ニュートリノ原子核反応

佐藤　透 ( 阪大　理 )

JPARC Dec. 18 2011

Our previous works on neutrino reaction

single pion production(Delta region) nuclear coherent pion production

Plan

neutrino induced meson production (W<2GeV) trial : inverse transformation

Neutrino induced pion production

Dynamical model of pion production in Delta_33 region

Pion electroproduction Structure functions (data CLAS from C. Smith,2004)

Jones et al. (89) CERN

Kitagaki et al. (90) BNLBarish et al.(79) ANL

Sealock et al.(89)

QE

Pion production

Our amplitudes are available in

Adler-CGLN amplitude

structure functions R(Q^2,W)

? home page for amplitudes and …. ??

Nuclear effects in resonance region

Pion-nucleus interaction elastic scattering

Pion absorption total, inelastic, absorption cross section

Medium effect on pion production, propagation of delta in nuclei Coherent photo pion production, inelastic pion scattering

Neutrino induced coherent pion production

(exclusive reaction, bound final nucleus)

Delta-hole model

Our model of coherent pion production

Non-res res

use t-matrix from dynamical model of piN and weak pion production for both transition operator and pi-Nucleus optical potential

medium modification of pion production mechanism

final state interaction: optical potential

prediction of coherent pion photoproduction

Without medium effect on delta-hole propagator/ FSI of pion

Full

Only Delta for pion production operator

CCpi+

NCpi0

Alvarez-Ruso et al.(07)

Hernandez et. al(10)

Nakamura et al.(10)

Berger Sehgal(09)

CCpi+(K2K) 10.8/5.7 6.1+/-1.3 6.3 0.62x12

NCpi0(MiniBooNE) 5.0/2.6 2.6+/-0.5 2.8

( Kurimoto et al. PRD81(10) )

Flux averaged cross section

agreement among recent theoretical results pi+/pi0 ration ~ 2 due to Delta_33 dominance

* pion momentum distribution, angular distribution• neutrino energy dependence• …are available

data :PRC81 055213

F2 Model available for vector current , W<2GeV

Coupled-channel model of Excited BaryonAnalysis Cener(EBAC)

with extension for axial current fill gap between QE and DIS

Data: hep-ph/0309052

Increasing importance of 2pion production above delta

beyond Delta_33 (N*,Delta region) and DIS

Figure: E. Pasyuk’s talk at Hall-B/EBAC meeting

Single pion electroproduction (Q2 > 0)

Fit to the structure function data (~ 20000) from CLAS

Julia-Diaz, Kamano, Lee, Matsuyama, Sato, Suzuki, PRC80 025207 (2009)

p (e,e’ p0) p

W < 1.6 GeV

Q2 < 1.5 (GeV/c)2

is determined

at each Q2.

N*N

g(q2 = -Q2)q

N-N* e.m. transitionform factor

• Current neutrino reaction model : Delta_33 region (Sato,Uno,Lee) electroproduction model W< 2GeV (EBAC)

• Extend to N* region ANN* coupling from piNN* using PCAC

• Interest for transition (N* <-> DIS) region

Reconstruct from Quasi-elastic scattering

true only for reaction on free nucleon

Can we separate QE?

FSI

+ + …

2

ISI

‘QE’

Quantum mechanical interference among various amplitudes

Simple exercise (Inverse problem)

Extract from

Method : MEM

Assume reliable calculation available

example

energy transfer

spatial momentum transfer

excited states(‘bound’)Giant resonance

Delta_33, pion production

quasi-elastic (QE)

nuclear excitation, Quasi-Elastic, Resonance, Deep Inelastic