Status Report of Neutral Kaon photo-production study using Neutral Kaon Spectrometer 2 (NKS2) at LNS-Tohoku(I. Nuclear Physics)

The approach described in this paper uses an array of Field Programmable Gate Array (FPGA) devices to implement a fault tolerant hardware system that can be compared to the running of fault tolerant software on a traditional processor. Fault tolerance is achieved is achieved by using FPGA with on the fly partial programmability feature. Major considerations while mapping to the FPGA includes the size of the area to be mapped and communication issues related to their communication. Area size selection is compared to the page size selection in Operating System Design. Communication issues between modules are compared to the software engineering paradigms dealing with module coupling, fan-in, fan-out and cohesiveness. Finally, the overhead associated with the downloading of the reconfiguration files is discussed

Installation of a Dipole Electromagnet RTAGX(I. Nuclear Physics)

A dipole electromagnet RTAGX has been installed in the GeV-γ experimental hall. It sweeps out charged particles contaminated in the incident γ beam for meson photo-production experiments. It also supplies momentum-analyzed electrons or positrons in a newly constructed test beamline

Construction of a Forward Electro-magnetic Calorimeter SCISSORS III(I. Nuclear Physics)

A new electro-magnetic calorimeter complex FOREST with a solid angle of about 4π in total is under construction. It consists of three calorimeters: a forward one with CsI crystals, a middle one with lead scintillating fiber modules, and a backward one with lead glass Cerenkov counters. Recently, the forward calorimeter SCISSORS III takes shape

Photoproduction of η-mesons off C and Cu Nuclei for Photon Energies below 1.1 GeV(I. Nuclear Physics)

The η-meson photoproduction cross sections have been measured on C and Cu targets for photon energies between 600 and 1100MeV to investigate the behavior of the S_11 (1535) resonance in a nucleus. The excitation functions of the cross section as well as angular and momentum distributions of η-mesons are in quantitative agreement with Quantum Molecular Dynamics (QMD) model calculations, in which the η-meson emission processes other than the S_11 (1535) resonance are also incorporated as proposed in the η-MAID model. It is shown that the excitation of the D_15 (1675) resonance might play an important role for E_γ>900MeV

Non-strange dibaryons studied in coherent double neutral-meson photoproduction on the deuteron

The B = 2 bound/resonance state (dibaryon) is an interesting object, which can be a molecule consisting of two baryons or a spatially compact hexaquark hadron object. The yd ^ n°n°d reaction has been experimentally investigated at incident energies ranging from 0.58 to 1.15 GeV to study non-strange dibaryons. The angular distributions of deuteron emission in the yd center-of-mass energy cannot be reproduced by quasi-free production of two neutral pions followed by deuteron coalescence. Additionally a 2.14-GeV peak is observed in the n°d invariant mass distribution. These suggest a sequential process such as yd ^ RIS ^ n°RIV ^ n°n°d with an isoscalar dibaryon RIS and an isovector dibaryon RIV. Since the mass of the observed isoscalar dibaryons are close to the sum of the nucleon (N) and nucleon resonance (N*) masses, an S-wave NN* molecule may play a role as a doorway to a dibaryon