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Hall C Summer Workshop 2007

Hall C Summer Workshop 2007. Y. N. Strangeness Happens. P. Ed V. Hungerford University of Houston Hunger@uh.edu. What’s so NU about Hyper-NU-clear Physics ?. POGO – “Nuclear physics is not so new and not so clear either”

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Hall C Summer Workshop 2007

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  1. Hall C Summer Workshop2007 Y N Strangeness Happens P Ed V. Hungerford University of Houston Hunger@uh.edu Hall C Summer Workshop 2007

  2. What’s so NU aboutHyper-NU-clear Physics ? POGO – “Nuclear physics is not so new and not so clear either” All scientific development, at least at some level, is based on “Evolution” As an example, in 1959 Dalitz predicted the (1405) using a Dalitz plot. However, Strange Nuclear Physics offers new perspectives on the Hadronic Many-body Problem So What’s Nu about Strange Nuclear Physics ? Hall C Summer Workshop 2007

  3. kaonic atom kaonic nucleus K- K- Nuclear bound states K- nuclear states and K condensation is not new, but the prediction by Akaishi and Yamazaki, and subsequent claim of the experimental observation of tribaryons and anti-kaon bound states, has recently generated considerable theoretical and experimental interest. Strongly Attractive K- - N Interaction (optical potential) (1405) 27 MeV below the K- p threshold Strong K- - Nucleus interaction Strong shifts and widths in Kaonic Atoms- -The issue is the binding energy and widths of ħω levels- Re(VK-opt) ≈ 150-200 MeV Re(VK-opt) ≈ 50-60 MeV RMF phenomenology Chiral anti-K amplitude K- Atom data can be fit with either a shallow or a deep potential Hall C Summer Workshop 2007

  4. K- + pp K- + 3He MeV MeV K- + p MeV r fm r fm 1 2 3 1 2 3 0 0 r fm 1 2 3 0 -50 -50 L(1405) S+p S+p -50 S+p L+p L+p L+p -200 -200 -200 Shrinkage! -300 -300 -300 -400 -400 -400 -500 -500 -500 Y. Akaishi & T. Yamazaki, Phys. Rev. C 65 (2002) 044005 K- Nuclear bound states I = 0 K- pp A. Dote et al. r fm EK = -108 MeV Γ = 20 Mev ρ = ~10ρN Hall C Summer Workshop 2007

  5. (1115) X(K-pp)→p X’ K- Nuclear bound statesThe FINUDA Experiment at DAΦNE 6Li X(K-pp)→Λp -p K- pp 2370 Hall C Summer Workshop 2007

  6. K- Nuclear bound states(Weise -Theoretical Summary) p K p n Realistic anti-K-N Interaction Chiral SU(3) Dynamics + Coupled Channels Include S and P-wave Realistic N-N Interaction Short range repulsion is crucial Realistic anti-K-NN Absorption Imaginary component determines the width Variational and Faddeev calculations; Anti-K pp clusters may exist ; but B < 70 MeV, Γ ~100 ρ saturates < 2 ρ0 Narrow experimental structure, if it exists, is not understood Experimentally Structure is at least partially due to FSI However, Quasi-bound states in Heavier K- Nuclei are possible Hall C Summer Workshop 2007

  7. Nijmegen Potentials (Th. A. Rijken) Meson Exchange Potentials JPC = 0--+ ,η,η’,K JPC = 1-- ρ,ω,Φ,K* JPC = 0++ a0(962),f0(760),f0(993),κ1(900) JPC = 1++ a0(1270),f0(1285),f0(1460),K1(1430) Broken SUF(3) Gaussian Form Factors Soft two-pseudo-scalar meson exchange Fits to Experimental Data (NN Dominates) 20 free parameters (cutoff, coupling, F/(F+D), etc) Baryon-Baryon InteractionTheoretical Input Summary Quality fits and simultaneous description of NN, YN, and YY Realistic long range  included SUF(3) consistent 3S1(ΣN, I=3/2) repulsive; N p wave attractive B value consistent with hypernuclear data First movement toward rigorous QCD calculations of properties and intractions of nuclei (via EFT). Invaluable aid for Strangeness Nuclear Physics Hall C Summer Workshop 2007

  8. ab Initio Structure Calculations ofLight Hypernuclei In a systematic calculation of all S-shell single and double hypernuclei 4 H was bound but 3H was not bound S shell hypernuclei are sensitive to -Σ coupling and 3-body forces Hall C Summer Workshop 2007

  9. Vc ~ Sw+Ss~ -30 MeV Ss(L) = -gLss Sw(L) = gLww Vls ~ Sw-Ss ~ 0 MeV Hypernuclei provide; Baryon-meson octet coupling constants and vertices in a simple mean-field model; gσ, gω, fω Self-Energies ~ Schroedinger single particle potentials; mean-field  dynamical correlations; Systematics of Binding Energies Non-locality and density dependence of the interaction Hyperon-Nucleus Interactionin Bound Strange Nuclei fss2 I=1 total DWIA for (e;e’K + ) I=0 Hall C Summer Workshop 2007

  10. New Structure from Symmetry and Complementary Reactions The Strangeness degree of freedom allows the system symmetrize lowering the energy. α α ( K-,π- )  2- 1- 4+ 3- Super Symmetric 1- 2+ 9Be Analog (π+,K + ) 0+ SS 8Be Analog Hall C Summer Workshop 2007

  11. Quark Flow Diagrams Hall C Summer Workshop 2007

  12. Production Kinematics High Momentum Transfer Recoilless Production Hall C Summer Workshop 2007

  13. Effects of high momentum transfer Production of 56Fe Fe Target (K-,π-)in-flight Q F High Penetration Q F (π+,K+) (K-, π-)stop Q F Hall C Summer Workshop 2007

  14. V( r ) = V0 + VsSn* SY + VtS12 + Vls(L x S+) + Vals(L x S-) S12 is the usual spin-tensor operator S+- = ½(Sn +-SY) are the symmetric and anti-symmetric spin operators Hypernuclear γ’s(Tamura, Millener) Interesting to see that summation and cancellation between terms works to give a reasonable results. There are still Details to resolve , e.g. the 10B gs splitting, and a possible change in Δ for nuclei in the later p shell Hall C Summer Workshop 2007

  15. 12C p-shell states (Emulsion Data) K-stop + 12C → - + p + 11B 3 states 2+, 2+, 0+ with resolution ~160 keV p7p(P Shell) 6 hyperfine states 0+ p emission 11 MeV 2+ 2+ S Shell Core Excitations 12C Hall C Summer Workshop 2007

  16. Hypernuclear Structure FINUDA 12C(K-stop,π-)12C Targets 12C, 7Li, 51V Apply the inversion test Hall C Summer Workshop 2007

  17. Jlab Hall A Electromagnetic Production - Jlab 12 C(e,e’K+) 12 B Preliminary Jlab Hall C Binding and Separation Energies are important; consistent p-shell binding 16O binding Hall C Summer Workshop 2007

  18. Beam Energy Stability Value of absolute energy is not important ---------- 1. Must remain stable – Feedback lock 2. Absolute Value/angle – Must be Calibrated Locus Shifts as Energy and Angles vary Hall C Summer Workshop 2007

  19. 12B P Shell Structure Hall C Summer Workshop 2007

  20. Nuclear Matter S = 28 MeV Density Dependent NN and NL Dirac-Brueckner Vertices Hyperon-Nucleus InteractionTheoretical Input fss2 Density dependence is crucial Hall C Summer Workshop 2007

  21. Hypernuclear Level Decay Hall C Summer Workshop 2007

  22. Γπ_(L→ ｐ + π－) Γπ0(L → ｎ + π０ ) Mesonic q～100MeV/c Γm Weak DecayThe Baryon-Baryon Weak interaction 1/tHY =Γtot Γp(L +“ｐ”→ ｎ + ｐ) Γn(L +“ｎ”→ ｎ + ｎ) Γ2N (ΛNN →NNN) Non-Mesonic(NMWD) q～400MeV/c Γnm After much theoretical and experimental work Γn/Γp seems to be resolved Main problem was FSI but also heavy meson exchange is required, e.g. σ However the asymmetry is experimentally very small but theory predicts a reasonable negative value A consistent understanding is still lacking Hall C Summer Workshop 2007

  23. Single proton/neutron spectra from 5ΛHe and 12ΛC 10 Calculation by Garbarino et al. Theory: - 0.6～- 0.7 aNM=0.08±0.08+0.08 -0.00 W()p = 1 + Pαcos() Note that the mesonic decay seems understood. I thought I understood the difference as due to long range vs short behavior. If not why the ΔI = ½ rule? Are other processes important even for Γn/Γp? (example) Hall C Summer Workshop 2007

  24. N = n;p;d;t;3He;α = ; Ξ p YY YY N Spectroscopy of  and Ξ hypernuclei at J-PARC RG calculations of  and Ξ hypernuclei (e.g. 6Ξ He; 7ΞHe; 7ΞLi, 8ΞLi, 9ΞLi; 9ΞBe; 10ΞBe) Show interesting B ΞStructure due to spin, isospin potential Widths should be small ~6Mev α +x+N+ Ξ 28MeV α Threshold Ξ + p  28 MeV X Hall C Summer Workshop 2007

  25. Hybrid Emulsion Techniques E964 Layout Tagged (K-,K+) Production Emulsion Tracking for  Spectroscopy Similar Layout used for Charm studies at FNAL Consider A(D+,+)LcA ? Hall C Summer Workshop 2007

  26. Double Lambda Hypernuclei (Exp and Th B) BA B(A-1) B  B  M  Ref 4H 0.13 -0.12 -0.14 4107 <Exp>[1] 5H 2.04 3.26 -0.82 5038 Th[2] 5He 2.39 3.80 -0.98 5037 Th[3] 6He 3.12 7.25 1.0 5953 Exp[4] 6He 3.12 10.9 4.7 5953 Exp[5] 7He 4.18 9.36 <1.0> 6891 Exp[6] 10Be 9.71 17.7 -1.72 9665 Exp[7] 10Be or --- --- --- --- Exp[8] 13B] M(YYA) = M(A-2) + 2 M() - B; B = B  - 2 B(A-1) [1] PRL 87(01)132504 [4]PRL 87(01)212502 [7]PRL 11(63)29[2] PRL 89(02)172502 [5]PRL 17(66)782 [8]Pro.Th.Phy 85(91)87; PRC 44(91)1905[3]NP A754(05)91c [6]NP A754(05)103c NP A754(05)103c Hall C Summer Workshop 2007

  27. Re-analysis of the 4H Events K- + 9Be K+ + Y + X  + p + Y  + p + X’ Simulation of 7He Decay Hall C Summer Workshop 2007

  28. Strange Structures at High Densitymulti-hyperon states Neutron Stars Strange Quark Objects – Quark Hadronization 1. Coalescence in Heavy Ion Collisions 2. Strangelets Strange matter having approximately equal numbers of s,u,and d quarks interacting via QCD e.g. the H 3. Hadronic Matter Composite of hadrons interacting by QHD e.g. Neutron Stars 4. Quark matter High temperature and/or high density Hall C Summer Workshop 2007

  29. Systems With Multiple Strangeness can Be Stable Binding Energy for systems with at 208 Pb core with N I and II correspond to different parameter sets Stability against  = Ξ p Hall C Summer Workshop 2007

  30. Stability as a function of Density and Strangeness DDRH Hypermatter Equation of State (Binding Energy per Baryon) Minimum at 10% -content: B0=-18MeV at ρ0=0.21fm-3 fss2 I=1 total I=0 Hall C Summer Workshop 2007

  31. Inside a Supernova Extreme temp: photodissociates nuclei back to protons, neutrons and alphas. >8 M evolves ~107 yr 3000 km Core bounces 3x107 km Neutronisation: p+e-  n+ne Huge thermal emission of neutrinos ~5-10 seconds n n n n n n Dense core n* . . 10 km M M 100 km n n n n e++e- g+g ; g+g nx + nx(all flavours equally) r ~ few x rnuclear Hall C Summer Workshop 2007

  32. Stability at higher densities Σ- does not appear because Potential is repulsive Hall C Summer Workshop 2007

  33. Stability at higher densities Max. Neutron Star Mass as A Function of Radius Addition of Hyperons makes the EOS too Soft Hall C Summer Workshop 2007

  34. New Facilities Hall C Summer Workshop 2007

  35. MAMI C Plans PANDA New Facilities A1 Collaboration Gen, Gep, Gmp VCS 3He Structure and Correlation K Electroproduction& Hypernuclei A2 Collaboration Crystal Ball & TAPS Frozen Spin Target Recoil Polarization A4 Collaboration Parity violating ep scattering Production of Multi-strange systems p p Ξ- + Ξ+ p n Ξ- + Ξ0  Hypernuclei Ω Atoms γ Transitions 1.5 GeV KAOS Spectrometer Hall C Summer Workshop 2007

  36. New Facilities(Arends, Nakamura, Feliciello, Achenbach, Nagae) J-Lab Upgrade HES Improvement of rate and resolution Medium-A systems Other experiments are under discussion Hall C Summer Workshop 2007

  37. J-PARC New Facilities • J-PARC Construction: 2001 ~ • ~70% completed • Beam commissioning: LINAC( Dec., 06), RCS( Sep., 07), MR( May, 08) • Beam from MR: ~ end of 2008 • Day-1 Experiments in preparation • Ξ hypernuclei • Hypernuclear gamma-ray spectroscopy • Deeply-bound Kaonic nuclei, etc. Hall C Summer Workshop 2007

  38. Strangeness from Beginning to … end? Strange Nuclear Physics is more than nuclear physics revisited. It can illuminate features that are obscured in conventional nuclear systems. It offers a selective probe of the hadronic many-body problem. It is of little interest to reproduce nuclear physics with strange baryons. Experiments should illuminate a process where the addition of a hyperon adds a unique feature, e.g. three body forces, “polarization” of the medium, SU(3)f symmetry, multi-strangeness, etc, Hall C Summer Workshop 2007

  39. K- Atom Data from X-rays The Kaon is ~1000 x the mass of an electron So it orbits close to or within the nuclear radius Atomic states are modified by shifts and widths due to KN Interactions Sensitive to the tails of the Nuclear density Hall C Summer Workshop 2007

  40. 1000 Repulsive-type attractive KpX (KEK) M. Iwasaki et al, 1997 800 KpX 600 Izycki et al, 1980 DEAR widthG1s[eV] 400 200 Bird et al, 1983 Davies et al, 1979 -500 0 shifte1s[eV] Atomic States isospin dependent antikaon-nucleon scattering lengths aK-p = (a0 + a1)/2 aK-n = a1 Shift: 1s = - 193 ± 37 (stat.) ± 6 ev Width: 1s = 249 ± 111 (stat.) ±30ev However K- D data are inconsistent with DEAR results Hall C Summer Workshop 2007

  41. 12C S x 11C States Hall C Summer Workshop 2007

  42. Magnetic Moments 1 In RMF expect hypernuclear moments to be near the Schmidt limits 2 Σ mixing in JN = 0 core corrections small, but for JN = 1 moments can be suppressed by ~10-20% Hall C Summer Workshop 2007

  43. Stability at higher densities Rotating Neutron Star With Quark or mixed Phase Core Hall C Summer Workshop 2007

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