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Jefferson Lab, a status report

Description: Thomas Jefferson National Accelerator Facility (Jefferson Lab; formerly known as CEBAF), operates a 4 GeV, 200 {micro}A continuous wave (CW) electron accelerator that re-circulates the beam five times through two superconducting 400 MeV linacs. Electrons can be extracted from any of the five recirculation passes and beam can be simultaneously delivered to the three experimental halls. As the commissioning stage nears completion, the accelerator is becoming a fully operational machine. Experiments in Hall C have been underway since November 1995 with beam powers of over 300 kW at various energies. Hall A has received beam for spectrometer commissioning, while Hall B is expected to receive its first beam in the fall of 1996. Accelerator availability of greater than 70% during physics runs and excellent beam quality have contributed to making Jefferson Lab a world class laboratory for accelerator-based electromagnetic nuclear physics. With the high performance of the superconducting RF cavities, machine upgrades to 6 GeV, and eventually 8 to 10 GeV are now in the planning stages. Operational and commissioning details concerning all aspects of the machine will be discussed.
Date: October 1, 1996
Creator: Dunham, B. M.
Partner: UNT Libraries Government Documents Department

Space-charge-dominated beam dynamics simulations using the massively parallel processors (MPPs) of the Cray T3D

Description: Computer simulations using the multi-particle code PARMELA with a three-dimensional point-by-point space charge algorithm have turned out to be very helpful in supporting injector commissioning and operations at Thomas Jefferson National Accelerator Facility (Jefferson Lab, formerly called CEBAF). However, this algorithm, which defines a typical N{sup 2} problem in CPU time scaling, is very time-consuming when N, the number of macro-particles, is large. Therefore, it is attractive to use massively parallel processors (MPPs) to speed up the simulations. Motivated by this, the authors modified the space charge subroutine for using the MPPs of the Cray T3D. The techniques used to parallelize and optimize the code on the T3D are discussed in this paper. The performance of the code on the T3D is examined in comparison with a Parallel Vector Processing supercomputer of the Cray C90 and an HP 735/15 high-end workstation.
Date: October 1, 1996
Creator: Liu, H.
Partner: UNT Libraries Government Documents Department

Correction of dispersion and the betatron functions in the CEBAF accelerator

Description: During the commissioning of the CEBAF accelerator, correction of dispersion and momentum compaction, and, to a lesser extent, transverse transfer matrices were essential for robust operation. With changing machine conditions, repeated correction was found necessary. To speed the diagnostic process the authors developed a method which allows one to rapidly track the machine optics. The method is based on measuring the propagation of 30 Hz modulated betatron oscillations downstream of a point of perturbation. Compared to the usual methods of dispersion or difference orbit measurement, synchronous detection of the beam displacement, as measured by beam position monitors, offers significantly improved speed and accuracy of the measurements. The beam optics of the accelerator was altered to decrease lattice sensitivity at critical points and to simplify control of the betatron function match. The calculation of the Courant-Snyder invariant from signals of each pair of nearby beam position monitors has allowed one to perform on-line measurement and correction of the lattice properties.
Date: October 1, 1996
Creator: Lebedev, V. A.; Bickley, M.; Schaffner, S.; Zeijts, J. van; Krafft, G. A. & Watson, C.
Partner: UNT Libraries Government Documents Department

Measurement of the angular distribution of the electron from W {r_arrow} e = {nu} decay, in p{anti p} at {radical}s = 1.8 TeV, as function of P{sub T}{sup W}; Medida de la distribucion angular del electron de W en e + neutrino en p{anti p} a 1.8 TeV

Description: The goal of this work was to study the behavior of the angular distribution of the electron form the decay of the W boson in a specific rest-frame of the W, the Collins-Soper frame. This thesis consists of four major divisions, each dealing with closely related themes: (a) Physics Background, (b) Description of the Hardware and General Software Tools, (c) Description of the Analysis and Specific Tools, and (d) Results and Conclusions. Each division is comprised of one or more chapters and each chapter is divided into sections and subsections.
Date: October 7, 1996
Creator: Ramos, M. I. M.
Partner: UNT Libraries Government Documents Department

An Assessment Strategy: Fun & Games

Description: A newsletter clipping featuring an article on a computer game titled "ART-GO," a reworking design of Bingo. Art-Go was designed to encourage a synthesis of ideas in the form of art thinking and art talking, a solution to the artist assessment problem - to measure the art cognition. The object of Art-Go, to develop observational skills and expressive dialogue that demonstrates what art concepts students understand or mis-understand.
Date: October 1996
Creator: School Arts
Partner: UNT Libraries Special Collections

[The Role of Art in Higher Level Thinking]

Description: A newspaper clipping featuring an article on the upcoming FORTE meeting, October 9th where guest speaker Dr. William McCarter will be discussing "The Role of Art in Higher Level Thinking." FROTE is an alliance of parents, teachers, students, administrators and board trustees dedicated to enhancing education for gifted and high achieving students.
Date: October 6, 1996
Creator: Grapevine Sun
Partner: UNT Libraries Special Collections

[RE: Goals 2000 Arts Education Partnership Meeting Notes]

Description: Photocopy of a memo from Julie Abel, program associate of the Getty Center for Education in the Arts, to the Regional Institute Grant Directors. The memo is in regards to the key points and recommendations from the September 20, 1996 Goals 2000 Arts Educational Leadership fund meeting. Attached with the memo is the meeting report.
Date: October 14, 1996
Creator: Abel, Julie
Partner: UNT Libraries Special Collections

[News Clip: Kissing kid]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 10pm.
Date: October 2, 1996, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Tower impact]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 6pm.
Date: October 12, 1996, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Trench rescue]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 5pm.
Date: October 2, 1996, 5:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Vacaville fire]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 12pm.
Date: October 11, 1996, 12:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Routier]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 10pm.
Date: October 19, 1996, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Routier]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 10pm.
Date: October 10, 1996, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Routier]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 6pm.
Date: October 18, 1996, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Routier house]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 10pm.
Date: October 17, 1996, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Routier]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 10pm.
Date: October 10, 1996, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Sculpture]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 5pm.
Date: October 28, 1996, 5:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Service biz]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 10pm.
Date: October 30, 1996, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Skunk]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 5pm.
Date: October 21, 1996, 5:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Soccer mom]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 6pm.
Date: October 22, 1996, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Mom - murder]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. Story aired at 10pm.
Date: October 14, 1996, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections