foreign national contribution to jlab science

Patrizia Rossi Jefferson Lab User Meeting - June 4-6, 2012 1

Foreign National Contribution to JLab Science….an Incomplete Overview

Total Foreign Users ~ 400 from 30 Countries1


JLab science: the 6 GeV & the 12 GeV era Structure of the Hadrons

• New view of nucleon via the GPDs & TMDs• EM Form Factors• N* and transition Form Factors

Dynamics of the nucleons in the nuclei • The Quark Structure of Nuclei (resolving the EMC effect)• The Short-Range Behavior of the N-N Interaction and its QCD Basis• Cold nuclear matter

Electroweak Interaction• High Precision Tests of the Standard Model at low energies via PV-DIS• Measure nuclear properties using the weak interaction

Origin of quark and gluon confinement • Gluonic excitations - existence and properties of exotic mesons


Generalized Parton Distributions form factors

location of partons in nucleonTransverse charge & current densities

parton distributionsQuark longitudinal momentum fraction x

& helicity distributions

GPD(x,x,t)

x+x x-x

p p’

t

longitudinal momentum fraction x at transverse location b T

Patrizia Rossi Jefferson Lab User Meeting - June 4-6, 2012

Accessing GPDs

Deeply Virtual Compton Scattering

Deeply Virtual Meson Production

Difficult to extract GPDs from the data

Quantum number of final state selects different GPDs: • VM (r, w, f): H E• PS mesons (p, h): H E • DVCS (g): H, E, H, E

~ ~

~ ~

(DVMP)(DVCS)

GPDs extraction possible ONLY through models/parameterizations

Physical observables involve convolution of GPDs - only x and t accessible exp.

GPDs are more complicated than PDFs - functions of 3 variables instead of 1

Exclusive reactions are smaller and harder to measure than inclusive ones

4

DVCS: different observables have different sensitivity to the 4 GPDs


The French Collaboration @ Jlab

CEA/Irfu and CNRS/IN2P3 have participated in the scientific activity at Jefferson Lab since 1991

The French Collaboration was initially contributing to the 6 GeV program in Hall A, Hall B and Hall C

Presently, the French Collaboration concentrates its activities in Hall A and Hall B with a significant role and participation in the current 6 GeV program and in the 12 GeV Upgrade.

Plays a Key role in the GPD program


From data ……C. Munoz et al., PRL 97, 262002 (2006) (Hall-A)M. Mazouz et al., PRL 99, (2007) 242501BSA: F.X Girod et al., PRL 100, 162002 (2008)TSA: S. Chen et al., PRL 97, 072002 (2006)

Hall A

Evidence of twist-2 dominance in the DVCS-BH interference description

Significant amount of data on BSA accumulated and consistent with GPDs based predictions

Hall B


……to GPDs

M. Guidal, PLB 689, 156 (2010) , H. Moutarde PRD 79, 094021 (2009)

• DVCS: 4 indipendent GPDs each depending on 3 variable• DVCS amplitudes decomposed into R and I parts 8 GPDs related quantities (CFFs)• G-fitter: model-indipendent fitting procedure to extract the 8 CFFs using VGG

Fitter codes developed in France

Patrizia Rossi Jefferson Lab User Meeting - June 4-6, 2012

Hall A

Hall A/B DVCS – 6 GeV

Spectro e’

LiquidH2, D2

e

g

calorimeter

cryostat

HALLA

HALLB

8


n DVCS @ 12 GeVneeded for flavour separation gives access to GPD E through ALU

Quark angular momentum (Ji’s sum rule)

k

k’q’

GPDsn n’

DVCS on the neutron – 11 GeV

DsLU/s

f= 60°xB = 0.17Q2 = 2 GeV2

t = -0.4 GeV2

Ju=.3, Jd=.1Ju=.1, Jd=.1Ju=.5, Jd=.1Ju=.3, Jd=.3Ju=.3, Jd=-.1

VGG Model(calculations by M. Guidal)

E12-11-003S. Niccolai et al.

Central Neutron Detector (CND)

CLAS12


The Italian Collaboration @ JLabINFN is participating to the scientific activity at Jefferson Lab since 1991

Presently, it includes 80 scientists among experimentalists (~50) and theorists (~30) from 16 INFN Units and National Lab., participating to the 12 GeV Upgrade in Hall A and Hall B

The collaboration was initially formed by ~25 scientists and has been contributing to the 6 GeV program in Hall A and Hall B


Scientific Activity at 6 GeV & 12 GeV

Hadron Spectroscopy:• Study of the Nucleon Excitation Spectrum and Search for Missing Resonances• Study of the Meson Spectrum• Search for Exotics

The Structure of the Nucleon:• Nucleon Form Factors• Nucleon Structure Functions from Inclusive and Semi-Inclusive Processes• Study of the Spin Structure of the Nucleon

The Study of the Transition between Hadronic and Partonic Degrees of Freedom:• Vector Meson Production at Large Momentum Transfer• Deuteron Photodisintegration

The Nuclear Structure:• The Neutron Skin of 208Pb• Hypernuclear Spectroscopy• Study of N-N Correlations

The scientific activity of the Italian Groups is subdivided into 4 main fields that belong to the science mainstreams of the Jefferson Lab physics program


Experimental Equipment for Hall A & Hall B – 6 GeVCerenkov Counter for low-Q2

Polarized Target for electron beam

Large Angle Calorimeter for detect. of neutrals

septum magnets

RICH Detector

Gas Cherenkov

Total Investment: ~ 9M$


Measurements of Nucleon FF at high Q2

E-12-07-109

Test different models (including # contributions from the quark OAM)

Investigate the transition region (perturbative / non perturbative)

(E-12-07-109, E-12-09-016, E-12-09-019)

High Luminosity (~1039) Forward angle (down to 7 degree)Equipment flexibility

SBS

Italian responsibility on the primary tracker:Large area GEM chambers for tracking with resolution ~70 mm + small silicon planes Development of the electronics for more than 100000 channels


Transverse Momentum Distributions

transversity pretzelosity

U

L

T

U L T

f1

g1L

g1T

h1

Th1L

T

f1T

T

h1 h1T

T

,

helicity

worm-gear

nucl

eon

pola

rizat

ion

quark polarization

Boer-Mulders

worm-gear

Sivers

• DIS → DS 0.25

• RHIC + DIS → DG« 1

• → Lq

The Incomplete Nucleon


The 12 GeV TMD program

Italian co-spokesperson in all 12 GeV TMDs proposals with Unp. Long. and Trans. Polarized Targets Target cell

In-beam cryostat

A U

T

HD- Ice target: INFN contribution

• dilution refrigerator• Raman analysis of HD gas• NMR for polarization

monitoring

e-

Aerogel

Mirrors

MA-PMTs

Proposed RICH det. for K identification with CLAS12

INFN (project coord.), Glasgow U., Chile, USA

PR12-11-111M. Contalbrigo et al.


Search for Exotics

Quarks Excited Flux Tube

Hybrid MesonS 0L 0

J PC 0

J PC 1

1

J PC

1

1

p, Klike

J PC 0 1 2

0 1 2

S 1L 0

J PC 1

J PC 1

1

like g,r

Exotic

Flux tube excitation (and parallel quark spins) lead to exotic JPC

16

Quantum Numbers of Hybrid Mesons


Search for Exotics in Hall B

Edinburgh U., Glasgow U., INFN (project coordination), JLab, NSU, Orsay, Saclay

E12-11-005:Meson Spectroscopy with low Q2 electron scattering in CLAS12 M. Battaglieri et al.


GlueX in Hall D: Canadian contribution

Completion of 48 Barrel Calorimeter (BCAL) • Characterization of large-array Hamamatsu SiPMs• Mini BCAL beam tests in Hall B • Cosmics with SiPMs on full-length module• Fine-grained geometry simulation of sampling fraction as look-up tables

for HDGEANT (sim & reconstruction)

Big Investment: ~ 8M$


N* Program: Russian Contribution

First extraction of transition form factors for P11(1440), D13(1520) states from the CLAS p(e,e’ppp-) data using JLAB-Mosc. State University (JM) model.

I. G. Aznauryan et al., CLAS Collaboration,Phys. Rev. C 80, 055203 (2009). V.I.Mokeev eta al., CLAS Collaboration, arXiv:1205.3948 [nucl-ex].

ppp 2012

ppp 2010

Np2009

P11(1440)A1/2

Quark models:I. Aznauryan LC

Relativistic covariant app. by G.Ramalho /F.Gross EBAC-DCC MB dressing

S. Capstick LC

The electrocouplings are consistent with P11(1440) structure as a combined contribution of: a) quark core as a first radial excitation of the nucleon as a 3-quark ground state, and b) meson-baryon dressing.


Armenia• More than 20 years of successfully collaboration in all three experimental Halls • Some of highlights ANSL groups’ contributions to the instrumentation are:

– Hall-A: 702 channel lead-glass calorimeter for RCS, neutron detector for GEN, pre-shower counters for HRS

– Hall-B: development of the electromagnetic calorimeters, development of experimental control systems (slow controls)

– Hall-C: lead-glass calorimeter for HMS and SOS, aerogel Cherenkov detector for HMS

Hall-B calorimeter readout system

Hall-A LG calorimeter


NN short range correlations in nuclei

K.S. Egiyan et alPRL 96, 082501 (2006)

• Two separate plateaus:1.5 < xB < 2

xB > 2.25 as predicted by models that include 2- and 3-nucleon SRC

• The per-nucleon probabilities of 3-nucleon SRC (relative to A=3) are 2.3, 3.2, and 4.6 times larger for A = 4, 12 and 56.

Cross section ratios of 4He, 12C, and 56Fe to 3He @ 1 < xB < 3

first measurement of 3-nucleon SRC probabilities in nuclei


The role of Japan in the Hypernuclear physics• Hypernuclei are bound states of nucleons with a strange baryon (L hyperon)• L-N vs N-N force will provide clues to the QCD description of the N-N interaction

• HKS spectrometer (QQD)• HES spectrometer (QQD)• Detectors and Electronics• Splitter Magnet

Total: ~ 5M$

HES HKS

SLITTER

HALL C•In a decade, a wide variety of hypernuclei, 7

ΛHe, 9ΛLi, 10

ΛBe, 12ΛBe,

16ΛN, 28

ΛAl and 52ΛV, have been

studied by the (e,e’K+) reaction.

•High energy resolution and precision measurements make these experiments unique and crucial tools for this field.

• High accuracy determination of the Λ binding energy for different hypernuclei has been achieved

•The Japanese group remain enthusiastic and are trying to develop a coherent plan to present to the PAC


Chinese Collaboration on the Solid ProjectGEM detectors• Five groups actively work on R&D,

prototyping and plan to take full responsibility for the whole package

• Already 2 (chinese) grants for R&D and prototyping

• Plan to seek major funding next year from NSFC/MOST, support from CAS

MRPC detector• Tsinghua U. • Experience from building MRPC for STAR at RHIC.

The Chinese collaboration will probably double in the next few years: 11 groups (institutions) are joining each having on average 3-5 active members


Chinese Collaboration on the Solid Project

SOLID: e3He →ep+/-X

6 GeV data

• 3 approved high-impact (A rated) experiments + 1 conditionally approved (Two Chinese physicist co-spokespersons )

2 (+1) Semi-inclusive DIS: transverse spin/transverse momentum distributions1 Parity-violating DIS: low-energy test of the Standard Model

• Several theory groups active on the topics

AUT


Conclusions & Outlook

Jefferson Lab as a unique world-leading facility for nuclear physics research has attracted since the beginning an international community which has played a major role in the scientific program

The 12 GeV upgrade has reinforced the interest of the international community due to:

- New vistas in QCD- Growing program Beyond the Standard Model- Capability to be on schedule

The Countries of France, Italy, UK have being funded since several years by the European Community (EU) to develop R&D and analysis network for the physics at JLab


Conclusions & OutlookThe impact of JLab science in the international panorama can be improved:

Establishing collaborations with other facilities having similar/complementary physics programPanda @ FAIR (in progress)

LNF/ INFN……..

LNF: Search for new forces mediated by vector boson A’

Organizing workshop/conferences with HEP communityTests of the standard model at Jlab complementary to the information obtained at LHC

TMD results foundamental for RICH/LHC physics Organizing Jlab Collaborations Meetings outside USANational Funding Agencies are usually invited to attendFor the last 5 years this has been done regularly by the Hall B Collaboration (every 2 years) but never by Hall A, Hall C and only once by Hall D

foreign national contribution to jlab science

Documents

different gpds

indipendent gpds

convolution of gpds

hall c

hall ahall ab dvcs

gev program

hall aevidence of twist

h e dvcs g