S.N.Nakamura Tohoku University Hall-A Meeting/JLab PAC40 14 June 2013

PR12-13-002A Study with High Precision on the Electro-production of the Lambda and Lambda Hypernucleiin the Full Mass Range S.N.Nakamura Tohoku University Hall-A Meeting/JLab PAC40 14 June 2013

QCD Lattice QCD Modarn baryon Interaction models Baryon Interaction S N Nakamura @ Tohoku Univ. Quark degree of freedom SUf(3) Symmetry Nuclear Force Hyperon Force Lots of NN scattering data Limited YN/YY scattering data Established Calculation Tech. Cluster Model Shell Model Mean Field Nuclear Structure Nuclear Structure Normal/Exotic nuclei Hypernuclei

S N Nakamura @ Tohoku Univ. 1 20 50 200 1057 A Objectives --- Hypernuclear Physics Elementary Process Neutron/Hyperonstar, Strangeness matter Strangeness electro-production Light Hypernuclei (s,p shell) Hyperonization Softening of EOS ? Extend Nuclear Force to Baryon Interaction CSB, LScoupling in large isospinhypernuclei Medium - Heavy hypernuclei Use L as a probe to see deep inside of nucleus Single-particle potential • U0(r), mL*(r), VLNN, ... • Collective motion of nucleons • Deformation of nuclei

HKS 1953 discovery of hypernucleus (emulsion with cosmic-ray, by Danysz and Pniewski) HES History of Hypernuclear Study 1970s CERN, BNL Counter experiments with Kaon beam 1980s BNL-AGS, KEK-PS Counter experiments with K/p beam 1998- g-spectroscopy with Hyperball 2000~ (e,e’K+) spectroscopy @ JLab E89-009 (2000),E97-104 (2004), E01-011 (2005), E05-115 (2009) Z(e-,e’K+)L(Z-1) reaction DAFNE (stop K) 2011~ Decay p Spectroscopy at MAMI-C

HKS HES History of Hypernuclear Study 2000~ (e,e’K+) spectroscopy @ JLab E89-009 (2000),E97-104 (2004), E01-011 (2005), E05-115 (2009) Z(e-,e’K+)L(Z-1) reaction 2011~ Pilot runs of decay p spectroscopy at MAMI-C

Characteristics of (e,e’K) HY study • Electromagnetic production • Convert Proton to Lambda : Mirror/iso-multiplet partners study well studied HY by (p,K), (K,p) Absolute energy calibration with L and S0 masses p(e,e’K+) L,S0 • High quality primary beam High energy resolution (< 1MeV) Thin enriched target

Challenge of (e,e’K) HY Study • Huge e’ Background due to Bremsstrahlung and Mfller scattering Signal/Noise, Detector • Less Hypernuclear Cross Section • Coincidence Measurement (e’, K+) Limited Statistics DC beam is necessary High Quality Electron Beam is Essential !

High Resolution, Large Solid Angle and Short Orbit Spectrometer (Hall-C) What we have developed at JLab RICH for good K ID (Hall-A) RICH HKS SC Septum SC Septum for charge separation (Hall-A) High Resolution Electron Spectrometer (Hall-C) HES

One of proposing program. JLab’s Hypernuclear Program To Date Phys. Rev. Lett. 90 (2003) 232502. Phys. Rev. C73 (2006) 044607. Phys. Rev. Lett99 (2007) 052501. Nucl. Phys. A835 (2010) 129. Phys. Rev. Lett. 103 (2009) 202501. Nucl. Phys. A835 (2010) 129. Analysis in progress. Preliminary result can be found in Nucl. Phys. A804 (2008) 125. Analysis in progress.

Hypernuclear Chart [LN] L 27 12 48 48 40 44 40 L L L L L L L B L K Tl K K K Sc Mg 4 H 208 L

Hall-A setup vs. Hall-C setup

Proposing Setup K(HKS) x HRS (e’) + K(HKS) x {ENGE (p) + HRS (p)}

Expected Yields >5 times more yield than E94-107 Much better S/N than E05-115

Expected Mass Resolution Calibration for independent K, e’ spectrometers. Established in E94-107. Absolute missing mass calibration with L,S0 masses Established in E05-115.

1. Elementary L, S0 Reliable data 1H(e,e’K+)L, S0 in low Q2 Proposing Programs 2. Few-body 2D(e,e’K+)[LN]Exotic bound state, LN int. 4He(e,e’K+)4LH LN CSB 3. Medium-heavy 40,44,48Ca(e,e’K+)40,44,48LK L’s S.E., iso-spin 27Al(e,e’K+)27LMg Tri-axial deformation 48Ti(e,e’K+)48LSc Level inv. due to L 4. Heavy 208Pb(e,e’K+)208LTl L in heaviest nucleus 5. Decay p Weak decay of light hyper-fragments

S.N.Nakamura Tohoku University Hall-A Meeting/JLab PAC40 14 June 2013