair-center.de

4


• Introduction • The antiproton probe

• Conclusions

• The PANDA detector • The experimental programme

• Hadron spectroscopy Charmonium spectroscopy Open charm Gluonic excitations

• Interaction of hadrons Hypernuclear Physics In medium modification of mesons Color transparency

• Hadron structure TDA, GDA, Drell Yan, Electromagnetic Proton Form Factors

Suzdal, 4-VI-2014

arXiv:0903.3905v1

5

Plan


• First accelerated at LEAR (1983) • 2-3 109 pbar per hour • Momentum range 100 MeV/c -2 GeV/c

• p/p≤ 0.8x10-3

• Polarized antiprotons at Fermilab

• Parity-violating (in flight) decay of anti-L0 hyperons P=45%, I(p)~ 104 s-1 (physics!) • Stern-Gerlach separation in inhomogeneous

magnetic field (too expensive) • Elastic scattering on C, LH2…

• and also channelling, penning traps, stochastic techniques, dynamic nuclear polarization

Suzdal, 4-VI-2014 6

Antiprotons

• Discovery of antiproton (Segré, Chamberlain,1955)


GSI – PAX

Unpolarized p beam

Polarized H target

Polarized p beam

F. Rathmann (Juelich)

Suzdal, 4-VI-2014 7


HESR

SIS 100/300

SIS18

RESR/CR

30 GeV Protons

50 MeV p-Linac

Cu Target

107 p/s @ 3 GeV

Collecting

Accumulating

Precooling

Accelerating

Cooling

100m

PANDA

pbar production •proton Linac 50 MeV •accelerate p in SIS18/SIS100 •produce pbar on target •collect pbar in CR, •cooling in RESR

http://www-panda.gsi.de/ http://www.fair-center.eu/

Parameters of HESR • Injection of pbar at 3.7 GeV • Slow synchrotron (1.5-14.5 GeV/c) • Storage ring for internal target operation • Luminosity up to L~ 2x1032 cm-2s-1

• Beam cooling (stochastic & electron) 8

Antiprotons at FAIR

Suzdal, 4-VI-2014

p

• Dedicated experiments in the past decades for

– Hadron spectroscopy

– Hadron structure

– Interaction of Hadrons


need of • Highest Rates • Good Resolution • Good Particle Identification

Fixed target experiment

and

Internal experiment

in HESR storage ring

(not interacting antiprotons

recirculate)

detector

Suzdal, 4-VI-2014 9

Hadron Physics with Antiprotons

Accelerator and Detector

are built and optimized together

for the best performances

• 4p acceptance • high rate capability (average

interaction rate 20 MHz) • excellent tracking capabilities,

momentum resolution 1% • Vertex reonstruction for D, Ks ,

hyperons • good PID ( e, m, p, K, p )

Čerenkov, ToF, dE/dx

• g detection 3 MeV- 10 GeV PWO crystal calorimeter

• flexible and modular design • continuous data acquisition, no hardware trigger, intelligent software trigger

Detector requirements

QCD bound states Hadrons in nuclear matter Electroweak physics Electromagnetic processes Hypernuclear Physics

Physic topics

Suzdal, 4-VI-2014 Egle Tomasi-Gustafsson 10

p

detector

G.Boca GSI, Germany & U. Pavia, Italy

Solenoid Magnet (2T)

Dipole Magnet (1T)

Target System

Micro Vertex Detector

Straw Central Tracker

GEM Detectors

Straw Chambers

SciTil

Target System and Tracking Devices


p

detector


Disc DIRC Forward RICH

Forward ToF

Muon Detection

Barrel DIRC

Particle ID detectors


PWO Barrel EMC Forward EM Calorimeter

PWO Fwd Endcap

PWO Backward Endcap


detector Calorimetry



• Hadron spectroscopy

Charmonium spectroscopy Open charm Gluonic excitations

Suzdal, 4-VI-2014 14

Experimental Program

Egle Tomasi-Gustafsson Suzdal, 4-VI-2014 15

Recent findings at B-factories: X,Y,Z

Search for glueballs,hybrids…


Dalitz Plot

700000 events f0(1500)

M=1505±23 MeV

Γ=111±12 MeV

The lightest glueball? - No « flavor blind » decay - Mixing?

JPC = 0++

High statistics needed!

Suzdal, 4-VI-2014

•The resonance decays into two pseudoscalars:0+0-0- •The third pseudoscalar removes the excess energy

000ppppp

Crystal Barrel (LEAR)

05ppp

0'ppp0ppp

0p

LLKKpp

16

Lightest glueball: a scalar with JPC = 0++


Hadron spectroscopy at PANDA

JPC = 0--,0+-, 1-+, 2+-, 3-+

• hybrids

Gluon 1– (TM) 1+(TE)

1S0, 0–+ 1++ 1––

3S1, 1–– 0+- 0–+

1+- 1–+

2+- 2–+


Resonance production

JPC = 1- -

J = 0,2,.. C = +

J = 1,.. C = -

Formation: -> (precision physics)


e+e− →ψ '→γχ1,2 →γ (γ J /ψ )→γγ e+e− Invariant mass reconstruction → detector resolution ≈ 10 MeV (radiative decay)

pp→χ1,2 →γ J /ψ →γ e+e− resonance scan: the precision depends on the beam resolution. • gluon-rich environment

• all qq allowed quantum numbers

• q-qbar annihilate into gluons


Appearance of a resonance in production mode and disappearance in formation mode sign its exotic nature

Very precise scan of a resonance in formation mode: depends on HESR beam momentum resolution p/p~10-5

Search for glueballs,hybrids…

Suzdal, 4-VI-2014

Mass resolution e+e- : 10 MeV FermiLab 240 keV HESR 30 keV

19

Egle Tomasi-

Gustafsson

About pp cross sections

PANDA

Crystal Barrel E760/E835

Obelix

PS185

Jetset

[mb]


Source: PDG

pp cross sections

•Cross sections expectations for – glueballs and light hybrids

• rates comparable to light hadrons

– charmed hybrids and molecules

• rates comparable to charmed hadrons

100 mb

10 mb

1 mb

100 μb

10 μb

1 μb

100 nb

10 nb

1 nb

ηc

χc0

χc2

ηcπ0

Hybrids

Glueballs

X(3872)

Suzdal, 4-VI-2014

21 Egle Tomasi-Gustafsson

[mb]

[nb]

[mb]


Panda will have: - Better luminosity - Better beam momentum resolution - Better detector (coverage, PID,magnetic field..)

Suzdal, 4-VI-2014

Antiproton facilities

22

(Low energy beams)

The detector

Interaction of hadrons

Hypernuclear Physics In medium modification of mesons Color transparency





U. Wiedner

Hypernuclei: replacing u or d with s-quark 3rd dimension: strangeness

35 L-hypernuclei, few LL-hypernuclei known no antihyperons in nuclei observed search for H-dibaryon: uuddss

New approach: Capture and conversion: 5-10% Double mesonic decay: 10% Data taking efficiency: 50% Several tens of LL-hypernuclei/day expected

•Hyperon is not limited by the Pauli principle •Baryon-baryon interactions: *L−N interaction: short L lifetime * L-L scattering : exp. Impossible

•Shell model parameters •Weak decays: LN ->NN, LL->NN

25 Suzdal, 4-VI-2014 Egle Tomasi-Gustafsson

Double Hypernuclei

capture

of Ξ- in

secondary

target:

atomic

transition


• Hadron structure

Electromagnetic Form Factors TDA, GDA,Drell Yan




_ _

q20

e-

e+ p

p

q2 q2=4mp2

Time-Like

FFs are complex Space-like

FFs are real Un

ph

ysic

al

reg

ion

GE=GM

GE(0)=1

GM(0)=mp

Asymptotics

- QCD

- analyticity

p+p ↔ e++e- e+p e+p

p+

p ↔

e++

e- +

p0


Hadron Electromagnetic Form factors )2q(

2F

M2

qi)2q(

1F

m

mgm

Egle Tomasi-Gustafsson 28

The polarization induces a term in the cross section proportional to GE GM

Polarized beam and target or

polarized beam and recoil proton polarization Suzdal, 4-VI-2014

The polarization method (theory:1967)


The simultaneous measurement of Pt and Pl reduces the systematic errors

Suzdal, 4-VI-2014

C. Perdrisat et al, JLab-GEp

collaboration

The polarization method (exp: 2000)

A.I. Akhiezer and M.P. Rekalo, 1967

Jlab-GEp collaboration 1) "standard" dipole function

for the nucleon magnetic FFs GMp and GMn

2) linear deviation from the dipole function for the electric proton FF Gep

3) QCD scaling not reached

3) Zero crossing of Gep?

4) contradiction between polarized and unpolarized measurements

Suzdal, 4-VI-2014 30 Egle Tomasi-Gustafsson

A.J.R. Puckett et al, PRL (2010), PRC (2012)

Polarization experiments


•Some models (IJL 73, Di-quark, soliton..) predicted such behavior before the data appeared

• Simultaneous description of the four nucleon form factors...

• ...in the space-like and in the time-like regions

• Consequences for the light ions description

• When pQCD starts to apply?

• Source of the discrepancy

BUT

Suzdal, 4-VI-2014

Issues

Time-like observables: | GE| 2 and | GM| 2 .


As in SL region: - Dependence on q2 contained in FFs - Even dependence on cos2q (1g exchange) - No dependence on sign of FFs - Enhancement of magnetic term but TL form factors are complex!

A. Zichichi, S. M. Berman, N. Cabibbo, R. Gatto, Il Nuovo Cimento XXIV, 170 (1962)

B. Bilenkii, C. Giunti, V. Wataghin, Z. Phys. C 59, 475 (1993).

G. Gakh, E.T-G., Nucl. Phys. A761,120 (2005).


arXiv:0810.4245 DAPNIA-04-10

Individual determination of |GE| and |GM|

pQCD

VMD

F. Iachello et al., Phys. Rev. C 69 (2004) 055204

E. L. Lomon, Phys. Rev. C 66 (2002) 045501 V. A. Matveev, S. J. Brodsky , D. V. Shirkov….

E. A. Kuraev et al., Phys. Lett. B 712, (2012)


Panda Simulations

A. Dbeyssi PhD


Proton form factors at large q2

E. T-G. and M. P. Rekalo, Phys. Lett. B 504, 291 (2001)


L = 2 10 32 cm-2 s-1 100 days

Applies to NN and NN Interaction (Pomeranchuk theorem) t=0 : not a QCD regime!

Connection with QCD asymptotics?

Phragmèn-Lindelöf theorem

Analyticity

Panda

Efficiency extrapolation

• Experimental statistical error ~ 1/ V e


V e e

Hadronic background

Channels with more than two charged particles in the final state can be rejected using the kinematics (missing mass)

5.4 8.2 13.9

>99% >99% >99.9%

>5% >5% >6%

N of fired crystals

in the EMC

>5 >5 >5

[178°-182°] [178°-182°] [175°-185°]

[178°-182°] [178°-182°] [175°-185°]

Invariant mass [GeV] No cut > 2.14 GeV > 2.5 GeV

Background [Events] 0 0 0


Starting from 107 events:


Most probable in the mb region : - Five pion production - Charge exchange

A.Dbeyssi amd ETG, Panda-note AD-12-12-13

About cross sections…


At rest

p=5 GeV/c

p=10 GeV/c

Five pions are preferentially created in annihilation at rest

• Quark-gluon dynamics (similar to quark-gluon plasma)

• Statistical models • Quasi-two-body dorway

states • ……

Role of the different contribution to the NN potential (dynamical selection rules)

Exclusive final states


April 2014: FAIR employees planted

10000 trees for forest conversion

Stabilizing the ground

On-line web camera

GSI today


Conclusions

• FAIR will provide antiproton and ion beams with unprecedented intensity and quality.

• In the final construction FAIR consists of eight ring colliders with up to 1,100 meters in circumference, two linear accelerators and ~3.5 kilometers beam control tubes.

• Timeline • Construction MOU in preparation • Start construction • Preassembly in Juelich in 2016/17 • Mounting at FAIR in 2017/18 • Commissioning end 2018

• Major advances in different fields of physics are expected!

Suzdal, 4-VI-2014 Egle Tomasi-Gustafsson

Thank you for attention!

42

благодарю за внимание


• Almost 600,000 cubic metres of concrete • Over 35,000 tonnes of steel • 500,000 tonnes of other construction material will be used

to build FAIR. • Over one million cubic metres of soil will be excavated

during construction and used at a later stage to cover underground structures.

• Work on the foundations is set to start shortly. This will involve embedding around 1,500 piles, with diameters of 1.2 metres, up to 65 metres into the ground to create a suitable foundation for the buildings.

• During the most intensive construction periods, up to 600 construction workers, technicians and engineers will be working at the site.

More numbers


Suzdal, 4-VI-2014

44

Crossing Symmetry

Scattering and annihilation

channels:

- Described by the same amplitude :

- function of two kinematical variables, s and t

k2 → – k2

- which scan different kinematical regions

p2 → – p2

GPD,GDA,TDA….(x,x,t)


0p

- eepp

0/ p Jpp

45

ggpp


Open charm

The quark model was expected to describe well the excited states of Ds (cs)

Two new states 0+ and 1+

do not fit the potential predictions

46


More excited states were discovered... quantum numbers were assigned

… by studying DK,D*K distributions 47

Open charm

The detector



Models in T.L. Region (polarization)

VDM : IJL

Ext. VDM

‘QCD inspired’

R

Ay Axx Ayy

Axz

Azz

E. T-G., F. Lacroix, C. Duterte, G.I. Gakh, EPJA 24, 419(2005)

X(3872)


New state discovered by Belle in

e+e-Y(4S)BB; BK X X (J/ y p+p-), J/y µ+µ- or e+e-

M = 3872.0 0.6 0.5 MeV

2.3 MeV (90 % C.L.)

X(3872) seen also by CDF

ppX+all; X D0 D*0 (p0),

M = 3871.4 0.7 0.4 MeV

PRL 91, 262001 (2003)

Seen also by

51

Narrow width


X(3872) highlights

X(3872) J/ y p+p- M = 3871.57 0.25 MeV M(D0 D*0 )= 3871.94 0.33 MeV

X 2.3 MeV (90 % C.L.)

Very close to DD* threshold

p+p- invariant mass (Belle 03) X(3872)J/y g- (Belle 05) C-parity =+

p+p- angular distr. (Belle 05) (CDF 06) J

PC = 1+(?)

X0,+ J/ yr0,+ (Babar 05) I=0

Br[X J/ y p+p- p0] Br[X J/ y p+p-] =

1.0±0.4 ±0.3 (Belle 05)

0.8±0.3 (Babar 10)

I=0

I=1

Large Isospin

violation

52


Time-Like Electromagnetic Form Factors

Antiparticles, antihadrons, antimatter


• The relativistic equation for e- has a second solution with the same mass but opposite sign (e+)

(Dirac, 1930) • Discovery of the positron (Anderson, 1933)

(cosmic rays)

• Generalization to the strong interaction, invariance by C-parity (Wick, 1958)

Suzdal, 4-VI-2014

• CPT invariance (Lee, 1957) • Discovery of antiproton,

(Segré, Chamberlain,1955) • Discovery of antineutron

(Cork, 1956) • Discovery of antideuteron

(Zichichi, 1965)

54

d = 150 mm

d = 20 mm

p

by cortesy of D. Rodriguez

Dedicated beam pipe

Backward End Cap Calorimeter and MVD will be not used

Modular structure HPGe encapsulated crystal attached to the X-Cooler

Modular design

55 Suzdal, 4-VI-2014 Egle Tomasi-Gustafsson

Unité mixte de recherche

CNRS-IN2P3

Université Paris-Sud 11

91406 Orsay cedex

Tél. : +33 1 69 15 73 40

Fax : +33 1 69 15 64 70

http://ipnweb.in2p3.fr

PANDA IPNO –R&D Détecteurs Department – septembre 2012

Prototype

120 PbWO4 II crystals operated at

-25°± 0.2°

g (3 MeV-10 GeV) and e detection

• Fully designed at IPN Orsay

• Under construction

• To be tested with cosmics and

photon beam (2012/13)

Barrel Calorimeter

• 11000 PWO type II Crystals

• Large Area Avalanche Photodiodes

(APD) readout, (2) 7x 14 mm2

• σ(E)/E1.%/√E + const (


The Rosenbluth separation

)2(2)2(2

)1(

1Q

MGQ

EG

Mottd

d

d

d

e

2M4

2Q

,

1

2

e2)tan1(21

-

qe

2M

G2E

GR

e

Holds for 1g exchange only

Linearity of the reduced cross section

PRL 94, 142301 (2005)

tan2qe dependence e

Q2 f

ixed

Suzdal, 4-VI-2014


Proton Form Factors ...before

Rosenbluth separation/ Polarization observables

Dipole approximation: GD=(1+Q2/0.71 GeV2)-2

Suzdal, 4-VI-2014

Egle Tomasi-

Gustafsson

S1

S2

S=S1+S2

J=L+S

P=(-1)L+1

C=(-1)L+S

L

Exotic Quantum Numbers with Simple Hybrids

Gluon 1– (TM) 1+(TE)

1S0, 0–+ 1++ 1––

3S1, 1–– 0+- 0–+

1+- 1–+

2+- 2–+

JPC exotic impossible for qq

JPC = 0--,0+-, 1-+, 2+-, 3-+

• hybrids

Production -> All possible quantum numbers Discovery potential!


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Antiprotons physics with · 2014. 6. 13. · • Injection of pbar at 3.7 GeV • Slow synchrotron...

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