Showing papers by "Masaharu Nomachi published in 1998"
TL;DR: In this paper, an enormous enhancement of antiproton production in deuteron-and α-induced reactions has been observed in the subthreshold energy region between 2 and 5 GeV/nucleon.
20 citations
01 Dec 1998
TL;DR: In this article, the authors present the design and preliminary performance of the processing electronic system of the Hard x-ray Detector (HXD) on the fifth Japanese xray astronomy satellite, Astro-E, scheduled for launch in 2000.
Abstract: The Hard x-ray Detector (HXD) is one of three instruments on the fifth Japanese x-ray astronomy satellite, Astro-E, scheduled for launch in 2000. The sensitivity of the Astro-E HXD will be higher by more than one order of magnitude than that of nay previous instrument between 10 keV and several 100 keV. The electronic system is designed to handle many independent data channels from the HXD within the limitation of size and power consumption required in Astro-E. In this paper, we will present the design and the preliminary performance of the processing electronic system.
17 citations
13 citations
10 Nov 1998
TL;DR: In this article, the first results of the ground test of the hard X-ray detector on board the Astro-E mission were reported by means of the newly developed Ground Support Equipment (GSE).
Abstract: We report the first results of the ground test of the Hard X-ray Detector (HXD) on board the Astro-E mission, by means of the newly developed Ground Support Equipment (GSE). Astro-E will be launched in 2000 by a Japanese M-V rocket. In order to verify the detector system during the limited time before launch, fast and versatile GSE is necessary. For this, we have developed a flexible test system based on nine VME I/O boards for a SUN workstation. These boards carry reconfigurable Field Programmable Gate Arrays with 50,000 gates, together with 1 Mbyte SRAM devices tightly coupled to each FPGA device. As an application of using this GSE, we have tested the performance of a phoswitch unit of the Flight Model of the HXD. In this paper, we present a schematic view of the GSE highlighting the functional design,and the result of our ground test of the HXD-sensor under the high count rate environment expected in orbit.
10 citations
TL;DR: This work has studied the minimal switch configuration for the event builder system in a BELLE experiment in KEK and found that if the switch is not square, a simple barrel shifter is not adequate.
Abstract: It has been stated that an unbalanced data flow cannot be handled by blocking switches such as a barrel shifter. It is not true for a square switch, which has the same number of destination nodes as source nodes. However, if the switch is not square, a simple barrel shifter is not adequate. We have studied the minimal switch configuration for the event builder system in a BELLE experiment in KEK. The performance in the actual experiment was measured.
2 citations
TL;DR: In this article, two arm spectrograph and a liquid-hydrogen target system with well tuned beam provided good event identification at 400 MeV proton energy, at the expense of high computational complexity.
1 citations
TL;DR: The high speed network is a key component in networked data acquisition systems and an ATM switch is a candidate for the network system in a DAQ (data acquisition system) system.
Abstract: The high speed network is a key component in networked data acquisition systems. An ATM switch is a candidate for the network system in a DAQ (data acquisition system). We have studied the DAQ performance of the ATM network at the RCNP (Research Center for Nuclear Physics) at Osaka University. Data traffic on DAQ system has a very different traffic pattern from other network traffic. It may slow down the network performance. We have studied the network performance for several traffic patterns.
1 citations
TL;DR: It is shown that nonblocking circuit switches can handle any requested data flow if the switch-controller is intelligent enough and it is also shown that most event builders do not need nonblocking switches to get high performance.
Abstract: Switch topologies are discussed in terms of graph theory. It is shown that nonblocking circuit switches can handle any requested data flow if the switch-controller is intelligent enough. It is also shown that most event builders do not need nonblocking switches to get high performance.