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

Double Pion Photoproduction on Deuteron(I. Nuclear Physics)

Exclusive cross sections for double-pion photoproductions on proton and deuteron were measured in an energy range from 0.8 to 1.1GeV using tagged photons at Laboratory of Nuclear Science, Tohoku University. We employed the Neutral Kaon Spectrometer (NKS) to detect two pions in the final state, and deduced the cross section for the π^+π^- photoproduction on the "free" and "bound" proton. We have discriminated between the quasi-free and non-quasi-free process applying the kinematical cut on the missing momentum. We found that the total cross section for the γ"p"→pπ^+π^- reaction was about 60% of that for the "free" proton, and this is consistent with the previously obtained data. The one of the dominant part of the non-quasi-free process was found to be the double Δ production. Its cross section is smaller than the previous investigations