# Presentation: 682963

## Hall C Summer Workshop2007

**Hall C Summer Workshop****2007**

**Ed V. Hungerford**
**University of Houston**
**Hunger@uh.edu**

**Strangeness Happens**

**Y**

**P**

**N**

## What’s so NU aboutHyper-NU-clear Physics ?

**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 ?**

## K- Nuclear bound states

**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. **

**   ****-The issue is the binding energy and widths of ħ****ω**** levels****-**

**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****   ****-**

**Re(V****K-****opt****) ≈ 150-200 MeV****	****Re(V****K-****opt****) ≈ 50-60 MeV**
**RMF phenomenology****	****	****Chiral anti-K amplitude**
**K****-**** Atom data can be fit with either **
**a shallow or a deep potential**

## K- Nuclear bound states

**E****K**** = -108 MeV**
**Γ**** = 20 Mev**

*r*  fm

**K****-**** Nuclear bound states**

**A. Dote et al.**

- I = 0
- K- pp

- ρ = ~10ρN

## K- Nuclear bound statesThe FINUDA Experiment at DAΦNE

**6****Li**

**X(K****-****pp)→****p X’**** **

**X(K****-****pp)→****Λ****p**
**                      ********-****p**** **

**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**
**Variational and Faddeev calculations;**
**	****Anti-K pp clusters may exist ;**
**               ****but B < 70 MeV, ****Γ**** ~100 **
**	****ρ**** saturates < 2 ****ρ****0**
**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**

## Baryon-Baryon InteractionTheoretical Input

**Nijmegen Potentials (Th. A. Rijken)**
**Meson Exchange Potentials**
**	****JPC = 0****--+****	****	********,****η****,****η****’,K**
**	****JPC = 1****--****	****	****ρ****,****ω****,****Φ****,K***
**	****JPC = 0****++****	****	****a****0****(962),f****0****(760),f****0****(993),****κ****1****(900)**
**	****JPC = 1****++****	****	****a****0****(1270),f****0****(1285),f****0****(1460),K****1****(1430)**
**Broken SU****F****(3)**
**Gaussian Form Factors**
**S****oft 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 ******** included **
**SU****F****(3) consistent**
**	****3****S****1****(****Σ****N, 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**

## ab Initio Structure Calculations ofLight 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**

## Hyperon-Nucleus Interactionin Bound Strange Nuclei

**Hyperon-Nucleus Interaction****in Bound Strange Nuclei**

**I=0**

**I=1**

**total**

**fss2**

**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**

**DWIA **
**for (e;e’K ****+**** )**

## α

**New Structure from Symmetry and**
**Complementary Reactions**

- (π+,K + )

- (  K-,π- )

- Super Symmetric

**9****Be Analog**

**SS**

**8****Be Analog**

**1-**

**2+**

**4+**

**3-**

**2-**

**0+**

**1-**

- 

**The Strangeness degree of freedom**
**allows the system symmetrize lowering **
**the energy. **

## Quark Flow Diagrams

**Quark Flow Diagrams**

## Production Kinematics

**Production Kinematics**

**Recoilless Production**

**High Momentum Transfer**

## Effects of high momentum transfer

**(K****-****,****π****-****)****in-flight**

**(K****-****, ****π****-****)****stop**

**(****π****+****,K****+****)**

**Effects of high momentum transfer**
**Production of ****56********Fe**

**Q F**

**Q F  **

**Q F**

**High Penetration**

**Fe Target**

## Hypernuclear γ’s(Tamura, Millener)

**V( r ) = V****0**** + V****s****S****n***** S****Y ****+ V****t****S****12**** + V****ls****(L x S****+****) + V****als****(L x S****-****)**
**S****12**** is the usual spin-tensor operator**
**S****+-**** = 1⁄2(S****n**** +-S****Y****) are the symmetric and anti-symmetric **
**           ****spin operators**

**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**

## 12C p-shell states

**12********C p-shell states**
**(Emulsion Data)**

**K****-****stop**** + ****12****C → ********-**** + p + ****11********B**
**3 states 2+, 2+, 0+ with resolution ~160 keV**

**S Shell**
**Core Excitations**

**p****7****p********(P Shell)**
**6 hyperfine states**

**11 MeV**

**2****+**

**2****+**

**0****+**

**p emission**

**12********C**

## Hypernuclear Structure

| # | -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 |

**Hypernuclear Structure**
**FINUDA**

**12****C(K****-****stop****,****π****-****)****12********C**

**Targets ****12****C, ****7****Li, ****51****V**

**Apply the inversion test**

## Electromagnetic Production - Jlab

**Electromagnetic Production - Jlab**

**12**** C****  ****(e,e’K****+****) ****12******** ****B**

**Jlab Hall A**

**Jlab Hall C**

**Preliminary**

**Binding and Separation**
**     ****Energies are important;****        **
**            ****consistent p-shell**
**             ****binding **
**        ****16****O binding**

## Beam Energy Stability

**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**

## 12B 

**P Shell Structure**

## Hyperon-Nucleus InteractionTheoretical Input

**fss2**

**Nuclear Matter        S******** = 28 MeV**

**Density Dependent NN and N******** Dirac-Brueckner Vertices**

**Density dependence is crucial**

## Hypernuclear Level Decay

**Hypernuclear Level Decay**

## Weak DecayThe Baryon-Baryon Weak interaction

**Weak Decay****The Baryon-Baryon Weak interaction**

**After much theoretical and experimental work ****Γ****n****/****Γ****p 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**

**Non-Mesonic(**_**NMWD**_**)**
**   ****q****~****400MeV/c****                 **

**Γ****π****_**** ****(********→ ****p ****+ π****-****)**
**Γ****π****0****  ****(******** → ****n ****+ π****0 ****)**

**Γ****p**** ****(******** +“****p”→ n ****+ ****p****)**
**Γ****n**** ****(******** +“****n”→ n ****+ ****n****)**
**Γ****2N**** (ΛNN →NNN)**

**Mesonic  **
**   ****q****~****100MeV/c**

**1/********HY ****=Γ****tot**

**Γ****m**

**Γ****nm**

## Single proton/neutron spectra from 5ΛHe and 12ΛC

**Single proton/neutron spectra from ****5****Λ****He and ****12****Λ****C**

**10**

**W(********)********p**** = 1 + ****P******** ****α**** ****cos(********)****       **

**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 ****Δ****I = 1⁄2 rule?**
**Are other processes important even for ****Γ****n/****Γ****p** **? (example)**

## α

**X**

- 28MeV

**α +x+N+ ****Ξ**

**Spectroscopy of ******** and Ξ hypernuclei at J-PARC**

**RG calculations of ******** and ****Ξ**** hypernuclei**
**(e.g. ****6**** ****Ξ**** He;**** 7****Ξ****He;**** 7****Ξ****Li, ****8****Ξ****Li, ****9****Ξ****Li; ****9****Ξ****Be; ****10****Ξ****Be)**
**Show interesting B ****Ξ**  **Structure**
**due to spin, isospin potential**
**Widths should be small ~6Mev**

- Threshold Ξ + p      
- 28 MeV

## Hybrid Emulsion Techniques

** ****E964 Layout**

** ****Similar Layout used for **
**Charm studies at FNAL**

** ****Consider A(D****+****,********+****)****L****c****A ?**

**Tagged (K****-****,K****+****) Production**
**Emulsion Tracking for ******
**Spectroscopy**

## Double Lambda Hypernuclei        (Exp and Th B )

**[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**

**M(****YY****A) = M(A-2) + 2 M(********) - B********;       ********B******** = B ******** -  2 B********(A-1)**

## Re-analysis of the 4H Events

**                                ******** ****+ p + ********Y**
**                                       ******** ****+ p + X’****                                              **

**Re-analysis of the ****4********H Events**

**Simulation of ****7********He Decay**

## Neutron Stars
 Strange Quark Objects – Quark Hadronization

**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**

**Strange Structures at High  Density****multi-hyperon states **

**Neutron Stars**
** ****Strange Quark Objects – Quark Hadronization**

## 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  **

## Stability as a function of 

**I=1**

**total**

**fss2**

**Minimum at 10% ********-content:  B****0****=-18MeV at ****ρ****0****=0.21fm****-3**

**DDRH Hypermatter Equation of State (Binding Energy per Baryon)**

**Stability as a function of **
**Density and Strangeness**

## Inside a Supernova

**Inside a Supernova**

- 

- 

- 

- 

- 

- Dense
- core

**100 km**

- M

- .

**3x10****7**** km**

**3000 km**

- 

- 

- 

- 

- 

- n*

**10 km**

- M

- .

- >8 M evolves ~107 yr

- Extreme temp: photodissociates nuclei back to protons, neutrons and alphas.

- Neutronisation:** p+e****-**** ******** n+********e**

**e****+****+e****-****  ********  ********+********  ; ********+********  ******** ********x**** + ********x****   ****(all flavours equally)**

****~ few x ****nuclear

- Huge thermal emission of neutrinos
- ~5-10 seconds

- Core bounces

## Stability at higher densities

**Stability at higher densities**

**Σ****-**** does not appear because**
**Potential is repulsive**

## Stability at higher densities

**Max. Neutron Star Mass as**
**A Function of Radius**

**Addition of Hyperons makes**
**the EOS too Soft**

## New Facilities

## New Facilities

**    **
**    ****p  p     ****Ξ**** ****-**** + ****Ξ**** ****+**
**    ****p n       ****Ξ**** ****-**** + ****Ξ****0**
**      ******** ****Hypernuclei**
**    ****Ω****  Atoms**
**     ****γ**** Transitions**

**New Facilities**

**MAMI C**
**Plans**

**A1 Collaboration**
**     ****Gen, Gep, Gmp**
**     ****VCS**
**     ****3****He Structure and Correlation**
**     ****K Electroproduction& Hypernuclei**
**A2 Collaboration**
**     ****Crystal Ball & TAPS**
**     ****Frozen Spin Target**
**     ****Recoil Polarization**
**A4 Collaboration**
**     ****Parity violating ep scattering**

**KAOS Spectrometer**

**1.5 GeV**

**PANDA**

## New Facilities(Arends, Nakamura, Feliciello, Achenbach, Nagae)

**New Facilities****(Arends, Nakamura, Feliciello, Achenbach, Nagae)**

**J-Lab**

**Upgrade HES**
**Improvement of rate**
**   ****and resolution**
**Medium-A systems**
**Other experiments are under **
**discussion**

## New Facilities

**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.

## Strangeness from Beginning 

**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,

## K- Atom Data

**from X-rays**

- Sensitive to the tails of
- the Nuclear density

- Atomic states are modified
- by shifts and widths
- due to KN Interactions

- The Kaon is ~1000 x
- the mass of an electron
- So it orbits close to or
- within the nuclear radius

## Atomic States

**However  K****- ****D data are inconsistent**
** ****with DEAR results**

**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**

## 12C

**S******** x ****11****C States**

## Magnetic Moments

**1 In RMF expect hypernuclear moments to **
**      ****be near the Schmidt limits**
**2 ********Σ**** mixing in J****N**** = 0 core corrections **
**      ****small, but for J****N**** = 1 moments can be suppressed by ~10-20%**

## Stability at higher densities

**Rotating Neutron Star**
**With Quark or mixed Phase**
**Core**