Formation of kaon bound statesby kaon beam

J. Yamagata (Nara Women’s Univ.)
H. Nagahiro (RCNP, Osaka Univ.)
S. Hirenzaki (Nara Women’s Univ.)

J. Yamagata, H. Nagahiro, Y. Okumura and S. Hirenzaki,
Prog. Theor. Phys. 114, 301 (2005)
J. Yamagata, H. Nagahiro and S. Hirenzaki,

Phys. Rev. C 74, 014604 (2006)

Introduction

R. Seki, C. E. Wiegand Ann. Rev. Nucl. Part. Sci. 25(75)241.
C. J. Batty, E. Friedman and A. Gal, Phys. Rep. 287(97)385.
S. Hirenzaki et al., Phys. Rev. C61(00)055205.
many others…….

 Study of Kaonic Atoms … for long time

To know the kaon properties at finite density, K-Ainteraction
 X-ray spectroscopyDeeply bound state were not observed

Deeply bound pionic atoms observed with (d,3He) reactions
New facility J-PARC … coming soon!!

We can expect kaonic bound states formationby using the (K-,p) reactions
 Theoretical (K-,p) spectra
Important!! Before experiment.
Introduction
 Our Studies
Kishimoto Group, Iwasaki, Suzuki Group, FINUDA GroupAkaishi, Yamazaki, DoteOset, Toki --- Recent activities on kaonic nuclei studies.

Theoretical Comprehensive Spectra
We can also check the contributions
from Kaonic Nuclear states in the calculated spectra

Kaonic Atoms and Kaonic Nuclei
 Structure of Kaon-Nucleus bound systems (Atom + Nucleus)
Energy-Dependent optical potentials
Chiral Unitary Model, Phenomenological Model Theoretical formation spectra in (In-Flight K-,p) reaction（RESONANCE DIP was reported in PRC 74(06)014604
by J. Yamagata, H. Nagahiro, S. Hirenzaki)Introduction
 Kaonic Atoms --Target -- 12C,
Final
State16O,-- 11B-K-In-flight(K-,p) reaction
40Ca,120Sn,208Pb

119In-K- Spectrum
 Kaon-Nucleus optical potential“Shallow”?
“Deep”?
 Contributions of Kaonic Nuclear state(Smooth background for atomic states)

Formulation -- Structure
 Klein-Gordon equation

Chiral Unitary Model[A. Ramos, E. Oset, NPA671(00)481][Hirenzaki, Okumura, Toki, Oset, Ramos, PRC61(00)055205]

AtomAtomPhenomenological Model[Batty, Friedman, Gal, Phys. Rep. 287(97)385]

AtomEnergy Level– Kaonic Atom –Observed

Not Observed!!
5g5g

Formulation -- Reaction
Green Function Method

In-Flight(K-,p)J. Yamagata et al., Phys. Rev. C 74 (06) 014604

O. Morimatsu,Morimatsu, K. Yazaki NPA435(85)727, NPA483(88)493: Elementary cross section (Exp. data): Green function for K interacting with the nucleus



Excited states of daughter nuclei( deep proton hole states)

γ decay width(Not negligible!)

We only consider ground state of nuclei in final states.

Energy Spectrum
Chiral Unitary Model
Atomic State

Atomic StateEnergy Spectrum

12C(K-,p) T =600 MeVK

 Proton hole state – 1p3/2Chiral Unitary

Phenomenology

Energy Spectrum

12C(K-,p) T =600 MeV
K

 Proton hole state – 1p3/2
Chiral Unitary
1s

Phenomenology
1s2p

2s2p

Dip !!

Dip !!

These are very interesting structures !!

2sEnergy Spectrum

12C(K-,p) T =600 MeV
K

 Proton hole state – 1p3/2
Chiral Unitary

These are very interesting structures !!

Phenomenology

Energy Spectrum

12C(K-,p) T =600 MeV
K

 Proton hole state – 1p3/2

Chiral Unitary
Phenomenology

These are very interesting structures !!
We need high energy resolution in this case.

Energy Spectrum

120Sn(K-,p) T =600 MeV
K

 Proton hole state – 1g9/2
Chiral Unitary

Phenomenology

Energy Spectrum

120Sn(K-,p) T =600 MeV
K

 Proton hole state – 1g9/2
Chiral Unitary
1s 2p

3d 2s

4f

Phenomenology
1s 2p

3p

These spectra are also interesting.

3d 2s4f

3p

Energy Spectrum

120Sn(K-,p) T =600 MeV
K

 Proton hole state – 1g9/2
Chiral Unitary

Phenomenology• Robust prediction
while• Insensitive to potentials

These spectra are also interesting
interesting.and resemble each other.

Summary Study of Kaonic Atoms

To know the kaon properties at finite density.
 Deeply bound atomic states have not been
observed yet.
 Our studyStructure New deeply bound atomic states are expected.

Reaction
 Not simple peak structure. But dips,etc.

shapes Peaks are expected!! (12C, 120Sn, other nuclei) ‘Robust prediction!’ while ‘Insensitive?’

Further investigations.

Future Work
 Kaonic atom



In-Flight(K-,n) reaction
Systematically

Stopped(K-,N) reaction(kinematically different cases) Experimental feasibilitiesJ-PARC DAΦNE

etc.