Y. Nagasaka

PHENIX central arm particle ID detectors

Abstract The Ring-Imaging Cherenkov (RICH) and the Time-of-Flight (ToF) systems provide identification of charged particles for the PHENIX central arm. The RICH is located between the inner and outer tracking units and is one of the primary devices for identifying electrons among the very large number of charged pions. The ToF is used to identify hadrons and is located between the most outer pad chamber (PC3) and the electromagnetic calorimeter. A Time Zero (T0) counter that enhances charged particle measurements in p–p collisions is described. Details of the construction and performance of both the RICH, ToF and T0 are given along with typical results from the first PHENIX data taking run.

Ring imaging Cherenkov detector of PHENIX experiment at RHIC

Abstract The RICH detector of the PHENIX experiment at RHIC is currently under construction. Its main function is to identity electron tracks in a very high particle density, about 1000 charged particles per unit rapidity, expected in the most violent collisions at RHIC. The design and construction status of the detector and its expected performance are described.

Time-slot interchanger for self-routing event building

Abstract An event builder based on a sorting network has been developed. The key components of the event builder are a comparator used as a node of the network, and a time slot interchanger (TSI), which arranges input data fragments. Since the data fragments determine their path in the network, no complicated software control is needed for the event builder. The sorting network has scalability for the size of the readout system, because of its recursive characteristics and capability of downsizing. In order to deduce these features, a time slot interchanger (TSI) was newly developed. The throughput of the data and scalability were examined for various speeds of the system clocks and the number of input channels. The TSI has sufficient scalability of the speed and the network-size.

The PHENIX ring imaging Cherenkov detector

Abstract The PHENIX experiment at RHIC is primarily a lepton and photon detector. Electron detection takes place in the two central arms of PHENIX, with the primary electron identifier in each arm being a ring imaging Cherenkov detector. This paper contains a description of the two identical RICH detectors and of their expected performance.

Data-acquisition system for a target multifragmentation experiment with large solid angle detectors

Abstract We have developed a CAMAC data-acquisition system that is capable of handling not only high-rate interruptions, but also over one hundred inputs within a single CAMAC crate in order to perform exclusive measurements of target multifragmentation induced by 8 and 12xa0GeV primary proton beams on heavy nuclei. The system is run under PC-Linux and a CAMAC auxiliary crate controller. Since we have selected the UNIDAQ data-acquisition system for our DAQ software, which only uses standard UNIX technology, we expect easy migration to another platform in a future system upgrade.

SELF-ROUTING EVENT BUILDING ON SORTING NETWORK

Abstract Event building system based on sorting network has been developed and discussed. The event builder comprises a comparator with subsidiary functions as a network node, FIFOs as a time slot interchanger at the input stage and data buffers at the output stage. The event building system gathers data without any complex controls by the software. The throughput of the data and scalability were examined for various speeds of the system clocks. The system has a scalability of the speed for the network-size. Though the throughput is limited by the speed of the device we chose, the speed can be increased by choosing a faster device.