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Photoproduction of K* for the study of L (1405). Tetsuo Hyodo a. Hosaka a , M. J. Vicente Vacas b and E. Oset b. a RCNP , Osaka b IFIC, Valencia. Special thanks to Prof. Morimatsu. 2004, January 30th. Contents. Chiral unitary model Motivation : Two poles? - PowerPoint PPT Presentation
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Photoproduction of Photoproduction of K*K* for the for the study of study of (1405)(1405)
Photoproduction of Photoproduction of K*K* for the for the study of study of (1405)(1405)
Tetsuo Hyodoa
a RCNP, Osaka b IFIC, Valencia
2004, January 30th
A. Hosakaa, M. J. Vicente Vacasb and E. Osetb
Special thanks to Prof. Morimatsu
ContentsContents
1. Chiral unitary model1. Motivation : Two poles?2. Framework of the chiral unitary model3. Example : Kp scatterings4. Pole structure of (1405)
2. K*(1405) production1. Advantage of the reaction2. Effective interactions3. Numerical results4. Summary and conclusions
Motivation : Two poles?Motivation : Two poles?
• Cloudy bag model (1990) J. Fink et al. PRC41, 2720
• Chiral unitary model (2001~) J. A. Oller et al. PLB500, 263 E. Oset et al. PLB527, 99 D. Jido et al. PRC66, 025203 T. Hyodo et al. PRC68, 018201
There are two poles of the scattering amplitudearound nominal (1405) energy region.
(1405) : JP=1/2, I=0
ChU model, T. Hyodo
Chiral unitary modelChiral unitary model
Unitarity of S-matrixChiral symmetry
Flavor SU(3) meson-baryon scatterings (s-wave)
Resonances
Low energy behavior
Non-perturbativeresummation
(1405), (1670), N(1535),(1620), (1620)
Dynamicalgeneration
Chiral perturbation theory
Unitarization
Framework of the chiral unitary modelFramework of the chiral unitary model
Resonances
Generated resonances areexpressed as poles of the scattering amplitude.
Total cross sections of Kp scatteringsTotal cross sections of Kp scatterings
T. Hyodo, et al., Phys. Rev. C 68, 018201 (2003)
200
150
100
50
0300200100
K-p
70
60
50
40
30
20
10
0300200100
π0
200
150
100
50
0300200100
π+−
60
50
40
30
20
10
0300200100
Plab [ / ]MeV c
K0n
60
50
40
30
20
10
0300200100
Plab [ / ]MeV c
π0080
60
40
20
0300200100
Plab [ / ]MeV c
π−+
Poles of amplitude in S=1 channelPoles of amplitude in S=1 channel
D. Jido, et al., Nucl. Phys. A 723, 205 (2003)
8×8 ~ 1,8,8,10,10,27attractive repulsive
(1405) in the chiral unitary model(1405) in the chiral unitary model
D. Jido, et al., Nucl. Phys. A 723, 205 (2003)
π mass distribution
1390 + 66i (π
1426 + 16i (KN)
Photoproduction of K* (1405)Photoproduction of K* (1405)
Only Kp channel appears at the initial stage
Higher pole ??
Advantage of this reactionAdvantage of this reaction
With polarized photon beam, the exchangedparticle can be identified.
Clear mechanism
Effective interactions for vector mesonEffective interactions for vector meson
1. VP coupling
2. VPP coupling
3. (1385)MB coupling
4. Form factor
Effective interaction for baryon resonanceEffective interaction for baryon resonance
ChU amplitude
(1385) pole term
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0300028002600240022002000
[ ]s MeV
π00 ( =0)I π+-
π-+
π0 ( =1)I
(1405)*KKππ
Total cross sectionTotal cross section
4
3
2
1
015001450140013501300
MI [ ]MeV
π00 ( =0)I π+-
π-+
π0 ( =1)I
nvariant mass distributionnvariant mass distribution
Plab = 2.5 GeV/csqrt s ~ 2.35 GeV
Isospin decomposition of π statesIsospin decomposition of π states
• Difference among charged states -> when summed up, this term vanishes
• No p-wave contribution -> I=1 s-wave amplitude
4
3
2
1
015001450140013501300
MI [ ]MeV
π00 ( =0)I π+-
π-+
π0 ( =1)I
( π+- + π-+ ) / 2
nvariant mass distribution 2nvariant mass distribution 2
Plab = 2.5 GeV/csqrt s ~ 2.35 GeV
I=1, s-wave amplitdueI=1, s-wave amplitdue
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
15001450140013501300MI [ ]MeV
π+- − π-+
π ( =1)I
Summary and conclusions 1Summary and conclusions 1
We study the structure of (1405) using the chiral unitary model.
� There are two poles of the scattering amplitude around nominal (1405).
Pole 1 (1426+16i) : strongly couples to KN statePole 2 (1390+66i) : strongly couples to π state
� By observing the charged π states in the p -> K*(1405) reaction, it is possible to isolate higher energy pole.
Summary and conclusions 2Summary and conclusions 2
� If we observe neutral π state, clear I=0 distribution is obtained.
� Combining three π states, we can also study the s-wave I=1 amplitude, where the existence of another pole is argued.
T. Hyodo, et al, nucl-th/0401051
http://www.rcnp.osaka-u.ac.jp/~hyodo/
Appendix : other processesAppendix : other processes
p -> Kπ
p -> πJ.C. Nacher, et al., PLB461, 299(1999)
J.C. Nacher, et al., PLB445, 55(1999)