Incoherent -mesons photoproduction from deuterons

LEPS meetingWen-Chen Chang05/01/2008

Outline

Physics motivation. Confusion on the normalization. Updated plots.

LEPS AX T. Ishikawa et al. Physics Letters B 608 (2005) 215–222

VMD calculation from pp:p=12-13 mb

P. Mühlich, U. Mosel / Nuclear Physics A 765 (2006) 188–196

Model calculation includes:•Fermi motion•Pauli blocking•Nuclear shadowing•Quasi elastic scattering•Pauli blocking

Nuclear density effect?

Conclusion from theoretical studies: a large inelastic N cross section is required to explain the strong attenuation of flux from nuclei beyond standard scenario.

The modification of self energy of in finite nuclear density region is speculated to be the cause.

Measurement of flux from deuterium, where the nuclear density effect is minimal, will be an important baseline to establish for clarifying the role.

Normalization problem for events of ntag=1?

Normalization factor obtained by Kohri-san using LH2 data

Normalization factor obtained by Sumihama-san using LD2 data

Not ntag=1 but itagc.f>0 for the use of Sumihama-san’s normalization

ntag=1Normalization factor obtained by Kohri-san using LH2 data

itagc.f>0Normalization factor obtained by Sumihama-san using LD2 data

DK+K X

Differential Cross Sections ofNN incoherent interaction

Differential Cross Sections ofNN at t=tmin

Decay asymmetry of NN at |t-tmin|<0.1 GeV2

Mass Number Dependence of Nuclear Transparency ratio

P dependence?KK; mixing

Strong suppression is seen in D target. Nuclear density effect is unlikely to be the main cause for the suppression.

D. Cabrera et al. / Nuclear Physics A 733 (2004) 130–141

P dependence is weak in the regionOf 1000-2000 MeV.