Brookhaven Segment Interconnect

We have performed a high energy physics experiment using a multisegment Brookhaven FASTBUS system. The system was composed of three crate segments and two cable segments. We discuss the segment interconnect module which permits communication between the various segments

Brookhaven Fastbus/Unibus Interface

A typical high energy physics experiment requires both a high speed data acquisition and processing system, for data collection and reduction; and a general purpose computer to handle further reduction, bookkeeping and mass storage. Broad differences in architecture, format or technology, will often exist between these two systems, and interface design can become a formidable task. The PDP-11 series minicomputer is widely used in physics research, and the Brookhaven FASTBUS is the only standard high speed data acquisition system which is fully implemented in a current high energy physics experiment. This paper will describe the design and operation of an interface between these two systems. The major issues are elucidated by a preliminary discussion on the basic principles of Bus Systems, and their application to Brookhaven FASTBUS and UNIBUS

Mini- and micro-processors and FASTBUS in the experimental program at BNL. [FASTBUS]

The use of small processors in the experimental program at Brookhaven is reviewed. FASTBUS, a new data acquisition system, as developed at BNL is also reviewed. New directions that are planned in these areas are discussed

FASTBUS system used in a high energy experiment

Experiment No. 735, now being executed at the A.G.S. is implemented in FASTBUS. Briefly, this data acquisition system is designed to operate and gather data from high energy physics experiments at sub-microsecond speeds. It is a 32 bit bus system capable of operating at near-gigabit rates. The bus can be segmented with each segment operating independently when not communicating with each other. The system is based upon a very fast integrated circuit family, emitter coupled logic or ECL

Quark search at the CBA

An experiment to search for quarks at the CBA is described. The cross sections for the production of massive quark-antiquark pairs in nucleon-nucleon interactions is estimated, and the experimental design and procedures are described. (WHK

Measurement of epsilon'/epsilon

After twenty years of intense scrutiny CP violation is apparently still well described, if not explained, by the superweak hypothesis, in which absolute values ..delta..S = 2 (T-violating) transitions between the K/sup 0/, anti K/sup 0/ states induce CP violating impurities in the K/sub L//sup 0/, K/sub S//sup 0/ states. CP-violating effects observed in the K/sup 0/ - anti K/sup 0/ system can be described in terms of one parameter, absolute values epsilon approx. = 2 x 10/sup -3/, which defines the portion of the CP-even state K/sub 1//sup 0/ found in the predominantly CP-odd K/sub L//sup 0/ state: K/sub L//sup 0/ proportional to K/sub 2//sup 0/ + epsilon K/sub 1//sup 0/. A precise measurement of the relative rates for the CP-violating decays K/sub L//sup 0/ ..-->.. ..pi../sup +/..pi../sup -/ and K/sub S//sup 0/ ..-->.. ..pi../sup 0/..pi../sup 0/ in principle provides a test for absolute values ..delta..S = 1 CP-violating amplitudes which result in deviations from the superweak predictions: eta /sup 00/ = eta /sup + -/ = epsilon, where eta /sup + -/ and eta /sup 00/ are the ratios of K/sub L/ to K/sub S/ decay amplitudes into ..pi../sup +/..pi../sup -/ and ..pi../sup 0/..pi../sup 0/ final states. Gauge theory models of CP-violation are in general constructed to nearly mimic superweak predictions by having the dominant contribution to CP-violation arise from complex terms in the K/sup 0/ - anti K/sup 0/ mixing amplitudes. However, there are usually additional contributions in the form of direct CP violating absolute values ..delta..S = 1 decay amplitudes, parametrized by epsilon', which are not identical for the weak transitions into isospin I = 0 and 2 ..pi pi.. final states. The Yale-BNL group has recently completed a measurement of R and thus epsilon'/epsilon at the Brookhaven AGS. Results are presented

Search for flavor changing neutral currents K/sub L/ /sup +-/e/sup /minus plus//, e e and e e

We report on a search for the flavor-changing neutral-current decays K/sub L/ e e , K/sub L/ e e and K/sub L/ /sup +-/e/sup /minus plus//. Limits obtained for these processes are BR(K/sub L/ e e ) < 3.2 x 10 X, BR(K/sub L/ e e ) < 1.2 x 10 Z, BR(K/sub L/ /sup +-/e/sup /minus plus//) < 1.9 x 10 Z. 10 refs., 8 figs

A search for effective flavour changing neutral currents in K/sub L//sup 0/ decays

A dedicated search for the decays K/sub L//sup 0/ /yields/ /mu/e, K/sub L//sup 0/ /yields/ ee and K/sub L//sup 0/ /yields/ /mu//mu/, was carried out at the Brookhaven National Laboratory AGS (E780). The data obtained were also used in a search for the three-body decays K/sub L//sup 0/ /yields/ /pi//sup 0/l /sup /plus/1/sup /minus//. The two body modes were normalized to the kinelatically similar, CP violating, decay K/sub L//sup 0/ /yields/ /pi//sup (plus///pi//sup /minus//; whereas the three body modes were normalized to the decay K/sub L//sup 0/ /yields/ /pi//sup 0//pi//sup /plus//pi//sup /minus//. The search was performed on a sample of K/sup 0/ mesons produced in the forward direction by the interactions of 29 GeV protons on a copper target, and decaying in a 3 meter long region, starting augmented by a hydrogen Cerenkov counter and a lead glass electromagnetic calorimeter, for electron identification, and by a range stack, for muon identification. 9 refs., 5 figs., 2 tabs

Search for rare decays of the K/sub L//sup 0/

We report on a search for the rare decays K/sub L//sup 0/ ..-->.. ..mu../sup +-/e/sup /minus plus//, K/sub L//sup 0/ ..-->.. e/sup +/e/sup /minus//, and K/sub L//sup 0/ ..-->.. ..pi../sup 0/e/sup +/e/sup /minus// at the Brookhaven AGS. Limits obtained for these processes are BR(K/sub L//sup 0/ ..-->.. ..mu../sup +-/e/sup /minus plus//) .. e/sup +/e/sup /minus//) .. ..pi../sup 0/e/sup +/e/sup /minus//) < 3.2 /times/ 10/sup /minus/7/. 4 refs., 2 figs

Data Processing in AGS Experiment 780

Experiment 780 is a search for the rare K decays K/sub L//sup 0/ ..-->.. ..mu..e and K/sub L//sup 0/ ..-->.. e/sup +/e/sup -/. We will be sensitive to these decays if the branching ratio is above 10/sup -10/. To achieve this in a 1000 hr experiment will require an intense beam with about 2 x 10/sup 5/ K decays/sec in the three meter decay region and over 10/sup 7/ counts/m/sup 2//sec in the apparatus. We will need a multilevel event selection sequence which will accept good events with high efficiency but quickly reject most of the background events. 1 ref