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Prototype of kaonic nuclei “K - pp”. KEK Theory center J-PARC branch /IPNS Akinobu Doté. K - 中間子原子核、最近の状況. Y. Akaishi (Nihon/RIKEN), T. Yamazaki (RIKEN). Introduction Expanding the nuclear world Exotic properties of kaonic nuclei with - PowerPoint PPT Presentation
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K- 中間子原子核、最近の状況1. Introduction
• Expanding the nuclear world• Exotic properties of kaonic nuclei with a phenomenological KbarN potential
2. Variational calculation of K-pp with a chiral SU(3)-based KbarN potential
3. Current status of the K-pp study
4. Experiments related to Kbar nuclear physics
5. Summary and future plan
KEK Theory center J-PARC branch /IPNSAkinobu Doté
Y. Akaishi (Nihon/RIKEN), T. Yamazaki (RIKEN)
T. Hyodo (TITech), W. Weise (TU Munich)
東大駒場セミナー ’ 12.05.23 @ 東京大学駒場キャンパス
Prototype of kaonic nuclei “K-pp”
1. Introduction
Expanding the nuclear world原子核 = 陽子・中性子からなる有限量子多体系、 安定核 … 約300種
Large isospin 不安定核…約 3000 種、 RIBF @理研で展開
http://www.rarf.riken.go.jp/newcontents/contents/facility/RIBF.html
Expanding the nuclear world原子核 = 陽子・中性子からなる有限量子多体系、 安定核 … 約300種
Large isospin 不安定核…約 3000 種、 RIBF @理研で展開
Strangeness ハイパー核 … J-PARC (JAEA+KEK) で展開
Kaonic nuclei
Another form of nuclear system with strangeness
K-
Nucleus containing K- meson
What is Kaonic nucleus?
Nucleus
Hypernuclei…u
d sHyperon
baryon = qqq
Strangeness is introduced through baryons.
What is Kaonic nucleus?
Nucleus
Kaonic nuclei !
ubar
sK- meson
Strangeness is introduced through mesons …
meson = qqbar
quark (q) and anti-quark (qbar) pair
Leading actors
Key person
N
K
,0
,0
pn
938940
2 [ ]Mc MeV
1 1,2 2
J I
Baryon uududd
0K 498 10 ,
2J I Meson ds
K 494 us
14061 , 02
J I
Baryon uds
1116 Baryon
:1189, 0 :1193,:1197
:140, 0 :135
1 , 02
J I
1 , 12
J I
0 , 1J I
Baryon : , 0 : , :uu uds ds sd
Meson 1: , 0 : , :2
ud uu dd du
uds
Actors in Kbar nuclei
Supporting players
Excited state of Λ
940 p,n
1115 Λ
1190 Σ
p + K-1435Λ(1405)1405
1250 Λ + π
Σ + π1325E
nerg
y [M
eV]
940 p,n
1115 Λ
1190 Σ
p + K-1435Λ(1405)1405
1250 Λ + π
Σ + π1325E
nerg
y [M
eV]
Mysterious state; Λ(1405)Quark model prediction … calculated as 3-quark state
N. Isgar and G. Karl, Phys. Rev. D18, 4187 (1978)
qq q
Λ(1405) can’t be well reproduced as a 3-quark state!
observed Λ(1405)calculated Λ(1405)
Leading actors
Key person
N
K
,0
,0
pn
938940
2 [ ]Mc MeV
1 1,2 2
J I
Baryon uududd
0K 498 10 ,
2J I Meson ds
K 494 us
14061 , 02
J I
Baryon uds
1116 Baryon
:1189, 0 :1193,:1197
:140, 0 :135
1 , 02
J I
1 , 12
J I
0 , 1J I
Baryon : , 0 : , :uu uds ds sd
Meson 1: , 0 : , :2
ud uu dd du
uds
Actors in Kbar nuclei
Supporting players
Excited state of Λ
940 p,n
1115 Λ
1190 Σ
p + K-1435Λ(1405)1405
1250 Λ + π
Σ + π1325E
nerg
y [M
eV]
940 p,n
1115 Λ
1190 Σ
p + K-1435Λ(1405)1405
1250 Λ + π
Σ + π1325E
nerg
y [M
eV]
I=0 Proton-K- bound state with 30MeV binding energy? Not 3 quark state? ← can’t be explained with a simple quark model…
ubar
suu d
qq q
Leading actors
Key person
N
K
,0
,0
pn
938940
2 [ ]Mc MeV
1 1,2 2
J I
Baryon uududd
0K 498 10 ,
2J I Meson ds
K 494 us
14061 , 02
J I
Baryon uds
1116 Baryon
:1189, 0 :1193,:1197
:140, 0 :135
1 , 02
J I
1 , 12
J I
0 , 1J I
Baryon : , 0 : , :uu uds ds sd
Meson 1: , 0 : , :2
ud uu dd du
uds
Actors in Kbar nuclei
Supporting players
Excited state of Λ
940 p,n
1115 Λ
1190 Σ
p + K-1435Λ(1405)1405
1250 Λ + π
Σ + π1325E
nerg
y [M
eV]
Σπ channel is open at about 100 MeV below the Proton-K- threshold.
Interests of Kaonic nuclei
KNNN…
ΣπNN…
K nuclear state
Deeply bound below πΣ threshold (main decay channel)
Possible to exist as a quasi-bound state
with narrow width
• Nuclear structure change. Highly dense state. if the interaction is so attractive…
K-Proton
Λ(1405)
=
Kaonic nucleus
• Self-bound Kbar-nuclear systemK-
1. Free KbarN scattering data2. 1s level shift of kaonic hydrogen atom3. Binding energy and width of Λ(1405)
Phenomenological KbarN potential (AY KbarN potential)
Strongly attractive 0
KNIV
• Y. Akaishi and T. Yamazaki, PRC 52, 044005 (2002)
Λ(1405) = I=0 K- p quasi-bound state with 27 MeV binding energy
Studies with a phenomenological KbarN potential
• A. D., H. Horiuchi, Y. Akaishi and T. Yamazaki, PLB 590, 51 (2004); PRC 70, 044313 (2004)
Systematic study of light kaonic nuclei (3HeK- to 11CK-) with
AMD + G-matrix (effective NN potential ) + AY KbarN potential
shows their interesting properties…
3HeK- … 100MeV binding with a narrow width of 20MeV. (a simple model calculation)
Deeply bound kaonic nuclei !
Kaon'sB.E.
Width(π Y )
Averageddensity
[MeV] [MeV] [fm- 3]ppnK - 110.3 21.2 0.53pppK - 96.7 12.5 0.66pppnK - 105.0 25.9 0.436BeK - 104.2 33.3 0.379BK - 118.5 33.0 0.3311CK - 117.4 46.0 0.36
① Deeply bound and Dense
③ Isovector deformation ④ Proton satellite
pppK-
② Drastic change of structure
8Be 8BeK-
Theoretical studies of nuclear system with anti-kaons
• Medium to heavy nuclei with multi-antikaons
• Nuclear matter with antikoansNeutron star, kaon condensation…
- T. Muto, T. Maruyama and T. Tatsumi, PRC79, 035207 (2009)
- D. Gazda, E. Friedman, A. Gal and J. Mares, PRC76, 055204 (2007); PRC77, 045206 (2008)
• Light nuclei with a single antikaon3HeK- ~ 11CK- studied with AMD + G-matrix + AY potential
E(K) 100MeV≒• Light nuclei with double antikaons
3HeK-K- etc studied with AMD + G-matrix + AY potentialE(2K) 200MeV≒
Studied with Relativistic Mean Field
… Antikaon part is based on non-linear chiral Lagrangian
Strongly repulsive KbarKbar interaction
Saturation for the number of antikaonsIn case of 15O+xK-, central nuclear density and –B/x are saturated for x>8.
2. Variational calculation of K-pp with
a chiral SU(3)-based KbarN potential
Are kaonic nuclei really exotic?
•The phenomenological KbarN potential is all right?
πΣ-πΣ potential is completely neglected, although it is somewhat strongly attractive in chiral SU(3) theory.
KbarN πΣ ηΛ KΞ
Chiral SU(3)AY potential
•The phenomenological KbarN potential is all right?
πΣ-πΣ potential is completely neglected, although it is somewhat strongly attractive in chiral SU(3) theory.
•The G-matrix treatment is adequate?
NN repulsive core is too smoothed out? As a result, such a dense state is formed??
Are kaonic nuclei really exotic?
More theoretical study of the most essential kaonic nucleus
K-pp system “Prototype of kaonic nuclei” studied with
a chiral SU(3)-based KbarN potential
Variational calculation of K-pp with a chiral SU(3)-based KbarN potential
Av18 NN potential … a realistic NN potential with strong repulsive core (3GeV).
A. Doté, T. Hyodo and W. Weise,Nucl. Phys. A804, 197 (2008)Phys. Rev. C79, 014003 (2009)
1E
Strong repulsive core(3 GeV)
Variational calculation of K-pp with a chiral SU(3)-based KbarN potential
Av18 NN potential … a realistic NN potential with strong repulsive core (3GeV).
Effective KbarN potential based on Chiral SU(3) theory… reproduce the original KbarN scattering amplitude obtained with coupled channel chiral dynamics.
Single channel, Energy dependent, Complex, Gaussian-shape potential
A. Doté, T. Hyodo and W. Weise,Nucl. Phys. A804, 197 (2008)Phys. Rev. C79, 014003 (2009)
Local KbarN potential based on Chiral SU(3)
I=0 KbarN scattering amplitude
Chiral unitary; T. Hyodo, S. I. Nam, D. Jido, and A. Hosaka, Phys. Rev. C68, 018201 (2003)
Chiral Unitary
1420
Resonance position in I=0 KbarN channel
In Chiral unitary model,
1420 MeVnot 1405 MeV !
Effective potential
T. Hyodo and W. Weise, PRC77, 035204(2008)
Variational calculation of K-pp with a chiral SU(3)-based KbarN potential
Av18 NN potential … a realistic NN potential with strong repulsive core (3GeV).
Effective KbarN potential based on Chiral SU(3) theory… reproduce the original KbarN scattering amplitude obtained with coupled channel chiral dynamics.
Single channel, Energy dependent, Complex, Gaussian-shape potential
A. Doté, T. Hyodo and W. Weise,Nucl. Phys. A804, 197 (2008)Phys. Rev. C79, 014003 (2009)
I=0 KbarN resonance “Λ(1405)”appears at 1420 MeV, not 1405 MeV
Variational method… Trial wave function contains NN/KbarN correlation functions.
The NN repulsive core can directly be treated.
N N
Kbar
1KNF2KNF
1 2N NF 2( ) ( )expij ij
i jij a aa
F C b r r
0 , 1/ 2, 1/ 20, 0
Z
NN
J T TL S
Variational calculation of K-pp with a chiral SU(3)-based KbarN potential
Av18 NN potential … a realistic NN potential with strong repulsive core (3GeV).
Effective KbarN potential based on Chiral SU(3) theory… reproduce the original KbarN scattering amplitude obtained with coupled channel chiral dynamics.
Single channel, Energy dependent, Complex, Gaussian-shape potential
Four variants of chiral unitary modes 2
N K
N K
M m B Ks
M m B K
×
Total B. E. : 20 ± 3 MeVG ( KbarN→Y ) : 40 ~ 70 MeV
Shallow binding and large decay width
A. Doté, T. Hyodo and W. Weise,Nucl. Phys. A804, 197 (2008)Phys. Rev. C79, 014003 (2009)
I=0 KbarN resonance “Λ(1405)”appears at 1420 MeV, not 1405 MeV
Variational method… Trial wave function contains NN/KbarN correlation functions.
The NN repulsive core can directly be treated.
Structure of K-pp
N N
Kbar
KbarN potential based on “HNJH”“Corrected”, N Ks M m B K
Structure of K-pp
Kbar
2.21 fm
1.97 fm
N N
KbarN potential based on “HNJH”“Corrected”, N Ks M m B K
NN distance in normal nuclei ~ 2 fmSize of deuteron ~ 4 fm
K-pp 中の二核子は普通の原子核の断片!通常核密度に対応していると思える。
Structure of K-pp
Kbar
N N
Mixture of TN=0 component = 3.8 %
KbarN potential based on “HNJH”“Corrected”, N Ks M m B K
NN distance = 2.21 fm KbarN distance = 1.97 fm
1.97 fm
Structure of K-pp
Kbar
N N
Mixture of TN=0 component = 3.8 %
I=0 KbarN
1.82 fm
2 0.4l
KbarN potential based on “HNJH”“Corrected”, N Ks M m B K
NN distance = 2.21 fm KbarN distance = 1.97 fm
Structure of K-pp
Kbar
N N
Mixture of TN=0 component = 3.8 %
I=0 KbarN I=1 KbarN
1.82 fm 2.33 fm
2 0.4l 2 1.9l
KbarN potential based on “HNJH”“Corrected”, N Ks M m B K
NN distance = 2.21 fm KbarN distance = 1.97 fm
Structure of K-pp
N
Mixture of TN=0 component = 3.8 %
I=1 KbarN
2.33 fm
2 1.9l
NN distance = 2.21 fm KbarN distance = 1.97 fm
“Λ(1405)” as I=0 KbarN calculated with this potential
1.86 fm2 0.0l
Kbar
N
KbarN potential based on “HNJH”“Corrected”, N Ks M m B K
I=0 KbarN
1.82 fm2l = 0.4
Almost “Λ(1405)”
Structure of K-ppKbarN potential based on “HNJH”“Corrected”, N Ks M m B K
Density distribution: KbarN pair in K-pp vs “(1405)”
NKbar
“Λ(1405)”
Isospin 0Isospin 0 KbarN pair
Isospin 1 KbarN pair
N
“K-pp ”
Isospin 0 and 1 mixed
N Kbar
“(1405)” almost survives in K-pp!
• Dispersive correction (Effect of imaginary part)
+6 ~ +18 MeV
• p-wave KbarN potential ~ -3 MeV 10 ~ 35 MeV
• Two nucleon absorption 4 ~ 12 MeV
s-wave KbarN potential (Variational calculation)
B .E. Width
20 ± 3 MeV 40 ~ 70 MeV
Rough estimation 20 ~ 40 MeVTotal B .E.
55 ~ 120 MeVTotal Width
K-pp …
Very large…
Variational calculation of K-pp with a chiral SU(3)-based KbarN potential
A. Doté, T. Hyodo and W. Weise,Nucl. Phys. A804, 197 (2008)Phys. Rev. C79, 014003 (2009)
3. Current status of the K-pp study
Kbar nuclei = Exotic system !?To make the situation more clear …
K-pp= Prototye of Kbar nuclei
Studied with various methods, because it is a three-body system:
•Doté, Hyodo, Weise Variational with a chiral SU(3)-based KbarN potential PRC79, 014003(2009)•Akaishi, Yamazaki ATMS with a phenomenological KbarN potential PRC76, 045201(2007)•Ikeda, Sato Faddeev with a chiral SU(3)-derived KbarN potential PRC76, 035203(2007)•Shevchenko, Gal , Faddeev with a phenomenological KbarN potential PRC76, 044004(2007) Mares•Wycech, Green Variational with a phenomenological KbarN potential (with p-wave) PRC79, 014001(2009)
•Arai, Yasui, Oka Λ* nuclei model PTP119, 103(2008) continued by Uchino, Hyodo, Oka•Nishikawa, Kondo Skyrme model PRC77, 055202(2008)
All calculations predict that K-pp can be bound.
Experiments concerned to this topics: FINUDA (Frascatti), KEK, DISTO (Sacley), OBELIX (CERN)Planned or undergoing experiments: FOPI (GSI), J-PARC, AMADEUS (Frascatti)
There are several experiments:
50 60 70 80 90 100 110 120 130
-140
-120
-100
-80
-60
-40
-20
0
Width (KbarNN→πYN) [MeV]
- B.E
. [M
eV]
Doté, Hyodo, Weise [1](Variational, Chiral SU(3))
Akaishi, Yamazaki [2](Variational, Phenomenological)
Exp. : FNUDA [5]if it is a K-pp bound state.
Exp. : DISTO [6]if it is a K-pp bound state.
Using S-wave KbarN potentialconstrained by experimental data. … KbarN scattering data, Kaonic hydrogen atom data, “Λ(1405)” etc.
Ikeda, Sato [4](Faddeev, Chiral SU(3))
Shevchenko, Gal, Mares [3](Faddeev, Phenomenological)
[1] PRC79, 014003 (2009)[2] PRC76, 045201 (2007)[3] PRC76, 044004 (2007)[4] PRC76, 035203 (2007)
[5] PRL94, 212303 (2005)[6] PRL104, 132502 (2010)
Recent results of calculation of K-pp Recent results of calculation of K-pp and related experiments
50 60 70 80 90 100 110 120 130
-140
-120
-100
-80
-60
-40
-20
0
Width (KbarNN→πYN) [MeV]
- B.E
. [M
eV]
Using S-wave KbarN potentialconstrained by experimental data. … KbarN scattering data, Kaonic hydrogen atom data, “Λ(1405)” etc.
Shevchenko, Gal, Mares [3](Faddeev, Phenomenological)
[1] PRC79, 014003 (2009)[2] PRC76, 045201 (2007)[3] PRC76, 044004 (2007)[4] PRC76, 035203 (2007)
[5] PRL94, 212303 (2005)[6] PRL104, 132502 (2010)
Recent results of calculation of K-pp Recent results of calculation of K-pp and related experiments
Akaishi, Yamazaki [2](Variational, Phenomenological)
Ikeda, Sato [4](Faddeev, Chiral SU(3))
Wycech, Green [7](Variational, phenomenological,
P-wave)
[7] PRC79, 014001 (2009)
Including P-wave KbarN potential, and other effects.
Doté, Hyodo, Weise [1](Variational, Chiral SU(3))
Exp. : FNUDA [5]if it is a K-pp bound state.
Exp. : DISTO [6]if it is a K-pp bound state.
Recent results with various calculations of K-pp
B. E. Γ (mesonic) Method KbarN Int.Channels
at final step
DHW 20 ± 3 40 ~ 70 Variational Chiral SU(3) KbarN
AY 47 61 Variational Phenom. KbarN
IS 60 ~ 95 45 ~ 80 Faddeev Chiral SU(3) KbarN, πY (AGS) (Separable)
SGM 50 ~ 70 90 ~ 110 Faddeev Phenom. KbarN, πY (AGS) (Separable)
Exp.FINUDA 115±7 67±14 K- absorption, Λp inv. mass DISTO 103±3±5 118±8±10 p+p→K++Λ+p, Λp inv. mass (Finalized)
All four calculations shown above are constrained by experimental data. … KbarN scattering data, Kaonic hydrogen atom data, “Λ(1405)” etc. Only s-wave KbarN potential is used.
Recent results with various calculations of K-pp
B. E. Γ (mesonic) Method KbarN Int.Channels
at final step
DHW 20 ± 3 40 ~ 70 Variational Chiral SU(3) KbarN
AY 47 61 Variational Phenom. KbarN
IS 60 ~ 95 45 ~ 80 Faddeev Chiral SU(3) KbarN, πY (AGS) (Separable)
SGM 50 ~ 70 90 ~ 110 Faddeev Phenom. KbarN, πY (AGS) (Separable)
DHW vs AY
Difference of the used KbarN interactions.
Comparison of AY potential and Chiral-based potential
AY potential
Weinberg-Tomozawa term derived from Chiral SU(3) effective Lagrangian
KbarN πΣ ηΛ KΞ
Coupled channel Chiral dynamics
• Energy independent potential• No πΣ-πΣ interaction
• Energy dependent potential• Somewhat strongly attractive πΣ-πΣ interaction
Λ(1405) = a quasi-bound state of I=0 KbarN at 1405MeV.
Appears in I=0 KbarN channel.
I=0 KbarN resonance @ 1405MeV.
Two poles (double pole); one couples strongly to KbarN, the other couples strongly to πΣ.
Λ(1405) (experimentally observed) appears in I=0 πΣ-πΣ channel.
I=0 KbarN resonance @ 1420MeV.
I=0 KbarN full scattering amplitude
Almost same in the on-shell region
Quite different in the sub-threhold region
Comparison of AY potential and Chiral-based potential
Recent results with various calculations of K-pp
B. E. Γ (mesonic) Method KbarN Int.Channels
at final step
DHW 20 ± 3 40 ~ 70 Variational Chiral SU(3) KbarN
AY 47 61 Variational Phenom. KbarN
IS 60 ~ 95 45 ~ 80 Faddeev Chiral SU(3) KbarN, πY (AGS) (Separable)
SGM 50 ~ 70 90 ~ 110 Faddeev Phenom. KbarN, πY (AGS) (Separable)
DHW vs AYIn Chiral SU(3) theory, the πΣ-πΣ interaction is so attractive to make a resonance, while AY potential doesn’t have it.
“Λ(1405)” is I=0 KbarN bound state at 1420 MeV or 1405 MeV?
AY potential is twice more attractive than Chiral-based one.
Recent results with various calculations of K-pp
B. E. Γ (mesonic) Method KbarN Int.Channels
at final step
DHW 20 ± 3 40 ~ 70 Variational Chiral SU(3) KbarN
AY 47 61 Variational Phenom. KbarN
IS 60 ~ 95 45 ~ 80 Faddeev Chiral SU(3) KbarN, πY (AGS) (Separable)
SGM 50 ~ 70 90 ~ 110 Faddeev Phenom. KbarN, πY (AGS) (Separable)
DHW vs IS• Separable approximation?• Different energy dependence of interaction kernel Vij?• πΣN three-body dynamics … may not be included in DHW. (Y. Ikeda and T. Sato, PRC79, 035201(2009))
Although both are based on Chiral SU(3) theory, results are very different from each other.
Variational cal. vs FaddeevA possible reason is
πΣN thee-body dynamics
In the variational calculation (DHW), πΣ channel is eliminated and incorporated into the effective KbarN potential.
Y. Ikeda and T. Sato, PRC79, 035201(2009)
Three-body system calculated with the effective KbarN potential
Σ Σ
K
N+ …
…=
πK
N
πK
N
K
N
N N N NN N
barK NNE
conserved
4. Experiments related to Kbar nuclear
physics
K原子核に関係する実験
• LEPS / SPring-8
πΣ invariant mass 測定
K原子 (Kaonic atom)
Λ(1405)
• CLAS / JLab
• Kaonic 4He atom, 2p レベルシフト (3d→2p X 線測定 ) @ KEK (E570) S. Okada et. al., Phys. Lett. B653, 387 (2007)
• Kaonic hydrogen atom, 1s レベルシフト @ DEAR group, DAΦNE, G. Beer et al., Phys. Rev. Lett. 94, 212302 (2005) Frascati National Laboratories
• Kaonic hydrogen, deuterium @ SIDDHARTA group
• Kaonic 3He atom, 2p レベルシフト (3d→2p X 線測定 ) @ J-PARC (E17, DAY-1)
γ + p → K+ + Λ(1405), Λ(1405) → π Σ
K. Moriya and R. Schumacher, Nucl. Phys. A835, 325 (2010)J. K. Ahn, Nucl. Phys. A835, 329 (2010)
π-Σ+, π0Σ0, π+Σ- が全て押さえられた
M. Bazzi et al., Phys. Lett. B704, 113 (2011)
K原子核に関係する実験
• LEPS / SPring-8
πΣ invariant mass 測定
K原子 (Kaonic atom)
Λ(1405)
• CLAS / JLab
• Kaonic 4He atom, 2p レベルシフト (3d→2p X 線測定 ) @ KEK (E570) S. Okada et. al., Phys. Lett. B653, 387 (2007)
• Kaonic hydrogen atom, 1s レベルシフト @ DEAR group, DAΦNE, G. Beer et al., Phys. Rev. Lett. 94, 212302 (2005) Frascati National Laboratories
• Kaonic hydrogen, deuterium @ SIDDHARTA group
• Kaonic 3He atom, 2p レベルシフト (3d→2p X 線測定 ) @ J-PARC (E17, DAY-1)
γ + p → K+ + Λ(1405), Λ(1405) → π Σ
K. Moriya and R. Schumacher, Nucl. Phys. A835, 325 (2010)J. K. Ahn, Nucl. Phys. A835, 329 (2010)
π-Σ+, π0Σ0, π+Σ- が全て押さえられた
M. Bazzi et al., Phys. Lett. B704, 113 (2011)
DEAR exp. for kaonic hydrogen atom
シフトの符号は同じだが、KEKの前回の実験(KpX)と重ならない!
Kaonic hydrogen atom, 1s のレベルシフト @ DEAR Collaboration, DAΦNE, Frascati National Laboratories
G. Beer et al., Phys. Rev. Lett. 94, 212302 (2005)
cf) KEK exp. M.Iwasaki et al., Phys. Rev. Lett. 78, 3067 (1997)
B. Borasoy et al., Phys. Rev. Lett. 94, 213401 (2005)
KEK exp.
DEARCoupled channel chiral dynamics (Chiral unitary model) でDEAR の結果を合わすのには苦労する。かろうじてギリギリ合わせられる程度。。。
SHIDDARTA exp. for kaonic hydrogen atom
KEK 実験(KpX)とコンシステントな結果
Kaonic hydrogen atom, 1s のレベルシフト @ SHIDDARTA Collaboration, DAΦNE, Frascati National Laboratories
M. Bazzi et al., Phys. Lett. B704, 113 (2011)
K-p 散乱長が精密に決定
理論計算にとって重要なインプットに強い拘束条件
KbarN subthreshold での散乱振幅の振る舞い、Λ(1405) のポールの位置、が制限される。
Y. Ikeda, T. Hyodo and W. Weise, Phys. Lett. B706, 63 (2011)
K原子核に関係する実験
• LEPS / SPring-8
πΣ invariant mass 測定
K原子 (Kaonic atom)
Λ(1405)
• CLAS / JLab
• Kaonic 4He atom, 2p レベルシフト (3d→2p X 線測定 ) @ KEK (E570) S. Okada et. al., Phys. Lett. B653, 387 (2007)
• Kaonic hydrogen atom, 1s レベルシフト @ DEAR group, DAΦNE, G. Beer et al., Phys. Rev. Lett. 94, 212302 (2005) Frascati National Laboratories
• Kaonic hydrogen, deuterium @ SIDDHARTA group
• Kaonic 3He atom, 2p レベルシフト (3d→2p X 線測定 ) @ J-PARC (E17, DAY-1)
γ + p → K+ + Λ(1405), Λ(1405) → π Σ
K. Moriya and R. Schumacher, Nucl. Phys. A835, 325 (2010)J. K. Ahn, Nucl. Phys. A835, 329 (2010)
π-Σ+, π0Σ0, π+Σ- が全て押さえられた
M. Bazzi et al., Phys. Lett. B704, 113 (2011)
KEK E570 for kaonic 4He atom
シフトは 0 eV と consisitent
Kaonic 4He atom, 2p のレベルシフト 3d→2p X 線測定 @ KEK, E570
理論の予言がほぼ 0eV に対して、過去の実験ではシフトは平均 -43 eV
“Kaonic helium puzzle”
S. Okada et. al., Phys. Lett. B653, 387 (2007)
パズルは解けた!S. Hirenzaki et al., Phys. Rev. C61, 055205 (2000)
J-PARC for kaonic 3He atomKaonic 3He atom, 2p のレベルシフト 3d→2p X 線測定 @ J-PARC, E17 DAY-1
S. Okada et. al., Phys. Lett. B653, 387 (2007)
Kaonic 4He atom, 2p のレベルシフト … ほぼ 0 eV と確定
赤石氏の計算
KbarN potentialの強度が二つの領域に絞られた。
+さらに 3Heでシフトが測定されることでKbarN potentialの強度に絞りを掛けることが期待できる。
Y. Akaishi, Proceedings of EXA’05, Austrian Academy of Sciences press, Vienna, 2005, p.45
※ 特定領域研究「ストレンジネスで探るクォーク多体系」研究会 2007 での岡田氏のスライドより引用
K原子核に関係する実験
• LEPS / SPring-8
πΣ invariant mass 測定
K原子 (Kaonic atom)
Λ(1405)
• CLAS / JLab
• Kaonic 4He atom, 2p レベルシフト (3d→2p X 線測定 ) @ KEK (E570) S. Okada et. al., Phys. Lett. B653, 387 (2007)
• Kaonic hydrogen atom, 1s レベルシフト @ DEAR group, DAΦNE, G. Beer et al., Phys. Rev. Lett. 94, 212302 (2005) Frascati National Laboratories
• Kaonic hydrogen, deuterium @ SIDDHARTA group
• Kaonic 3He atom, 2p レベルシフト (3d→2p X 線測定 ) @ J-PARC (E17, DAY-1)
γ + p → K+ + Λ(1405), Λ(1405) → π Σ
K. Moriya and R. Schumacher, Nucl. Phys. A835, 325 (2010)J. K. Ahn, Nucl. Phys. A835, 329 (2010)
π-Σ+, π0Σ0, π+Σ- が全て押さえられた
M. Bazzi et al., Phys. Lett. B704, 113 (2011)
Λ(1405) - πΣ invariant mass 測定 -
三つの異なる電荷状態が抑えられた
•LEPS / Spring-8K. Moriya and R. Schumacher, Nucl. Phys. A835, 325 (2010)
• CLAS / Jefferson Laboratory
γ + p → K+ + Λ(1405), Λ(1405) → π Σ
ピークの順番が理論(chiral unitary) と違う?
Highest peak実験: Σ+ π-
理論: Σ- π+
理論
J. K. Ahn, Nucl. Phys. A835, 329 (2010)
p (γ, K+ π) Σ at Eγ = 1.5-2.4GeVCharged πΣ を測定
Experiments for
K-pp search
K原子核に関係する実験 K原子核 (Kaonic nuclei)
• K- absorption on various targets / Invariant mass Λp @ FINUDA collaboration, DAΦNE, Frascati National Laboratories M. Angello et. al., Phys. Rev. Lett. 94, 212303 (2005)
• Heavy ion collision (?+?) / Invariant mass Λp @ FOPI group, GSI N. Herrmann, Proc. of EXA’05, Austrian Academy of Sciences Press, (2005), p73
• Anti-proton annihilation on 4He / Invariant mass Λp @ OBELIX group, CERN G. Bendiscioli et. al., Nucl. Phys. A789, 222 (2007)
• p+p -> K+ + Λ + p / Invariant mass Λp @ DISTO group, SATURNE, Saclay T. Yamazaki et. al., Phys. Rev. Lett. 104, 132502 (2010)
K-pp search
K-ppn search
Search for heavier kaonic nuclei
• 16O (in-flight K-, n) 15OK- / Missing mass @ AGS, BNL T. Kishimoto et. al., Nucl. Phys. A754, 383 (2005)• 12C (in-flight K-, n or p) / Missing mass @ KEK-E548 T. Kishimoto et. al., Prog. Theor. Phys. Suppl. 168, 573 (2007)
• 4He (Stopped K-, n), 4He (Stopped K-, p) / Mssing mass @ KEK-E471, E549 M. Sato et. al., Phys. Lett. B659, 107 (2008), H. Yim et. al., Phys. Lett. B688, 43 (2010)
K原子核に関係する実験 K原子核 (Kaonic nuclei)
• K- absorption on various targets / Invariant mass Λp @ FINUDA collaboration, DAΦNE, Frascati National Laboratories M. Angello et. al., Phys. Rev. Lett. 94, 212303 (2005)
• Heavy ion collision (?+?) / Invariant mass Λp @ FOPI group, GSI N. Herrmann, Proc. of EXA’05, Austrian Academy of Sciences Press, (2005), p73
• Anti-proton annihilation on 4He / Invariant mass Λp @ OBELIX group, CERN G. Bendiscioli et. al., Nucl. Phys. A789, 222 (2007)
• p+p -> K+ + Λ + p / Invariant mass Λp @ DISTO group, SATURNE, Saclay T. Yamazaki et. al., Phys. Rev. Lett. 104, 132502 (2010)
K-pp search
K-ppn search
Search for heavier kaonic nuclei
• 16O (in-flight K-, n) 15OK- / Missing mass @ AGS, BNL T. Kishimoto et. al., Nucl. Phys. A754, 383 (2005)• 12C (in-flight K-, n or p) / Missing mass @ KEK-E548 T. Kishimoto et. al., Prog. Theor. Phys. Suppl. 168, 573 (2007)
• 4He (Stopped K-, n), 4He (Stopped K-, p) / Mssing mass @ KEK-E471, E549 M. Sato et. al., Phys. Lett. B659, 107 (2008), H. Yim et. al., Phys. Lett. B688, 43 (2010)
• FINUDA collaboration (DAΦNE, Frascatti)
Experiments related to K-pp
• K- absorption at rest on various nuclei (6Li, 7Li, 12C, 27Al, 51V)• Invariant-mass method
Strong correlation between emitted p and Λ (back-to-back)
Invariant mass of p and Λ
K-pp
p
Λ
If it is K-pp, …Total binding energy = 115 MeVDecay width = 67 MeV
PRL 94, 212303 (2005)
6 35 4
14 211 3
• Re-analysis of KEK-PS E549
• DISTO collaboration
- p + p -> K+ + Λ + p @ 2.85GeV- Λp invariant mass- Comparison with simulation data
T. Yamazaki et al. (DISTIO collaboration), PRL104, 132502 (2010)
- K- stopped on 4He target- Λp invariant mass
T. Suzuki et al (KEK-PS E549 collaboration), arXiv:0711.4943v1[nucl-ex]
K- pp???B. E.= 103 ±3 ±5 MeVΓ = 118 ±8 ±10 MeV
Strong Λp back-to-back correlation is confirmed.Unknown strength is there in the same energy region as FINUDA.
Experiments related to K-pp
What is the object observed experimentally?
A bound state of K-pp, or another object such as πΣN ???
Only what we can say from only this spectrum is that“There is some object with B=2, S=-1, charge=+1”…
• DISTO collaboration
J-PARC will give us lots of interesting data!
E15: A search for deeply bound kaonic nuclear states by 3He(inflight K-, n) reaction --- Spokespersons: M. Iwasaki (RIKEN), T. Nagae (Kyoto)
E17: Precision spectroscopy of kaonic 3He atom 3d→2p X-rays --- Spokespersons: R. Hayano (Tokyo), H. Outa (Riken)
J-PARC will give us lots of interesting data!
E15: A search for deeply bound kaonic nuclear states by 3He(inflight K-, n) reaction --- Spokespersons: M. Iwasaki (RIKEN), T. Nagae (Kyoto)
E17: Precision spectroscopy of kaonic 3He atom 3d→2p X-rays --- Spokespersons: R. Hayano (Tokyo), H. Outa (Riken)
Dr. Fujioka’s talk (KEK workshop, 7-9. Aug. 08)
at K1.8BR beam line
1.8GeV/c
J-PARC will give us lots of interesting data!
E15: A search for deeply bound kaonic nuclear states by 3He(inflight K-, n) reaction --- Spokespersons: M. Iwasaki (RIKEN), T. Nagae (Kyoto)
E17: Precision spectroscopy of kaonic 3He atom 3d→2p X-rays --- Spokespersons: R. Hayano (Tokyo), H. Outa (Riken)
Missing mass spectroscopy
Dr. Fujioka’s talk (KEK workshop, 7-9. Aug. 08)
All emitted particles will be measured. 「完全実験」
at K1.8BR beam line
1.8GeV/c
Invariant mass spectroscopy
Preceding E15, E27 experiment will be performed in June.
E27: d (π+, K+) K-pp at K1.8 beam line Missing mass measured.
d
π+ K+
Λ(1405)n
p ppK-
5. Summary and
Future plan
5. SummaryKaonic nuclei are exotic system !?
Variational calc. of K-pp with a chiral SU(3)-based KbarN pot.
• B. E. =20±3 MeV, Γ(KbarNN → πYN) = 40 – 70MeV• With p-wave KbarN pot., dispersion correction, and two-nucleon absorption, B. E. =20 – 40 MeV, Γ = 55 – 120MeV
• AMD calculation with G-matrix method using a phenomenological KbarN potential (AY potential) shows that kaonic nuclei may have lots of interesting properties:
Deeply bound and narrow widthdense system with interesting structure…
• Kaonic nuclei are another form of nuclear system involving strangeness. They might be exotic system because of the strong attraction of I=0 KbarN potential.
• However, these properties have not been established and there are some questions.
• Two protons distance = 2.0fm ≒NN mean distance of normal nucleus• Λ(1405) structure (correlation) remains in K-pp.
K-pp is a shallowly bound and not so dense system.
5. SummaryCurrent status of studies of K-pp
The most essential Kbar nuclei “K-pp” (KbarNN, Jp=1/2-, T=0) has been investigated in various ways. But the situation is still controversial…
TheoryVariational + Phenom. KbarN B.E. = 47MeV, Γ= 61MeV PRC76, 045201(2007)
Variational + Chiral-based KbarN B.E. = 20±3MeV, Γ= 40 ~ 70MeV PRC79, 014003(2009)Faddeev + Phenom. KbarN B.E. = 50 ~ 70MeV, Γ= ~ 100MeV PRC76, 044004(2007)Faddeev + Chiral-based KbarN B.E. = 60 ~ 95MeV, Γ= 45 ~ 80MeV PRC76, 035203(2007)
Experiment (Unknown object which seems related to K-pp)FINUDA B.E. = 115MeV, Γ= 67MeV PRL94, 212303(2005)DISTO B.E. = 103MeV, Γ= 118MeV PRL104, 132502 (2010)
Discrepancy between theoretical studies of K-pp• DHW (Variational with Chiral-based) vs AY (Variational with phenomenological) … Difference of KbarN attraction Λ(1420) scheme and Λ(1405) scheme
• DHW (Variational with Chiral-based) vs IS (Faddeev with Chiral-based) … πΣN three-body dynamics (might be also different energy dependence of interaction kernel? )
5. Future plan
• The signal position of DISTO experiment … very close to π+Σ+N threshold
• πΣN dynamics as pointed out by Dr. Ikeda and Prof.Sato.
Direct treatment of πΣN degree in K-pp. Deal with a resonant state, based on variational scheme.
Studied with coupled-channel Complex Scaling Method
Go to charm sector!
K- (subar) D0 (cubar) 494 MeV 1870 MeV
Do D-mesic nuclei existsuch as DNN analog to KbarNN???
M. Bayar, C. W. Xiao, T. Hyodo, A. Dote, M. Oka, E. Oset, arXiv:1205.2275 [hep-ph]
Thank you for your attention!
http://www-conf.kek.jp/hadron1/JPARC-hadsalon/
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