Post on 27-Mar-2015
E01-012 : Spin-DualityE01-012 : Spin-DualityAnalysis updateAnalysis update
Patricia Solvignon
Temple University, Philadelphia
Hall A Collaboration Meeting, June 23-24, 2005
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Hall C results
I. Niculescu et al., Phys. Rev. Lett. 85 (2000) 1182
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Understand transition between partons and hadrons
Study of higher twists
Spin and flavor dependence of quark-hadron duality
Access high xbj region if duality is demonstrated and well understood
X. Zheng et al., Phys. Rev. Lett. 92 (2004) 012004
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
E94-010 saw a hint of duality in g1(3He)
Figure from Seonho Choi
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Ran in January-February 2003
Inclusive experiment: 3He(e,e’)X
Measured polarized cross-sections differences and asymmetries
Form g1, g2, A1 and A2 for 3He
Spokepeople: N. Liyanage, J-P. Chen, Seonho ChoiGraduate Student: P. Solvignon
Test duality on the neutron SSF
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
(N+/ Q+ LT+)-(N-/ Q- LT-)A/ / ()
raw =
(N+/ Q+ LT+)+(N-/ Q- LT-)
Ncut Ntrial
oraw =
Ninc 3He det LT Nacc Ltarg p
Generate asymmetries and unpolarized cross sections
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
A/ / () exp
= A/ / () raw /(fN2
Ptarg Pbeam) oexp = o
raw - 2(N2
/ 3He)N
Apply correction for nitrogen dilution
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
A//()= //() / 2oborn
//() exp
= 2 A //()exp o
exp
//()= //() exp + R.C.
Form polarized cross section differences
Apply radiative corrections on //() and o
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Density evaluated for each run
EPR analysis almost done
NMR analysis completed (V. Sulkosky)
Target
Cross sections and asymmetries Detector efficiencies done
Nitrogen dilution done
1st pass radiative corrections
Preliminary results on 3He spin structure functions
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Pavg= 37%
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Running with Duke
Running with Exodus
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Agreement between left and right arms cross sections is at 2% level.
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
QFS model from J.W. Lightbody and J.S. O’Connell
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Elastic tail negligeable at all our kinematics
For 1st pass, used QFS as model for o
Used E94-010 spin structure functions as a model for the radiative corrections on //() for our lowest energy
Then used our own data
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
N2 dilution applied
1st pass radiativecorrections
and
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
raw with both arms combined
exp= raw - N
N corrected for density ratio
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Smoothed exp
After R.C., we obtain born
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
A// A
A1 = - D(1+ ) d(1+ )
(// + tan(/2) )
A// A
A2 = + D(1+ ) d(1+ )
MQ2 E 1g1 = 4e
2 E´ E +E´
MQ22 1g2 = 4e
2 2E´(E +E´)
(- // + E + E´ cos E´sin
)
(D and d depend of R)
Extract g1 and g2 directly from our data
Need external input of R to form A1 and A2
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
DIS fit : no Q2-evolution included here
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Large negative contribution of (1232)
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Still large negative contribution of (1232).But, at lower x, resonance data seem to oscillate around the DIS curve.
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
The (1232) disappears and the resonance data seems to approach the DIS behavior.
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
No resonance structure can be seen anymore.
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
DIS data on 3He
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
A1 is large and negative in the (1232) region.
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
A1 is still negative in the (1232) region.
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
The (1232) vanishes while the non-resonant background is rising. A1 becomes positive in the (1232) region.
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
The two highest Q2 data sets agree with each other and show the same trend as DIS data.
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
Finalize target analysis
2nd pass radiative corrections
Extract the neutron spin structure functions
Extract moments of structure functions (e.g. GDH sum rule, BC sum rule)
Final results expected by the end of 2005
Extra slidesExtra slides
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
June 23, 2005 P. Solvignon, Hall A Collab. Meeting
June 23, 2005 P. Solvignon, Hall A Collab. Meeting