1. JLab Hypernuclear Workshop 27 th May 2014 Satoshi N Nakamura, Tohoku University HKS HES Results from Hall-C

2. Nuclear Force Lots of NN scattering data Nuclear Structure Normal/Exotic nuclei Established Calculation Tech. Cluster Model Shell Model Mean Field Hyperon Force Limited YN/YY scattering data Nuclear Structure Hypernuclei Baryon Interaction QCD Quark degree of freedom SU f (3) Symmetry Lattice QCD Modern baryon Interaction models

3. EM Interaction p to  primary e beam Characteristics of  hypernuclear study by (e,e’K) reaction Electron BG Small C.S. Coin. measure High Quality Beam Sophisticated Detectors

4. Three generation experiments at Hall-C  E89-009 (2000) : Existing spectrometers, SOS + Enge Proof of Principle  E01-011 (2005) : Construction of HKS, Tilt Method ,  0, 7  He, 12  B, 28  Al Light Hypernuclei  E05-115 (2009) : HES, new Beamline, Splitter ,  0, 7  He, 12  B, 52  V Light to medium-heavy Hypernuclei

5. Proof of Principle (E89-009, HNSS) Demonstrated that the (e,e’K) hypernuclear spectroscopy is possible! 12 C(e,e’K + ) 12  B PRL 90 (2003) 232502, PRC 73 (2006) 044607 Good energy resolution <900 keV (FWHM) ss pp

6. Improvement of the E89-009 experiment Resolution & acceptance are limited BG from Bremsstrahlung (200 MHz for e’ arm) Tilt Method N ew Spectrometer High resolution Kaon Spectrometer (HKS) The 2 nd Generation Experiment was approved by Jlab PAC19 E01-011 (Spokesmen: Hashimoto, Tang, Reinhold, Nakamura) Zero degree e’ measure

7. 2005 E01-011 (Hall C) First step to beyond p-shell hypernuclei ( 28  Al, 12  B, 7  He) Beam: 30 μA, 1.8GeV HKS: Δp/p=2 x 10 -4 [FWHM] Solid angle 16msr(w/ splitter) ENGE HKS Splitter Electron beam To beam dump Target Two Major Improvements New HKS Tilt Method

8.  n pp  n np   0.35 MeV 0.24 MeV Coulomb effect is small. Charge Symmetry Breaking Charge Symmetry Breaking Effect of  N interaction 4H4H 4  He cf) B( 3 H)-B( 3 He)-  B c = 764-693 = 71 keV

9. B  of light hypermultiplets Hiyama et al. PRC80.(2009) 054321 PTP 128 (2012) 105.  n np  p np  p n  7  Li*  p  7  Be p  n n  7  He 4H4H 4  He 10  B  n   10  Be  p   Experimental B   CSB NO reliable B  67 events 98 events 167 events 15 events 3 event 10 events Exp. Data : Emulsion

10. 7 Li(e,e’K + ) 7  He First reliable observation of 7  He w/ good statistics PRL 110 (2013) 012502. M.Juric et al. NP B52 (1973) 1 FWHM 0.63 MeV Last missing information of A=7 hypernuclear iso-triplet E01-011(HKS) 90 counts E05-115(HKS-HES) >500 counts

11. 2009 E05-115 Wide mass range hypernuclear spectroscopy ( 7  He~ 52  V ) HKS+ new HES spectrometers Tilt method suppress electron background by >10000 2.34 GeV e - γ e-e- 1.2 GeV /c K + 0.9 GeV e ’

12. 12 C(  +,K + ) 12  C @ BNL-AGS,KEK-PS 12 C(e,e’K + ) 12  B @ JLab Hall C Resolution ~ 2MeV Resolution ~ 1.6 MeV Resolution ~ 0.5MeV Absolute binding energy Excitation energy (gs energy from emulsion) JLab E05-115 12 C(e,e’K + ) 12  B Paper is going to submit soon.

13. 7  He spectrum of E05-115 T. Gogami, Doctor Thesis (Tohoku U.) 6 He : 2n halo E.Hiyama et al. PRC 80, 054321 (2009)

14. 7  He spectrum of E05-115 T. Gogami, Doctor Thesis (Tohoku U.) Assumed CSB potential may be too naïve Further study on A=4 hypernuclear systems

15. 10 B(e,e’K + ) 10 Λ Be + T. Gogami, Doctor Thesis (Tohoku U.)

16. Comparison of 10  Be and 10  B CSB off : +0.22 MeV CSB on : -0.02 MeV Experiments Theoretical calc.

17. Theory 52 Cr(e,e’K + ) 52 Λ V

18. 12  C : Ref. for all ( ,K) data Power of Absolute E Calib.

19. Measured hypernuclei & expected A dependence E05-115 Calculation from Y.Yamamoto ss pp dd ff gg

20. Present Status of  Hypernuclear Spectroscopy Updated from: O. Hashimoto and H. Tamura, Prog. Part. Nucl. Phys. 57 (2006) 564. 52  V

21. Summary  Three generations of experiment at JLab Hall-C two major magnetic spectrometers (HKS, HES) novel techniques in the last decade. E89-009 : Feasibility of (e,e’K) hypernuclear spectroscopy E01-011 : 7  He, CSB and first beyond p-shell 28  Al E05-115 : 7  He, 10  Be : CSB and detailed spectroscopy 12  B, best resolution & absolute B  calibration 52  V: First medium-heavy hypernucleus (e,e’K) HY spectroscopy is now established at JLab and JLab is unique. Next Step: Detailed structures for lighter targets Major shell structures for heavier targets