LEDAF. Garibaldi - Riunione CIII-Trieste 18/09/06

- LEDA (resp. E. Cisbani, F. Garibaldi)

Fisica Adronica e Nucleare a Jefferson Lab- Elettroproduzione di stranezza su nucleoni e nuclei- Struttura degli adroni (transizione N-> Delta)- Struttura di Spin del nucleone (neutrone)- Violazione della parita’ nello scattering elastico di elettroni su nucleoni e nuclei

- Sezioni di Bari e Roma1/Sanita

- Ricercatori coinvolti:11 (4.6 FTE)

- Tecnici: 7

- Spokespersonship in 7 esperimenti ad alto rating

- (3 esperimenti approvati a Gennaio 2006 (rating A))

- (2 in run nel 2007)

- “oggetti” costruiti: Target ad acqua (O-16, H), Gas Cherekov, Aerogel Cherenkov, Setti magnetici a superconduttore, RICH

- Stato di “salute” molto buono, anche in prospettiva Stato di “salute” molto buono, anche in prospettiva (fisica di (fisica di

prima qualita’ ben inserita nel quadro della road map. Impatto su altre prima qualita’ ben inserita nel quadro della road map. Impatto su altre

aree (astrofisica etc)aree (astrofisica etc)

•35 Experiments completed, 81 days scheduled for the next 12 months

•Backlog ~4.7 years (annual average for Hall A is ~75 days at full funding)

Number Approved

Days Approved

Polarized beam

A status

Number Completed

Days run

Number Jeopardized

Days to be run

Nucleon and Meson Form Factors/Sum Rules

12 212 10 8 10 212 2 0

Few Body Nuclear Properties

18 281 9 4 11 165 6 116

Properties of Nuclei 10 180 1 2 5 76 6 104

N* and Meson Properties 8 157 7 3 5 98 2 59

Strange Quarks and Parity Violation

8 196 5 7 4 123 1 73

Total 56 1026 32 24 35 674 17 352

Conditionally Approved

0

0

0

0

0

Hall A Approved Proposals PAC 4-29

• B. Anderson et al., Extraction of the Neutron Magnetic Form Factor from Quasi-Elastic 3He(e,e’) at Q2 = 0.1 - 0.6 GeV2, PRC, nucl-ex/0605006.

• B. Hu et al., Polarization Transfer in the d(e,e’p)n Reaction up to Q2 = 1.61 (GeV/c)2, PRL, nucl-ex/0601025.• J. Kelly et al., Recoil Polarization Measurement for Neutral Pion Electroproduction at Q2 = 1 (GeV/c)2 near the

Delta Resonance, PRC, nucl-ex/0509004.• Geraud Laveissiere, et al., Photon Electroproduction from Hydrogen at Backward Angles and Momentum

Transfer Squared of Q2 = 1.0 GeV2, PRL; hep-ex/0406062.

• K.A. Aniol et al., Constraints on the nucleon strange form factors at Q2 ~ 0.1 GeV2, PLB 635, 275 (2006).• K.A. Aniol et al., Parity-violating electron scattering from 4He and the strange electric form factor of the

nucleon, PRL 96, 022003 (2005).• S. Escoffier et al., Accurate measurement of the electron beam polarization in Jlab Hall A using Compton

polarimetry, NIM A551, 563 (2005).• K. Kramer et al., The Q2-dependence of the neutron spin structure function gn

2 at low Q2, PRL 95, 142002 (2005).

• J.J. Kelly et al., Recoil polarization for delta excitation in pion electroproduction, PRL 95, 102001 (2005).• V. Punjabi et al., Proton Elastic Form Factor Ratios for Q2 = 3.5 GeV2 by polarization transfer, PRC 71, 055202

(2005).• L.Y. Zhu et al., Cross Section Measurements of Charged Pion Photoproduction in Hydrogen and Deuterium

from 1.1 to 5.5 GeV, PRC 71, 044603 (2005).• Zein-Eddine Meziani et al., Higher Twists and Color Polarizabilities in the Neutron, PLB 613, 148 (2005)• D.J. Hamilton et al., Polarization transfer in proton Compton scattering at high momentum transfer, PRL 94,

242001 (2005).• Marat Rvachev et al., The Quasielastic 3He(e,e'p)d Reaction at Q2 = 1.5 GeV2 for Recoil Momenta up to 1

GeV/c, PRL94 192302 (2005).• Issam Qattan et al., Precision Rosenbluth measurement of the proton elastic form factors, PRL 94, 142301

(2005).• Fatiha Benmokhtar et al., Measurement of the 3He(e,e'p)pn reaction at high missing energies and momenta,

PRL94, 082305 (2005).

• Total number of Hall A publications: PRL+PLB 26+2, PRC 13+2, NIM 12.

• Average time from completion of experiment to submission 20 months with 75% within 3 years.

• At present 5 experiments that have not submitted a manuscript more than 3 years after completion

Publications (incl. submissions) in 2005/6

• Hypernuclear Spectroscopy: 12C (final) and 16O,9Be (preliminary) high quality data available. First publication soon (draft ready). Extension to heavier hypernuclei (52Cr, 208Pb) (+7Li?) under evaluation

• Recently good results on Parity (Happex) and Spin structure of neutron

• 3 experiments approved in January (high rate, A!high rate, A!)

– PREX: measurement of neutron skin in Lead (running in 2008-2009)

– Transversity: 2 experiments approved on nucleon spin structure (runnning in 2007)

– Correlation and relativistic effects (208Pb(e,e’p)207Tl) in the nuclear medium (running in 2007)

World of matter made of u, d, s quarks

ordinary nuclei

, hypernuclei

, hypernuclei

Neutron-rich nuclei

Proton-rich nuclei

higher density

Nu ~ Nd ~ Ns

Strangeness in neutron stars ( > 3 - 4 0 )

Strange hadronic matter (A → ∞)

3-dimensional nuclear chart

interaction

HYPERNUCLEI and

ASTROPHYSICS Strange baryons may appear in neutral b-stable matter through process like:

€

n + e− → Σ− + ν e

The presence of strange baryons

in neutron stars strongly affect their properties. Example: mass-central density relation for a non-rotating (left) and a rotating (right) star

The effect strongly depends upon

the poorly known interactions of strange baryons

More data needed to constrain theoretical models.

Hall A

charge symmetry breaking?

Monte Carlo simulation of 12B excitation-energy levels produced on 12C target

12C(e,e’K)12B

a cb d

( )( )

)())((3

(Tensor) )(

orbitspin )(

orbitspin )(

spin)(spin )(

(central)V )(

12

12

0N

ΛΛ

Λ

ΛΛΛ

Λσ

Λ

σ⋅σ−⋅σ⋅σ=

+

−σ⋅+

−σ⋅+

−Δσ⋅σ+

=

NN

T

NNNSO

NSO

N

rrS

TSrV

SrV

SrV

rV

rVV

rr

l

l

Absolute and relative positions of “resolved” levels a,b,c,d, may provide information on parameters of -N interaction potential and its terms (spin-spin, spin-orbit, tensor,..)

States of p-shell hypernuclei: there are just five independent pNs two-body matrix elements that can be put into one-to-one correspondence with single radial integrals of the average central, central spin-spin, spin-orbit, nucleon spin-orbit, and tensor interactions (V, , S, SN,T)

1/2

1-

3/2

2-

(3+,2+)

2+

Admixture ???

The energies of the 1/2- and 3/2-

levels of the core araised

primarily by the SN term because

the interaction lN. SN changes the

spacing of the core levels (the

magnitude can be changed by

changing SN or changing the p-

shell w.f. of the core)

The overall excitation energy of these states depends on energy separation of the p and s single particle states.

Essentially degenerate 2 and 3 dominate in the main p-shell peak (~ 11 MeV). The 1.9 MeV higher peak is 1/2-p3/->2

The good resolution of the (e,e’K) reaction may enable a limit to be put on the spacing of 2 and 3

The “sixth” peak“sixth” peak should be due, in the simplest model, to states based on core states with positive-parity and the lambda in an s state that mix with negative-parity core states coupled to p.

€

1+€

1+

€

1+

€

2+

s states

p states

€

1+g.s. CrossSection =

4.63.00 nb/(GeV sr2 )

Stat = 4.3 %Syst = 20 %

Theory =4.26 nb/(GeV sr2 ) !!!

K-N and K- x-section,forward photo production poorly known: surprisingly good agreement

---------- Forwarded message ----------Date: Mon, 10 Apr 2006 16:41:58 -0400From: Jay Benesch <benesch@jlab.org>To: Guido Maria Urciuoli <Guido.Maria.Urciuoli@roma1.infn.it>Subject: Re: about last friday's phone meeting: the "NOT" plot (fwd)

Please forgive my delay in responding to your emails of April 2 and April 10. I skimmed today's and haven't opened any of the ps files from the second. I have been immersed in trying to reduce the halo seen bythe G0 experiment, in part because I was "awarded" authorship on resulted papers in response to past and expected effort.

Skimming today's message, exactly zero reading on the 1C12.XPOS value suggests a problem rather than a real value, as you surmise. Since we lock the horizontal beam position at that location, it's possible to have only a few microns, but exactly zero is suspect. 15 microns is not an unreasonable cutoff.

More when I get out from under G0, which likely won't be until the end of the month. I'm on shift in the counting house Tuesday-Thursday thisweek and next.

Jay

trying to improve (Guido's analysis)

FWHM~ 600 KeV

Energy resolution issue

H. Hotchi et al., Phys. Rev. C 64 (2001) 044302 H. Hotchi et al., Phys. Rev. C 64 (2001) 044302

E94-107 Hall A Experiment Vs. KEK-E36912C(e,e’K)12B

12C(e,e’K)12B

12C(,K+)12C12C(,K+)12C

€

7

calculations by M. Sotona and J. Millener

E94-107 Hall A Experiment Vs. FINUDA (at Dane)

12C(e,e’K)12B12C(e,e’K)12B

E94-107 Hall A Experiment Vs. HallC E89-009

12C(e,e’K)12B12C(e,e’K)12B 12C(e,e’K)12B

12C(e,e’K)12B

Miyoshi et al., PRL 90 (2003) 232502.

New analysis

- energy resolution ~ 750 KeV, the best achieved in hypernuclear production experiments

- work is in progress to further improve the resolution (~500 KeV) (optical data base not fully optimized yet)

- first clear evidence of excited core states at ~ 2.5 and 6.5 MeV with high statistical significance

- the width of the strong ppeak and the distribution of strength within several MeV on either side of this peak can put constraints on the hypernuclear structure calculations

-suggestion for a peak at 9.6 MeV excitation energy (admixture ??)

Hall A - Two High Resolution SpectrometersHall A - Two High Resolution SpectrometersQDQ - Momentum Range: 0.3 –4 GeV/c p/p : 1 x 10-4 – p = =-5% - –mr

1 (+1) Cherenkov threshold aerogels

+ RICH in the hadron

spectrometer + septum magnet

Chϑ

Pion rejection factor ~ 1000

Superconducting Septum magnets

RICH detector unambiguous K identification

LEDA contribution for experiments in Hall A (performed and planned)

12.5° 6 ° (>Mott cross section)

Aerogel Kaon selection

RICH Kaon selection

12C(e,e’K)12B12C(e,e’K)12B

€

Signal

Bckgnd= 2.5

€

Signal

Bckgnd> 7

Spectroscopy analysis of 12B : Aerogel vs. RICH K-selection

Dilepton pair

Beam Pipe

HBD Gas Volume: Filled with CF4 Radiator (nCF4=1.000620, LRAD=50 cm)

Cherenkov light forms “blobs” on an image plane(rBLOB~3.36cm)

Triple GEM detectors(12 panels per side) Space allocated

for services

Windowless Cherenkov DetectorRadiator gas = Avalanche Gas

Electrons radiate, but hadrons with P < 4 GeV/c do not

Pcb pad readout (~ 2x2 cm2)

5 cm

55 cme-

e+

Pair Opening

Angle

(Phenix) The HBD Detector

CsI photocathode covering GEMs

The Evaporator

Evaporation Chamber Quantum Efficiency Station

Magnetically coupled driver for moving the GEMs inside the vacuum.

on loan from INFN Roma

Entrance Foyer

Level of Clean Roomevaporator

glove box

GEMstorage vessel

laminar flow hood

x-coordinate across GEM

Rel

ativ

e Q

E

(%)

40

0

9Be(e,e’K)9Li

a c db

( )( )

)())((3

(Tensor))(

orbitspin)(

orbitspin)(

spin)(spin)(

(central)V)(

12

12

0N

ΛΛ

Λ

ΛΛΛ

Λσ

Λ

σ⋅σ−⋅σ⋅σ=

+

−σ⋅+

−σ⋅+

−Δσ⋅σ+

=

NN

T

NNNSO

NSO

N

rrS

TSrV

SlrV

SlrV

rV

rVV

rr

Monte Carlo simulation of 9Liexcitation-energy levels

Produced on 9Be target Excitation-energy levels of 9Lihypernucleus, especially from the first-doublet levels

a and b, would provide important information on S and T terms of the N interaction. Separation of c and d doublets may provide information on the spin-orbit term SN

Missing energy (MeV)

Cou

nts

/ 2

00 k

eV

Red line: Benhold-Mart (K MAID)

Blue line: Saghai Saclay-Lyon (SLA)

Curves are normalized to the g.s. peak.

Red line: Benhold-Mart (K MAID)

Blue line: Saghai Saclay-Lyon (SLA)

Curves are normalized to the g.s. peak.

E-94107: Very Preliminary Results on 9Be target

0

1.6

0 2 4 6 8 10 12

Millener w.f.'s

Theoretical model for 16N excitation-energy on 16O target

The structure of underlying nucleus 15N is dominated by:

(i) J=1/2-proton-hole state in 0p1/2 shell - ground state

(ii) J=3/2- proton-hole state in 0p3/2 shell - Excited states at Ex = 6.32 MeV

Details of the hypernuclear spectrum at Ex ~ 17-20 MeV depend not only on -N residual interaction but also on the single particle spin-orbit splitting (difference in energy of 0p3/2 and 0p1/2 states)

Coupling of

p1/2 and p3/2

16O(e,e’K)16N

15N energy spectrum 16N energy spectrum

1H (e,e’K)1H (e,e’K)

16O(e,e’K)16N16O(e,e’K)16N

Low counting levels above Ethr.

16O(e,e’K)16N

16O(e,e’K)16N

16O(e,e’K)16N16O(e,e’K)16N

2005 E-94107:Preliminary spectra of missing energy

Analysis on 16N spectrum : FIT to the data

15N energy spectrum

16N energy spectrum

Analysis on 16N spectrum : COMPARISON with

models

High energy excited MULTIPLETS seems NOT WELL reproduced by the model.

-interaction here is in p-state, poorly known….

High energy excited MULTIPLETS seems NOT WELL reproduced by the model.

-interaction here is in p-state, poorly known….

Determining the magnitude of -N spin-orbit splitting is one of the key issues in hypernuclear spectroscopy. From the reaction 16O(e, e’K+)16N, information about an upper limit on doublet splitting of the first ex-cited J=1,2 doublet at excitation energies around 7 MeV can be obtained

Analysis on 16Nspectrum : COMPARISON with

models…SHIFTING “by hand” the positions of these MULTIPLETS in the model, while mantaining the predicted strength, a VERY GOOD agreement with the data can be reached.

…SHIFTING “by hand” the positions of these MULTIPLETS in the model, while mantaining the predicted strength, a VERY GOOD agreement with the data can be reached.

Work is in progress for a deeper physics interpretation.

Work is in progress for a deeper physics interpretation.

16O(e,e’K)16N16O(e,e’K)16N

E94-107 Hall A Experiment Vs. KEK-E336

16O(,K+)16O16O(,K+)16O

The energy spectra of the mirror hypernuclei 4H and 4He showed that the hyperon-nucleon interaction contains a non-negligible charge-symmetry-breaking part. Therefore it is extremely interesting to study other pairs of mirror hypernuclei, to compare their energy spectra and thus look for some additional evidence of these

effects comparing 16N with 16O known from hadron probe experiments.

16O(e,e’K)16N16O(e,e’K)16N

E94-107 Hall A Experiment Vs -ray spectroscopy at BNL

16O(K-, ) 16O16O(K-, ) 16O

Single Spin Asymmetry of 3He (e,e’h±)X on DIS

Physics Motivations:

• Nucleon Spin Structure: information on (poorly know) transverse quark

spin and (unknown) angular momentum contribution to the nucleon spin

• Non-perturbative QCD: non-singlet transverse quark distribution function

provides a clean Q2 evolution

Complementary to existing data (HERMES and COMPASS mainly) and unique for the coming years

First Time Measurement of neutron Transverse Target Single Spin Asymmetry:

Experimental Aspects

• CEBAF High Density Electron Beam

• High Density Transversely polarized 3He target almost pure polarized neutron

• RICH Detector for scattered hadron

(p/K) identification

. 26 International Institutions involved

• Approved experiment (Jlab) with highest

rating

• Expected to run 2nd semester of 2007

⎩⎨⎧=

Kh

πE. Cisbani, H. Gao, X Jiang,spokespersons

Single Spin Asymmetry of 3He (e,e’h±)X on DISE. Cisbani, H. Gao, X Jiang,spokespersons

Asymmetries consistent with zero

- strong flavor dipendence of the Collins and Sivers asymmetries

- Sivers K+ larger than +

- --> relevant contribution of sea quarks?

Compass Deuteron data (GPD 2006)

Hermes SSA p data (QCD-N06)

No direct data on neutron

Pk, max = 2.4 GeV/c

Identificazione dei K

Identifying correlations and relativistic effects in the nuclear medium

K. Aniol, A. Saha, J. M. Udias and G.M. Urciuoli Spokepersons

The experiment will use 208Pb, a doubly magic, complex nuclei, a textbook case for the shell model, measuring 208Pb(e,e’p)207Tl cross sections at true quasielastic kinematics and at both sides of q.

This has never been done before for A>16 nucleus

(1) First measurements in quasielastic kinematics on the paradigmatic shell model nucleus, 208Pb at high Q2. Accurate spectroscopic factors for separated shells will be obtained at several values of Q2.

(2) Strength for pmiss > 300 MeV/c will give insight into nuclear structure issues and will settle

the long standing question about the amount of long range correlations. They will be seen for the first time, if they are there.

(3) A new observable ATL for the five low lying states of 207Tl will be measured. ATL helps

distinguishing between relativistic and nonrelativistic structure of the wave functions.

Quasielastic kinematics:

xB = 1, q = 1 GeV/c , ω = 0.433 GeV/c

Determine momentum distributions:

0 < pmiss < 500 MeV/c

Determine Transverse-Longitudinal Asymmetry

ATL:

Impulse Approximation Limitation to 208Pb(e,e’p)207Tl reaction

( ) ( )( ) ( )φσφσ

φσφσ=+==−=

=0

0TLA

Nikhef data at xB ~ 0.18

PREX: Parity Violating Electron Scattering on Pb

Investigation of the nucleonic matter properties• Equation of state of neutron rich matter• Symmetry energy of dense matter• Strong connection with neutron star properties

Clean Measurement of neutron skin of leadby Left/Right Electroweak Cross Section Asymmetry:

( )( )⎥⎥⎦

⎤

⎢⎢⎣

⎡−−≈

+−

≡⇒2

22

PWIA

sin41QF

QFA

p

nW

LR

LRLR ϑ

σσ

σσ

As effective probe of neutron form factor Fn(Q2)

➥ Accurate neutron radius determination

Experimental Aspects

• CEBAF 80% Polarized Electron Beam

• Lead Foil Target

• Hall A Standard Spectrometers + Septum Magnets

z

R. Michaels and G.M. Urciuoli Spokepersons

⎥⎦

⎤⎢⎣

⎡−−=

⎟⎠

⎞⎜⎝

⎛

+⎟⎠

⎞⎜⎝

⎛

⎟⎠

⎞⎜⎝

⎛

−⎟⎠

⎞⎜⎝

⎛

=)(

sin4122 2

22

QF

QG

d

d

d

d

d

d

d

d

AP

WF

LR

LR θπασσ

σσ)( 2QF n

%1%3 =→=n

n

RdR

AdA

Lead ( Pb) Radius Experiment : PREX

Z of Weak Interaction :

Clean Probe Couples Mainly to Neutrons( T.W. Donnelly, J. Dubach, I Sick )

0

In PWIA (to illustrate) :

w/ Coulomb distortions (C. J. Horowitz) :

208

208Pb

E = 850 MeV, electrons on lead

06= Elastic Scattering Parity Violating Asymmetry

0≈

PREX & Neutron Stars

Crab Pulsar

( C.J. Horowitz, J. Piekarweicz )

R calibrates EOS of Neutron Rich Matter

Some Neutron Stars seem too Cold

N

Crust Thickness

Cooling by neutrino emission (URCA)

>− pn RR

Strange star ? Quark Star ?

Phase Transition to “Exotic” Core ?

0.2 fm URCA probable, else not

Combine PREX R with Obs. Neutron Star Radii

Explain Glitches in Pulsar Frequency ?

JLab Spin Structure Experiments

• Low-Intermediate Q2:– JLab Hall A: neutron/3He, longitudinal and transverse

Generalized GDH, E94-110, Q2 range 0.1 - 1 GeV2

Small Angle GDH, E97-110, Q2 range 0.02 – 0.3 GeV2

Spin Duality (E01-012): Q2 from 1-4 GeV2

E99-117: A1n at high x, E97-113: g2

n at Q2 of 0.5-1.5 GeV2, higher-twist– JLab Hall B : proton/deuteron, longitudinal EG1a/EG1b, Q2 range 0.05 - 4 GeV2

EG4: Q2 range 0.015 – 0.5 GeV2

– JLab Hall C: proton/deuteron, longitudinal and transverse RSS: <Q2> = 1.3 GeV2

• Semi-inclusive (approved): transversity, flavor decomposition.

JLab E94-010Neutron spin structure moments and sum rules at Low Q2

Spokespersons: G. Cates, J. P. Chen, Z.-E. Meziani

• Q2 evolution of spin structure moments and sum rules

• Results published in five PRL/PLB

• Review: Mod. Phys Lett. A 20, 2745 (2005)

• Preliminary results on 3He

GDH integral on 3He

Preliminary Q2

QuickTime™ e undecompressore

sono necessari per visualizzare quest'immagine.

JLab E97-110GDH Sum Rule and Spin Structure of 3He and Neutron with Nearly Real

Photons

Spokespersons: J. P. Chen, A. Deur, F. Garibaldi

• Measured generalized GDH at Q2 near zero for 3He and neutron

Slope at Q2 ~ 0 Benchmark test of

ChPT

• Data taken in 2003• Analysis underway• Prelimnary

asymmetries available now

QuickTime™ e undecompressore

sono necessari per visualizzare quest'immagine.

PREX: Parity Violating Electron Scattering on Pb

Investigation of the nucleonic matter properties• Equation of state of neutron rich matter• Symmetry energy of dense matter• Strong connection with neutron star properties

Clean Measurement of neutron skin of leadby Left/Right Electroweak Cross Section Asymmetry:

( )( )⎥⎥⎦

⎤

⎢⎢⎣

⎡−−≈

+−

≡⇒2

22

PWIA

sin41QF

QFA

p

nW

LR

LRLR ϑ

σσ

σσ

As effective probe of neutron form factor Fn(Q2)

➥ Accurate neutron radius determination

Experimental Aspects

• CEBAF 80% Polarized Electron Beam

• Lead Foil Target

• Hall A Standard Spectrometers + Septum Magnets

z

R. Michaels and G.M. Urciuoli Spokepersons

⎥⎦

⎤⎢⎣

⎡−−=

⎟⎠

⎞⎜⎝

⎛

+⎟⎠

⎞⎜⎝

⎛

⎟⎠

⎞⎜⎝

⎛

−⎟⎠

⎞⎜⎝

⎛

=)(

sin4122 2

22

QF

QG

d

d

d

d

d

d

d

d

AP

WF

LR

LR θπασσ

σσ)( 2QF n

%1%3 =→=n

n

RdR

AdA

Lead ( Pb) Radius Experiment : PREX

Z of Weak Interaction :

Clean Probe Couples Mainly to Neutrons( T.W. Donnelly, J. Dubach, I Sick )

0

In PWIA (to illustrate) :

w/ Coulomb distortions (C. J. Horowitz) :

208

208Pb

E = 850 MeV, electrons on lead

06= Elastic Scattering Parity Violating Asymmetry

0≈

PREX & Neutron Stars

Crab Pulsar

( C.J. Horowitz, J. Piekarweicz )

R calibrates EOS of Neutron Rich Matter

Some Neutron Stars seem too Cold

N

Crust Thickness

Cooling by neutrino emission (URCA)

>− pn RR

Strange star ? Quark Star ?

Phase Transition to “Exotic” Core ?

0.2 fm URCA probable, else not

Combine PREX R with Obs. Neutron Star Radii

Explain Glitches in Pulsar Frequency ?

Liquid/Solid Transition Density

Neutron EOS and Neutron Star Crust ( C.J. Horowitz, J. Piekarweicz )

FP

TM1Solid

Liquid

• Thicker neutron skin in Pb means energy rises rapidly with density Quickly favors uniform phase.

• Thick skin in Pb low transition density in star.

Fig. from J.M. Lattimer & M. Prakash, Science 304 (2004) 536.

Impact on Atomic Parity Violation• Low Q test of Standard Model

• Needs R to make further progress.

2

N

[ ] rdrZrNG

H eePWNF

PNC35/2 )()sin41()(

22ψγψρθρ∫ −+−≈

rr

0≈

APV

Isotope Chain Experiments e.g. Berkeley Yb

Conclusioni- Stato di “salute” molto buono - Stato di “salute” molto buono

- ipernuclei- ipernuclei

- struttura di spin del neutrone- struttura di spin del neutrone

- parita’- parita’

- 3 esperimenti ad alto rating approvati a gennaio - 3 esperimenti ad alto rating approvati a gennaio 20062006

- due in run nel 2007 (Transversity, Pb(e,e’p))- due in run nel 2007 (Transversity, Pb(e,e’p))

- uno 2008-2009 (PREX)- uno 2008-2009 (PREX)- collaborazione con il gruppo ipernuclei della sala C

- nuova proposta ipernuclei prossimo PAC ?

Hall A Schedule (Tentative!)

Long-Term Schedule

New Hall A 3He Results (preliminary)

QuickTime™ e undecompressore

sono necessari per visualizzare quest'immagine.

12

• Q2 evolution of moments of 3He spin structure functions

• B-C sum rule satisfied within uncertainties

Hall A E01-012 Preliminary Results: 1n and A1

3He

Spokesperson: N. Liyanage, J. P. Chen, S. Choi

g1/g2 and A1/A2 (3He/n) in resonance region, 1 < Q2 < 4 GeV2

• Study quark-hadron duality in spin structure

1n1

3He

x Q2

1n resonance comparison with pdfs

Color Polarizability: d2n (Hall A)

d2n with JLab 6 GeV and 12 GeV

(from B. Sawatzky)

• Projections with planned 6 GeV and 12 GeV experiments Improved Lattice Calculation (QCDSF, hep-lat/0506017)