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Status of the Soudan 2 nucleon decay experiment

Description: Soudan 2 is an 1100-ton fine-grained tracking calorimeter now being constructed to search for nucleon decay. It is distinguished by superior background rejection for a wide variety of decay modes and by a trigger threshold low enough for 100 MeV neutrino-induced muons. A new laboratory large enough for an eventual 3300 ton experiment has been constructed in Minnesota's Soudan mine at a depth equivalent to 2200 meters of water. The detector will be assembled from 256 5-ton calorimeter modules, utilizing corrugated steel sheets and plastic drift tubes to obtain a rather isotropic honeycomb geometry. Data collection will begin in the fall of 1986 and assembly of the 1100 tons will be completed in 1988. Installation progress and the performance of the first 5-ton modules will be described. 3 refs., 1 fig.
Date: June 1, 1986
Creator: May, E.N.
Partner: UNT Libraries Government Documents Department

Portable parallel programming in a Fortran environment

Description: Experience using the Argonne-developed PARMACs macro package to implement a portable parallel programming environment is described. Fortran programs with intrinsic parallelism of coarse and medium granularity are easily converted to parallel programs which are portable among a number of commercially available parallel processors in the class of shared-memory bus-based and local-memory network based MIMD processors. The parallelism is implemented using standard UNIX (tm) tools and a small number of easily understood synchronization concepts (monitors and message-passing techniques) to construct and coordinate multiple cooperating processes on one or many processors. Benchmark results are presented for parallel computers such as the Alliant FX/8, the Encore MultiMax, the Sequent Balance, the Intel iPSC/2 Hypercube and a network of Sun 3 workstations. These parallel machines are typical MIMD types with from 8 to 30 processors, each rated at from 1 to 10 MIPS processing power. The demonstration code used for this work is a Monte Carlo simulation of the response to photons of a ''nearly realistic'' lead, iron and plastic electromagnetic and hadronic calorimeter, using the EGS4 code system. 6 refs., 2 figs., 2 tabs.
Date: January 1, 1989
Creator: May, E.N.
Partner: UNT Libraries Government Documents Department

On persistence interfaces for scientific data stores

Description: A common dilemma among builders of large scientific data stores is whether to use a lightweight object persistence manager or a genuine object-oriented database. There are often good reasons to consider each of these strategies; a few are described in this paper. Too often, however, electing to use a lightweight approach has meant programming to an interface that is entirely different than that expected by commercial object-oriented databases. With the emergence of object database standards, it is possible to provide an interface to persistence managers that does not needlessly inhibit coexistence with (and, perhaps, eventual migration to) object-oriented databases. This paper describes an implementation of a substantial subset of the ODMG-93[1]C++ specification that allows clients to use many of today`s lightweight object persistence managers through an interface that conforms to the ODMG standard. We also describe a minimal interface that persistence software should support in order to provide persistence services for ODMG implementations.
Date: February 9, 1996
Creator: Malon, D.M. & May, E.N.
Partner: UNT Libraries Government Documents Department

Data preprocessor and compactor for the Soudan 2 nucleon decay experiment

Description: This paper describes a prototype preprocessor data-compaction system for the Soudan 2 proton decay search experiment. The Soudan 2 experiment will have more than three million potential data words per event to examine, while less than one percent of these data words will have valid data for typical events. In an effort to reduce the amount of data to be stored and analyzed, a data preprocessor was developed which scans the data words. If a data word is valid (ADC count above a preset threshold), that data word is passed to the host computer for experiment monitoring and storage on magnetic tape. To obtain fast data compression, a hardware comparator is used. The hardware comparator places valid data into a FIFO (first in first out stack) where the host computer can acquire the data through CAMAC. The comparator and FIFO are controlled by a microprocessor (8086 CPU), and the microprocessor is programmed for decision-making and communication between the compactor, CAMAC, the host computer and a local terminal.
Date: January 1, 1984
Creator: Dawson, J.W.; May, E.N. & Solomey, N.
Partner: UNT Libraries Government Documents Department

Flexible storage services for parallel data mining

Description: The demands of mining and analyzing vast amounts of data often lead scientists to supercomputer centers, with their high-performance parallel processors and large-scale hierarchical storage. Once there, however, clients quickly come face to face with a number of harsh realities. Common constraints are: (1) disk space, while impressive in aggregate on machines with more than 100 nodes, generally amounts to only a couple of gigabytes per node; (2) local disk space is scratch space every query starts and ends with no data on compute nodes` local disks; (3) mass storage is generally a (widely) shared resource, and is not user- configurable; (4) machine use is scheduled- no daemon processes may be left running; (5) while some nodes may be ``closer`` than others (e.g., HIPPI-connected) to mass storage, current schedulers tend nonetheless to allow users to specify only the number of nodes desired, not their I/O topology; (6) mass storage access from multiple nodes may in fact be routed through a single node (e.g., a distinguished I/O node per rack).
Date: December 31, 1996
Creator: Malon, D.M. & May, E.N.
Partner: UNT Libraries Government Documents Department

Critical database technologies for high energy physics

Description: A number of large-scale high energy physics experiments loom on the horizon, several of which will generate many petabytes of scientific data annually. A variety of exploratory projects are underway within the physics computing community to investigate approaches to managing the data. There are conflicting views of this massive data problem: (1) there is far too much data to manage effectively within a genuine database; (2) there is far too much data to manage effectively without a genuine database; and many people hold both views. The purpose of this paper is to begin a dialog between the computational physics and very large database community on such problems, and to simulate research in directions that will be of benefit to both groups. This paper will attempt to outline the nature and scope of these massive data problems, survey several of the approaches being explored by the physics community, and suggest areas in which high energy physicists hope to look to the database community for assistance.
Date: September 1, 1997
Creator: Malon, D.M. & May, E.N.
Partner: UNT Libraries Government Documents Department

An ODMG-compatible testbed architecture for scalable management and analysis of physics data

Description: This paper describes a testbed architecture for the investigation and development of scalable approaches to the management and analysis of massive amounts of high energy physics data. The architecture has two components: an interface layer that is compliant with a substantial subset of the ODMG-93 Version 1.2 specification, and a lightweight object persistence manager that provides flexible storage and retrieval services on a variety of single- and multi-level storage architectures, and on a range of parallel and distributed computing platforms.
Date: February 17, 1997
Creator: Malon, D.M. & May, E.N.
Partner: UNT Libraries Government Documents Department

Object database standards, persistence specifications, and physics data

Description: Designers of data systems for next-generation physics experiments face a bewildering array of potential paths. On the one hand, object data base technology is quite promising, and standardization efforts are underway in this arena. On another, lightweight object managers may offer greater potential for delivering the high performance needed from petabyte-scale data stores, and may allow more efficient tailoring to specific parallel and distributed environments, as well as to multilevel storage. Adding to the confusion is the evolution of persistence services specifications such as those promulgated by the Object Management Group (OMG). In this paper, we describe what we have learned in efforts to implement a physics data store using several of these technologies, including a lightweight object persistence manager aiming at plug-and-play with object databases, and a trial implementation of the OMG Persistent Data Services Direct Access protocol.
Date: December 31, 1995
Creator: Malon, D.M.; May, E.N.; Grossman, R.L.; Day, C.T. & Quarrie, D.R.
Partner: UNT Libraries Government Documents Department

Data analysis in an Object Request Broker environment

Description: Computing for the Next Millenium will require software interoperability in heterogeneous, increasingly object-oriented environments. The Common Object Request Broker Architecture (CORBA) is a software industry effort, under the aegis of the Object Management Group (OMG), to standardize mechanisms for software interaction among disparate applications written in a variety of languages and running on a variety of distributed platforms. In this paper, we describe some of the design and performance implications for software that must function in such a brokered environment in a standards-compliant way. We illustrate these implications with a physics data analysis example as a case study.
Date: December 31, 1995
Creator: Malon, D.M.; May, E.N.; Grossman, R.L.; Day, C.T. & Quarrie, D.R.
Partner: UNT Libraries Government Documents Department

Properties of the. omega. p resonance at 1. 8 GeV observed in p polarized p. -->. p. omega. p at 11. 75 GeV/c

Description: Preliminary results from a sample of approx. 20,000 events of the reaction pp..-->..p..omega..p obtained using the ZGS 11.75-GeV/c polarized proton beam and the Effective Mass Spectrometer are presented. An enhancement in the ..omega..p mass distribution with mass 1.810 +- 0.025 GeV and width 0.140 +- 0.040 GeV is observed. The t distribution of this enhancement shows a pronounced dip near -t = 0.2 GeV/sup 2/; this dip suggests that the production mechanism is mostly ..omega..-exchange. The decay angular distributions are consistent with a spin-parity of 2/sup 3 -/. 4 figures.
Date: January 1, 1980
Creator: Arenton, M.W.; Ayres, D.S.; Diebold, R.; May, E.N.; Nodulman, L.; Sauer, J.R. et al.
Partner: UNT Libraries Government Documents Department

Construction and operation of a drift-collection calorimeter

Description: Large areas planar drift chambers with long drift distance (up to 50 cm) have been developed for possible use in the new Soudan 2 nucleon decay detector. Design goals included fine sampling to determine the topology of complex events with several low-energy tracks. The large scale of the experiment (> 1000 metric tons) required large area inexpensive chambers, which also had good position resolution and multi-track separation. The chambers were to be installed between thin sheets of steel to form a finegrained detector. A second goal was the sampling of dE/dx with each position measurement, in order to determine the direction and particle identity of each track. In this paper we report on the construction and operation of a prototype dectector consisting of 50 chambers, separated by 3 mm-thick steel plates. Readout of drift time and pulse height from anode wires and an orthogonal grid of bussed cathode pads utilized 6-bit flash ADC's. This application of the drift-collection calorimeter technique to a nucleon decay detector follows the investigation by a number of groups of calorimeters for high energy detectors based on long drifting.
Date: January 1, 1984
Creator: Ambats, I.; Ayres, D.S.; Dawson, J.W.; Hoftiezer, J.H.; Mann, W.A.; May, E.N. et al.
Partner: UNT Libraries Government Documents Department

Construction of the Soudan 2 detector

Description: The authors reported here on the progress in construction of the Soudan 2 nucleon decay detector which is being built at the Soudan iron mine in Minnesota. The authors also report the expected event rate and characteristics of low energy neutrino events, muon events, multiple muon events, and other cosmic ray phenomena which the authors might be sensitive to.
Date: January 1, 1985
Creator: Ayres, D.S.; Barrett, W.L.; Dawson, J.W.; Fields, T.H.; Goodman, M.C.; Hoftiezer, J. et al.
Partner: UNT Libraries Government Documents Department

High Energy Physics Division semiannual report of research activities, January 1, 1999--June 30, 1999.

Description: In the period January--June 1999 accomplishments for the ANL-HEP division medium energy physics project consisted of the completion of two papers on past Saclay experiments, the beginning of analysis of recent data from the Crystal Ball measurements at the Brookhaven AGS, and preparations for a RHIC polarimeter. Two papers on Saclay pp elastic scattering data were completed by an ANL physicist, submitted and accepted in Physical Review. Results for the spin observable P - A{sub oono} = A{sub ooon} = A{sub y} at over 30 beam kinetic energies between 800 and 2,800 MeV and C.M. angles from about 70{degree}--110{degree} are described. A total of 919 new data points are presented in these articles. The energy dependence at fixed c.m. angles appears smooth, with no evidence for rapid energy-dependent structure. Work has also begun on two additional papers at Argonne and on others at Saclay.
Date: January 26, 2000
Creator: Spinka, H.; Nodulman, L.; Goodman, M.C.; Repond, J.; Proudfoot, J.; Underwood, D. et al.
Partner: UNT Libraries Government Documents Department

High Energy Physics division semiannual report of research activities, January 1, 1998--June 30, 1998.

Description: This report describes the research conducted in the High Energy Physics Division of Argonne National Laboratory during the period of January 1, 1998 through June 30, 1998. Topics covered here include experimental and theoretical particle physics, advanced accelerator physics, detector development, and experimental facilities research. Lists of Division publications and colloquia are included.
Date: March 9, 1999
Creator: Ayres, D. S.; Berger, E. L.; Blair, R.; Bodwin, G. T.; Drake, G.; Goodman, M. C. et al.
Partner: UNT Libraries Government Documents Department

Underground muons from the direction of Cygnus X-3

Description: We report on 3.2 years live time of underground muon observations taken between 1981 and 1989 using the Soudan 1 proportional tube detector, located at a depth of 1800 m water equivalent. The post-1984 observations are consistent with our earlier data on an excess signal apparently correlated with the Cygnus X-3 orbital period. The signal-to-background ratio in the entire data sample is 1 to 3 percent, depending on phase width. 10 refs., 2 figs., 1 tab.
Date: September 11, 1989
Creator: Johns, K.; Marshak, M.L.; Peterson, E.A.; Ruddick, K.; Shupe, M. (Minnesota Univ., Minneapolis, MN (USA). School of Physics and Astronomy); Ayres, D.S. et al.
Partner: UNT Libraries Government Documents Department

Contained [nu] events observed in Soudan 2

Description: Atmospheric [nu][sub [mu]] and [nu][sub e] are created in cosmic ray interactions in the atmosphere, and can be detected in underground detectors. The Kamiokande and IMB water Cerenkov detectors have found fewer [nu][sub [mu]] interactions (relative to [nu][sub e]) than are expected. Results are usually expressed by the ratio: R[triple bond]([nu][sub [mu]]/[nu][sub [mu]]) measured ([nu][sub [mu]]/[nu][sub e]) predicted with R found to be less than 1. The Soudan 2 detector is an iron calorimeter, which has different systematic effects than the water Cerenkov counters. Results from the Frejus and NUSEX calorimeters do not suggest a deficit of [nu][sub [mu]]'s in iron, implying that perhaps there is a systematic effect in Cerenkov detectors or some unexpected nuclear effect. Here we report on a preliminary analysis of 0.5 kton-year of data in Soudan 2. We are presently analyzing our second 0.5 kt-year of data, and will present new results at the meeting.
Date: January 1, 1993
Creator: Ambats, I.; Ayres, D.S.; Balka, L.; Barrett, W.L.; Dawson, J.; Fields, T. et al.
Partner: UNT Libraries Government Documents Department

Multiple muon events in Soudan 2

Description: This is a progress report on multiple muon events recorded by the Soudan 2 detector. 6 refs.
Date: August 1, 1991
Creator: Allison, W. W. M.; Barr, G. D.; Brooks, C. B.; Cobb, J. H.; Kirby-Gallagher, L. M.; Giles, R. H. et al.
Partner: UNT Libraries Government Documents Department

Muon/electron separation for atmospheric neutrino interactions

Description: A study has been made of the ability of the Soudan 2 nucleon decay detector to distinguish between showering and non-showering particles, utilizing several different pattern recognition techniques. This work has direct application in the determination of the {nu}{sub {mu}}/{nu}{sub e} ratio for atmospheric neutrino induced events. The results of the application of these techniques to Monte Carlo data and to calibration data from the ISIS test beam are presented.
Date: August 1, 1991
Creator: Allison, W. W. M.; Barr, G. D.; Brooks, C. B.; Cobb, J. H.; Kirby-Gallagher, L. M.; Giles, R. H. et al.
Partner: UNT Libraries Government Documents Department

Simultaneous observations of extensive air showers and underground muons at Soudan 2

Description: We have built a small proportional tube air shower array on the surface above the Soudan 2 proton decay detector in Soudan, Minnesota, USA. This array, in coincidence with the underground detector, allows simultaneous surface and underground observations of high energy cosmic ray showers. These observations, still in their initial stages, may eventually be able to provide information about the composition of cosmic ray primaries in the ``knee`` region of the energy spectrum. 4 refs.
Date: August 1, 1991
Creator: Allison, W. W. M.; Barr, G. D.; Brooks, C. B.; Cobb, J. H.; Giles, R. H.; Perkins, D. H. et al.
Partner: UNT Libraries Government Documents Department

Underground muons observed in the Soudan 2 detector from the directions of x-ray sources

Description: We report on observations of underground muons made with the Soudan 2 proton decay detector at a depth of 2090 mwe from the directions of the binaries Hercules X-1 and 1E2259+586 and the Crab pulsar.
Date: August 1, 1991
Creator: Allison, W. W. M.; Barr, G. D.; Brooks, C. B.; Cobb, J. H.; Giles, R. H.; Perkins, D. H. et al.
Partner: UNT Libraries Government Documents Department

A search for magnetic monopoles with the Soudan 2 detector

Description: A search for GUT magnetic monopoles has been conducted using the Soudan 2 nucleon decay detector. This detector is a fine-grained tracking calorimeter. Monopole candidates were selected on the basis of significantly higher ionization than throughgoing cosmic ray muons. Preliminary results, using data taken over approximately one year with no monopoles observed, correspond to a flux limit of 2.4 10{sup {minus}14}cm{sup {minus}2}sr{sup {minus}1}s{sup {minus}1} over a velocity range of 10{sup {minus}3} < {beta} < 0.95. 8 refs.
Date: August 1, 1991
Creator: Allison, W. W. M.; Barr, G. D.; Brooks, C. B.; Cobb, J. H.; Kirby-Gallagher, L. M.; Giles, R. H. et al.
Partner: UNT Libraries Government Documents Department