Hall C Summer Workshop Y N P Ed V. Hungerford University of Houston [email protected] Aug 2007 Hall C Summer Workshop 2007 Σ Ξ.
Download ReportTranscript Hall C Summer Workshop Y N P Ed V. Hungerford University of Houston [email protected] Aug 2007 Hall C Summer Workshop 2007 Σ Ξ.
Hall C Summer Workshop 2007 Y N P Ed V. Hungerford University of Houston [email protected] Aug 2007 Hall C Summer Workshop 2007 Σ Ξ What’s so NU about Hyper-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 ? Aug 2007 Hall C Summer Workshop 2007 Σ Ξ K- Nuclear bound states Σ Ξ 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. kaonic atom K- kaonic nucleus 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 RMF phenomenology Re(VK-opt) ≈ 50-60 MeV Chiral anti-K amplitude K- Atom data can be fit with either a shallow or a deep potential Aug 2007 Hall C Summer Workshop 2007 K- Nuclear bound states Σ Ξ U Knucl MeV 0 -50 S+p K- + 1 2 U Knucl p MeV 3 r fm (1405) EK -27 MeV Γ 40 MeV 0 -50 S+p K- + 1 2 pp 3 r fm 2 KH EK -48 MeV UKnucl MeV 0 K- + 3He 1 2 -50 S+p Γ 61 MeV +p +p +p -200 -200 -200 -300 -300 -300 -400 -400 -400 -500 -500 -500 3 KH EK -108MeV Γ 20 MeV EK = -108 MeV Γ = 20 Mev Y. Akaishi & T. Yamazaki, Phys. Rev. C 65 (2002) 044005 Aug 2007 3 r fmr fm I=0 K- ppet al. A. Dote Hall C Summer Workshop 2007 Shrinkage! ρ = ~10ρN K- Nuclear bound states The FINUDA Experiment at DAΦNE Σ Ξ X(K-pp)→p X’ 6Li X(K-pp)→Λp p-p (1115) Aug 2007 Hall C Summer Workshop 2007 K- pp 2370 K- Nuclear bound states (Weise -Theoretical Summary) 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 Σ Ξ p K p n 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 Aug 2007 Hall C Summer Workshop 2007 Baryon-Baryon Interaction Theoretical Input Nijmegen Potentials (Th. A. Rijken) Meson Exchange Potentials JPC = 0--+ p,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) Summary Quality fits and simultaneous description of NN, YN, and YY Realistic long range pp included SUF(3) consistent 3S (ΣN, I=3/2) repulsive; N p wave attractive 1 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 Aug 2007 Hall C Summer Workshop 2007 Σ Ξ ab Initio Structure Calculations of Light Hypernuclei Σ Ξ In a systematic calculation of all S-shell single and double hypernuclei 4 H was bound but 3H was not bound S shell hypernuclei are sensitive to -Σ coupling and 3-body forces Aug 2007 Hall C Summer Workshop 2007 Hyperon-Nucleus Interaction in Bound Strange Nuclei Σ Ξ Hypernuclei provide; Baryon-meson octet coupling constants and vertices in a simple mean-field model; gσ, gω, fω Self-Energies ~ Schroedinger single particle potentials; mean-field dynamical correlations; Systematics of Binding Energies Non-locality and density dependence of the interaction Ss() = -gs s Vc ~ Sw+Ss~ -30 MeV Sw() = gw w Vls ~ Sw-Ss ~ 0 DWIA for (e;e’K + ) Aug 2007 Hall C Summer Workshop 2007 MeV New Structure from Symmetry and Complementary Reactions α α Σ Ξ The Strangeness degree of freedom allows the system symmetrize lowering the energy. ( K-,π- ) 21- 4+ 3- Super Symmetric 12+ 0+ 9Be Analog (π+,K + ) SS 8Be Analog Aug 2007 Hall C Summer Workshop 2007 Quark Flow Diagrams Aug 2007 Hall C Summer Workshop 2007 Σ Ξ Production Kinematics Σ Ξ High Momentum Transfer Recoilless Production Aug 2007 Hall C Summer Workshop 2007 Effects of high momentum transfer Production of 56Fe Fe Target Σ Ξ (K-,π-)in-flight QF High Penetration QF QF Aug 2007 Hall C Summer Workshop 2007 (π+,K+) (K-, π-)stop Hypernuclear γ’s (Tamura, Millener) Σ Ξ 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 Aug 2007 Interesting to see that summation and cancellation between terms works to give a reasonable results. There are still Details to resolve , e.g. the 10B gs splitting, and a possible change in Δ for nuclei in the later p shell Hall C Summer Workshop 2007 12 C p-shell states Σ Ξ (Emulsion Data) K-stop + 12C → p- + p + 11B 3 states 2+, 2+, 0+ with resolution ~160 keV p7p(P Shell) 6 hyperfine states 0+ p emission 2+ 2+ 11 MeV S Shell Core Excitations 12 Aug 2007 Hall C Summer Workshop 2007 C Hypernuclear Structure FINUDA 12C(K- - 12 stop,π ) C Targets 12C, 7Li, 51V Aug 2007 Hall C Summer Workshop 2007 Σ Ξ # -B (MeV) 1 -10.94±0.06 2 -8.4±0.2 3 -5.9±0.1 4 -3.8±0.1 5 -1.6±0.2 6 0.27±0.06 7 2.1±0.2 Electromagnetic Production - Jlab Σ Ξ Jlab Hall A Preliminary 12 C (e,e’K+) 12 B Jlab Hall C Binding and Separation Energies are important; consistent p-shell binding 16O Aug 2007 Hall C Summer Workshop 2007 binding Beam Energy Stability Σ Ξ 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 Aug 2007 Hall C Summer Workshop 2007 12 B P Shell Structure Aug 2007 Hall C Summer Workshop 2007 Σ Ξ Nuclear Matter S = 28 MeV Hyperon-Nucleus Interaction Theoretical Input Σ Ξ Density Dependent NN and N Dirac-Brueckner Vertices Density dependence is crucial Aug 2007 Hall C Summer Workshop 2007 Hypernuclear Level Decay Σ Ξ Aug 2007 Hall C Summer Workshop 2007 Weak Decay The Baryon-Baryon Weak interaction Σ Ξ Γm Γπ_ (→ ｐ + π－) Γπ0 ( → ｎ + π０ ) Mesonic q～100MeV/c Γnm Γp ( +“ｐ”→ ｎ + ｐ) Γn ( +“ｎ”→ ｎ + ｎ) Γ2N (ΛNN →NNN) Non-Mesonic(NMWD) 1/tHY =Γtot q～400MeV/c 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 Aug 2007 Hall C Summer Workshop 2007 Single proton/neutron spectra from 5 He and 12 C Λ Λ Calculation by Garbarino et al. aNM=0.08±0.08+0.08 -0.00 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 Σ Ξ W()pp = 1 + P α cos() Theory: - 0.6～- 0.7 Aug 2007 10 Spectroscopy of and Ξ hypernuclei at J-PARC RG calculations of and Ξ hypernuclei (e.g. 6 Ξ He; 7ΞHe; 7ΞLi, 8ΞLi, 9ΞLi; 9ΞBe; 10 N = n;p;d;t;3He;α 28MeV Show interesting B Ξ Structure due to spin, isospin potential Widths should be small ~6Mev YY = ; Ξ p α N X Aug 2007 Σ Ξ α +x+N+ Ξ ΞBe) YY Threshold Ξ + p 28 MeV Hall C Summer Workshop 2007 Hybrid Emulsion Techniques Σ Ξ E964 Layout Tagged (K-,K+) Production Emulsion Tracking for Spectroscopy Similar Layout used for Charm studies at FNAL Consider A(D+,p+)LcA ? Aug 2007 Hall C Summer Workshop 2007 Double Lambda Hypernuclei (Exp and Th B ) B A B(A-1) B B M Σ Ξ 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] -1.72 Exp[7] 10 Be 9.71 17.7 10 Be or --- --- 13 B --- Exp[8] ] M(YYA) = M(A-2) + 2 M() - B; [1] PRL 87(01)132504 [2] PRL 89(02)172502 [3]NP A754(05)91c Aug 2007 --- 9665 B = B - 2 B(A-1) [4]PRL 87(01)212502 [7]PRL 11(63)29 [5]PRL 17(66)782 [8]Pro.Th.Phy 85(91)87; PRC 44(91)1905 [6]NP A754(05)103c NP A754(05)103c Hall C Summer Workshop 2007 Re-analysis of the 4H Events Σ Ξ K- + 9Be K+ + Y + X p + p + Y p + p + X’ Simulation of 7 He Decay Aug 2007 Hall C Summer Workshop 2007 Strange Structures at High Density multi-hyperon states Σ Ξ 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 Aug 2007 Hall C Summer Workshop 2007 Systems With Multiple Strangeness can Be Stable Σ Ξ Binding Energy for systems with at 208 Pb core with N I and II correspond to different parameter sets Stability against = Ξ p Aug 2007 Hall C Summer Workshop 2007 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 Aug 2007 Hall C Summer Workshop 2007 Σ Ξ Inside a Supernova Σ Ξ Extreme temp: photodissociates nuclei back to protons, neutrons and alphas. >8 M evolves ~107 yr 3000 km Core bounces 3x107 km Huge thermal emission of neutrinos ~5-10 seconds Neutronisation: p+e- n+ne n n n 10 km n n* n n . M n 100 km Dense core n n . M n e++e- g+g ; g+g nx + nx (all flavours equally) r ~ few x r nuclear Aug 2007 Hall C Summer Workshop 2007 Stability at higher densities Σ Ξ Σ- does not appear because Potential is repulsive Aug 2007 Hall C Summer Workshop 2007 Stability at higher densities Σ Ξ Max. Neutron Star Mass as A Function of Radius Addition of Hyperons makes the EOS too Soft Aug 2007 Hall C Summer Workshop 2007 New Facilities Aug 2007 Hall C Summer Workshop 2007 Σ Ξ MAMI C Plans New Facilities Σ Ξ PANDA 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+ pn Ξ - + Ξ0 Hypernuclei Ω Atoms γ Transitions 1.5 GeV KAOS Spectrometer Aug 2007 Hall C Summer Workshop 2007 New Facilities (Arends, Nakamura, Feliciello, Achenbach, Nagae) Σ Ξ J-Lab Upgrade HES Improvement of rate and resolution Medium-A systems Other experiments are under discussion Aug 2007 Hall C Summer Workshop 2007 New Facilities Σ Ξ J-PARC 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. Aug 2007 Hall C Summer Workshop 2007 Strangeness from Beginning to … end? Σ Ξ 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 problem. It is of little interestmany-body 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, Aug 2007 Hall C Summer Workshop 2007 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 Aug 2007 Hall C Summer Workshop 2007 Σ Ξ Atomic States Repulsive-type KpX (KEK) M. Iwasaki et al, 1997 KpX 600 DEAR 200 -500 Aug 2007 Bird et al, 1983 400 Davies et al, 1979 width G1s [eV] 800 attractive isospin dependent antikaon-nucleon scattering lengths Izycki et al, 1980 1000 Σ Ξ aK-p = (a0 + a1)/2 aK-n = a1 Shift: e1s = - 193 ± 37 (stat.) ± 6 ev Width: G1s = 249 ± 111 (stat.) ±30ev However K- D data are inconsistent with DEAR results 0 shift e1s [eV] Hall C Summer Workshop 2007 12 C S x Aug 2007 11C States Hall C Summer Workshop 2007 Σ Ξ Magnetic Moments Σ Ξ 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% Aug 2007 Hall C Summer Workshop 2007 Stability at higher densities Rotating Neutron Star With Quark or mixed Phase Core Aug 2007 Hall C Summer Workshop 2007 Σ Ξ