1.  4 He(e,e'p)X, April 13 and April 14, 2011, 16 hours Measured P miss at 0.153 to 1.0 GeV/c, x b = 1.24, Q 2 = 2 (GeV/c) 2 Extension of SRC 2 body data which measured P miss from 0.4 to 1 GeV/c Actual target thickness(20 cm), 20 K at 10 atm = 1x10 23 /cm 3 Target thickness from proposal(10cm) 6 K at 10 atm = 1.24x10 23 /cm 3 Students: S. Iqbal(CSULA), N. McMahon(CNU) Spokespersons: A. Saha, D. Higinbotham, F. Benmokhtar, S. Gilad, K. Aniol Hall A Collaboration Experiment 1

2. Motivation – Cross sections for 4 He(e,e'p) 3 H, x b =1.25 and Nucleon Correlations 4 He is fundamental for nuclear microscopic theory. Theory must include many body forces for the 4 body system. First measurement of 4 He(e,e'p)X at this value of x b >1. Theory should be able to account for all the nucleon channels. X = 3 H, n+ 2 H, n+n+p Compare to theoretical cross sections ( 4 He(e,e'p) 3 H, x b =1.25) Compare to F. Benmokhtar results at 3 He(e,e'p)X (x b =1) for 2 body absorption peak in continuum. 2

3. 755 MeV/c 625 MeV/c 500 MeV/c 380 MeV/c 150 MeV/c 800 MeV/c Under analysis 0.153 GeV/c 0.353 GeV/c 0.500 GeV/c 0.625 GeV/c 0.755 GeV/c 0.800 GeV/c 4 He(e,e'p)X Missing Energy For central kinematics triton 2 body absorption

4. Steps in the Analysis for 4 He(e,e'p) 3 H We have overlapping missing momentum bins for 0.153 and 0.353 GeV/c kinematic settings Divide missing momentum into 50 MeV/c bins in data Divide missing momentum into 50 MeV/c bins in simulation Compare data from two kinematic settings using simulation Efficiencies TBD e.g. dead time, acceptances, target density and beam heating effects, match (w,q) cuts 4

5. Preliminary triton yields/electron - Simulation assumes uniform illumination of spectrometer apertures. Have received theory RDWA from Madrid Next step to include theory in simulation. 5

6. E miss (MeV) F. Benmokhtar, et al. E89044 Phys.Rev.Lett.94:082305,2005 3 He(e,e'p)X, Q 2 =1.55 GeV 2, x b = 1 Similar 2 body absorption seen in 3 He – needs 3bbu to fit cross section

7. Next Steps Get experimental cross sections Get more theory calculations for 2 body. We have Madrid’s calculations now Need theory for 3 body. We have promises. Extract the Effective Density and compare to 3 He. See if there is scaling! 4 He(e,e'p)X x b = 1.25, Q 2 = 2 (GeV/c) 2 0.755 GeV/c 0.625 GeV/c 0.500 GeV/c 0.353 GeV/c 0.153 GeV/c L E miss

8. Extra Slides for backup

9. Semi-Inclusive A(e,e’p)X probes a p-n pair? PmPm -P m p = q-P m q,  PmPm e e’ 3 He(e,e'p)X, Q 2 =1.55 GeV 2, x b = 1 Jlab-E89044 Hall A experiment. Example: 9 Missing Energy

10. Effective Density Distribution 3 He(e,e'p)X, Q 2 =1.55 GeV 2, x b = 1 -J. M. Laget Calculations (Fadeev WF and Paris Potential ( diagramatic approach) -Also available are calculations from C. degli-Atti et al., using realistic wave function with generalized Eikonal approximation for FSI. -Conclusions: Both Correlations in initial state and Final State Interactions play a role in this strength.