N* spectroscopy with meson photoproduction reactions Hiroyuki
Kamano (RCNP, Osaka U.) ELPHGeV Feb. 20-21, 2014 Collaborators
T.-S. H. Lee Argonne Natl. Lab. S.X. Nakamura Osaka U. T. Sato
Osaka U. Slide 2 Baryons PDG (2012): http://pdg.lbl.gov qqq (I=1/2)
[q = u or d] qqq (I=3/2) [q = u or d] qqs (I=0) [q = u or d] qqs
(I=1) [q = u or d] qss (I=1/2) [q = u or d] sss (I=0) qqc (I=0) [q
= u or d] qqc (I=1) [q = u or d] qsc (I=1/2) [q = u or d] ssc (I=0)
qcc (I=1/2) [q = u or d] qqb (I=0) [q = u or d] ssb (I=0) qsb
(I=1/2) [q = u or d] qqb (I=1) [q = u or d] Isospin Baryon
Spectroscopy: Understanding nature of baryons and their excitations
Mass, width, spin, parity ? Internal structure? How produced in
reaction processes? How interact with other particles? Slide 3
Meson photoproduction reactions in N*, * resonance region p
reaction total cross section in N* * region Database is provided by
Kanda-san -region Region our model covers N... J e.m. N*, * N, N, N
K, K, N, Study electromagnetic interactions of N* * Used also for
establishing N*, * mass spectrum and searching for new N*, *
resonances Slide 4 Approaches to N* spectroscopy JLab, ELSA, MAMI,
SPring-8, ELPH, Mass, width, form factors, etc of N* & *
QCDQCDQCDQCD Lattice QCD QCD-inspired Hadron Models Analysis based
on reaction theory Reaction Data Multichannel unitary condition:
ANL-Osaka/EBAC-JLab, Bonn-Gatchina, Carnegie Mellon-Berkely,
Dubna-Mainz-Taipei, VPI/GWUGeorge, Giessen, Juelich,
Karlsruhe-Helsinki, N* spectroscopy with multichannel unitary
reaction models has made a significant progress. Ensures
conservation of probability. Defines analytic structure (branch
points, cuts) of the amplitudes in complex-E plane. Our approach !!
Constituent quark models Soliton models Holographic QCD etc
Constituent quark models Soliton models Holographic QCD etc Slide 5
Unitary multichannel reaction model channel coupling effect
Dynamical coupled-channels model [Matsuyama, Sato, Lee, Phys. Rep.
439(2007)193] V NN NN NN KK NN e.g. N scattering Summing up all
possible transitions between reaction channels in the intermediate
processes !! Slide 6 ANL-Osaka dynamical coupled-channels analysis
of meson production reactions Exchange potential Exchange potential
Bare N* states Transition potential N N, s-channel u-channel
t-channelcontact Exchange potentials Bare N* states N* bare Bare N*
states Corresponding to N* states defined in static hadron models
excluding meson-baryon continuums bare N* Formation of hadron
resonances core(bare) meson cloud meson baryon Physical N*s will be
a mixture of the two pictures: Slide 7 Extraction of baryon
resonances via comprehensive analysis of meson production reactions
PDG 4* PDG 3* Ours Mass spectrum Decay width Construct the reaction
model by making a comprehensive analysis of N N, N, N, K, K, N, (*)
N N, N, N, K, K, N, Making analytic continuation of amplitudes to
complex E-plane (Suzuki, Sato, Lee PRC79(2009)025205;
PRC82(2010)045206) mass width pole posiiton coupling constants
(residues) 1/2 at the pole poles of amplitude = baryon resonance!!
+ p K + + DCS P Slide 8 Our analyses of meson production reactions
p N p N p N p p p K , p K + K 2006 2009 (EBAC/JLab) 6 channels ( N,
N, N, , N, N) < 2 GeV < 1.6 GeV < 2 GeV 2010 2013
(ANL-Osaka) 8 channels ( N, N, N, , N, N,K ,K ) < 2.3 GeV <
2.1 GeV # of coupled channels Fully combined analysis of N, N N, N,
K , K reactions !! HK, Nakamura, Lee, Sato PRC88 (2013) 035209
Julia-Diaz, Lee, Matsuyama, Sato, PRC76 (2007) 065201; Julia-Diaz,
et al., PRC77 (2008) 045205 Slide 9 Database for ANL-Osaka DCC
analysis 22,348 data of unpolarized & polarized observables to
fit !! N N PWA from SAIDp N, K, K observables p N, p, K, K
observables HK, Nakamura, Lee, Sato PRC88 (2013) 035209 unpolarized
diff. crs. sec. single pol. beam-target beam-recoil target-recoil
Pseudoscalar meson photoproductions have 1 + 15 observables !!
(Over-) complete experiments has been achieved by CLAS for K and K
photoproductions !!! Slide 10 p 0 p reaction 8ch DCC-analysis [HK,
Nakamura, Lee, Sato, PRC88 (2013) 035209] previous 6ch DCC-analysis
(fitted to N N data only up to W = 1.6 GeV) [Julia-Diaz et al.,
PRC77 (2008) 045205] 1.6 GeV1.9 GeV Differential cross section (W =
1.08-2.1 GeV) Slide 11 p 0 p reaction (2/3) Note: In computing
polarization obs. of pseudoscalar-meson photoproductions, we
followed convention defined in Sandorfi, Hoblit, Kamano, Lee, J.
Phys. G38 (2011) 053001. (See arXiv:1108.5411 for comparison of
conventions used in different analysis groups.) Slide 12 p 0 p
reaction (3/3) T G P H hat E 8ch DCC-analysis [HK, Nakamura, Lee,
Sato, PRC88 (2013) 035209] Slide 13 Mass spectrum Slide 14 Q 2 :
small Q 2 : large bare baryon meson clouds meson baryon How
effective d.o.f.s describing baryon change with Q 2 ? N*, * N (q 2
= -Q 2 ) q N-N* electromagnetic transition form facctor hadronic
picture partonic picture Transition form factors and baryon
structure Measurement of p(e,e)N & p(e,e)N for 5 < Q 2 <
10 (GeV/c) 2. JLab CLAS12 experiment (E12-09-003) * N e N*, * e
Slide 15 Full Bare Julia-Diaz et al, PRC75 015205 (2007) N (1232)
M1 transition form factor Alexandrou et al., PRD83 (2011) 014501
Lattice QCD Tiator et al., EPJST 198 (2011) 141 Transverse
(transition) charge densities proton proton proton N*(1440)[Roper
resonance] b x [fm] b y [fm] unpolarized density polarized in
x-dir. (1232) at low Q 2 light charge dark or charge Transition
form factors and baryon structure Slide 16 Establish N*, * spectrum
in s 1/2 = 1450 - 1750 MeV The data we expect: What we expect ELPH?
(1600) 3/2 + : Roper-like state of baryon mass is still uncertain
(1450-1700 MeV) N(1685) ? ? : Seen in d (n) p New N*, * could exist
behind large N* (1535) 1/2 - N*(1650) 1/2 - N*(1520) 3/2 -
resonances !! (Many channels open in 1.6-1.7 GeV region) Double
meson productions & Deuteron(neutron) target reactions N (~
1220 MeV) N(~ 1620 MeV) N (~ 1490 MeV) K (~ 1610 MeV) K (~ 1680
MeV) N (~ 1720 MeV) Slide 17 Our tasks Reducing computing time
Extension to deuteron-target reactions Computing time for double
meson productions Computing time for single meson productions =
O(10 1 ) , , K, , d + Computation of cross section O(10 6 -10 7 )
times are needed in 2 -fitting. Slide 18 n - p d/d T P VERY
PRELIMINARY !! Slide 19 n 0 n VERY PRELIMINARY !! d/d Slide 20 n n
d/d VERY PRELIMINARY !! Slide 21 Predicted results for n K 0
Sensitive to F17 wave? ALL observables @ W = 1.8 GeV VERY
PRELIMINARY !! Slide 22 Double-pion production cross sections
(current situation) N N , N N , N,N N , N N , N 8ch. model [HK,
PRC88 (2013) 045208] 6ch. model [HK, Julia-Diaz, Lee, Matsuyama,
Sato, PRC79 (2008) 025206] Predicted p N cross sections Slide 23
8ch. model [HK, Nakamura, Lee, Sato PRC88 (2013) 035209] 6ch. model
[HK, Julia-Diaz, Lee, Matsuyama, Sato, PRC80 (2009) 065203]
Predicted p N cross sections N , N,N N , N N , N Double-pion
production cross sections (current situation) Slide 24 Establish
high-mass N*, * mass spectrum The data we expect & our tasks
What we expect LEPS/LEPS2 ? Poorly established Very large width
Approaches based on reaction theory will become more important. In
the future, we aim at establishing N*, * spectrum up to s 1/2 = 2.5
GeV that can access with LEPS/LEPS2. Differential cross section and
polarizations of N N, N, K*Y, K*, Our tasks Reducing computation
time treatment of 4-body channel N channel Slide 25 meson
productions with electron beam ?? Other topics e+d reactions are
necessary for extracting Q2 dependence of neutron target n-N*
transition form factors. DIS region QE region RES region CP phase
& mass hierarchy studies with atmospheric exp. T2K Construction
of unified neutrino reaction model describing overlapping regions
between QE, RES, and DIS regions !! Y. Hayato (ICRR, U. of Tokyo),
M. Hirai (Tokyo U. of Sci.) H. Kamano (RCNP, Osaka U.), S. Kumano
(KEK) S. Nakamura (YITP, Kyoto U.), K. Saito (Tokyo U. of Sci.) M.
Sakuda (Okayama U.), T. Sato (Osaka U.) [ arXiv:1303.6032]
Transition form factors are crucial not only for N* structure
study, but also for neutrino-induced reactions !!
Collaboration@J-PARC Branch of KEK Theory Center & C02
http://nuint.kek.jp Slide 26 back up Slide 27 p + n reaction (1/3)
DCS 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209]
Slide 28 p + n reaction (2/3) PT 8ch DCC-analysis [HK, Nakamura,
Lee, Sato, PRC88 (2013) 035209] Slide 29 p + n reaction (3/3) hat
EG H 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013)
035209] Slide 30 p p reaction (1/2) DCS 8ch DCC-analysis [HK,
Nakamura, Lee, Sato, PRC88 (2013) 035209] Slide 31 p p reaction
(2/2) T 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013)
035209] Slide 32 p K + reaction (1/2) DCS P 8ch DCC-analysis [HK,
Nakamura, Lee, Sato, PRC88 (2013) 035209] Slide 33 p K + reaction
(2/2) T Ox Oz Cx Cz 8ch DCC-analysis [HK, Nakamura, Lee, Sato,
PRC88 (2013) 035209] Slide 34 p K + 0 reaction DCS P Cx Cz 8ch
DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] Slide
35 p K 0 + reaction DCS P 8ch DCC-analysis [HK, Nakamura, Lee,
Sato, PRC88 (2013) 035209] Slide 36
