18 Set 2008 JLab12.0

JLab12 / Gruppo Roma1-ISS

JLab12

Prima Riunione Plenaria

18 Settembre 2008

18 Set 2008 JLab12.0

Chi Siamo• Evaristo Cisbani (ISS) 70• Francesco Cusanno (ISS) 100• Salvatore Frullani (ISS) 40• Francesco Ghio (ISS) 20• Franco Garibaldi (ISS) 70• Franco Meddi (UniRoma1) 30• Giudo Maria Urciuoli (INFN-RM1) 30

Totale 3.6 FTE

Tecnici (da ISS)• Stefano Colilli 40• Rolando Fratoni70• Fausto Giuliani 80• Massimo Gricia 70• Maurizio Lucentini 40• Fabio Santavenere 80

Totale 3.8 FTE

18 Set 2008 JLab12.0

Apparati Realizzatihadron arm

electron arm

septum magnets

RICH Detector

18 Set 2008 JLab12.0

E – 91-111 S. Frullani, J. Kelly, A. Sarty“Investigation of N- transition via polarization observables in Hall A”

E – 94-107 F. Garibaldi S. Frullani, J. LeRose, P. Markowitz“High Resolution Hypernuclear 1p shel Spectroscopy”

E – 98-108 O.Baker,S. Frullani, M. Iodice“Electroproduction of Kaons up to Q2 = 3 GeV/c)2”

E – 97-110, JP Chen, A Deur, F. Garibaldi“*GDH Rum Rule of 3He and Neutron using nearly real photons”

E 06-007, K. Aniol, A. Saha, G.M. Urciuoli, G. Udias,“Impulse Approssimation Limitations to the (e,e’p) on 208Pb(e,e’p)”

Esperimenti in Hall A con leadership italiana

6 GeV ran

18 Set 2008 JLab12.0

E – 06-011, E. Cisbani, H. Gao, X, Jiang“Target Single Spin Asymmetry in Seminclusive Deep Inelastic (e’e’ pai+)

Reaction on a Transversity Polarized 3He Target”

E – 06-002, R. Michaels, P. Souder, G.M.Urciuoli“A Clean Measurement of Neutron Skin of 208Pb trough Parity Violatung

Electron Scattering”

E – 07-012, F. Garibaldi, M. Iodice, J. LeRose, P. Markowitz“The Angular Dependence of 16O(e,e’K)16N_Lambda, and H(e,e’K)Lambda”

12 GeVPR-12-07-109, C.Perdrisat, L.Pentchev, E.Cisbani, V.Punjabi, B.Wojtsekhowski“Large Acceptance Proton Form Factor Ratio Measurement at 13 and 15

GeV2 Using Recoil Polarization Method”

6 GeV to run

- working groups ---> white papers- hypernuclear physics- spin structure of neutron- form factors

- Gep --> super bigbit spectrometer for Hall A

18 Set 2008 JLab12.0

Proton E/M Form Factors(by polarization transfer in elastic ep scattering)

2tan

2

)( e

p

ebeam

l

t

Mp

Ep

M

EE

P

P

G

G

Longitudinal Pl and transverse Pt polarizations of the scattered proton

22MpEp GG

d

d

Rosenbluth, one photon exchange approximation

Dramatic evidence of

inadequate interpretatio

n of

lepton scatterin

g experiments

Definitive test for many phenomenological models aiming to explain the GEp/GMp slopeInvestigate non-perturbative to perturbative QCD regionSet limit or observe pQCD asymptoticMost likely will investigate negative region

JLab12: measurements up to Q2 = 15 GeV2

18 Set 2008 JLab12.0

18 Set 2008 JLab12.0

18 Set 2008 JLab12.0

18 Set 2008 JLab12.0

18 Set 2008 JLab12.0

18 Set 2008 JLab12.0

Chamber Layout

2D xy strip Readout (COMPASS design)2 foils: 50x40 cm2 each400 m pitch4500 channels

Total Thickness: X0 < 0.7 %

3 GEM foils100x40 cm2-Single large foil not strictly required-Last foil segmented (to reduce hits ambiguity) ?

18 Set 2008 JLab12.0

GEM Principle

18 Set 2008 JLab12.0

SBS Primary Tracker