The LANSCE (Los Alamos Neutron Science Center) runs its LINAC control system based on 30(+) year old technology. While some peripheral upgrades have been made over the years, the control system will need some major improvements over the next five years in order to continue to support the user facility's mission. The proposed multi-million dollar LANSCE-R (Refurbishment) project creates a unique opportunity to upgrade the existing control system. We intend to use the EPICS (Experimental Physics and Industrial Control System) control system with the following goals for effective control at modest cost: (1) Replacing our VMS based MicroVAXes; (2) Replacing the RICE (Remote Instrumentation and Control Equipment) subsystem with Programmable Logic Controllers (PLCs) to handle regular data acquisition and control, and custom hardware to handle "flavored" data acquisition; (3) Replacing the Master Timer subsystem with a modern event system; (4) Converting Fortran programs running on VAX/VMS computers to Java Programs running on Linux-based desktop PCs. The boundary condition, as usual, is that we must implement these major changes on a running accelerator.

The Los Alamos Neutron Science Center (LANSCE) accelerator, an 800-MeV proton linac with a storage ring, has been operated over 30 years since early 1970s. Due to the aging and radiation damage of equipment, cables and connectors, the number of troubles is increasing. In order to reduce the time for unscheduled maintenance, we have implemented a system to catch a symptom of degrading vacuum and send an email automatically. We have been testing this system since July 2006. This paper describes LANSCE vacuum systems, the new alert system and our experience. In addition, we will describe our plan for modernizing the vacuum system in the next few years.

Presently, the Los Alamos National Laboratory is in the process of planning a refurbishment of various subsystems within its Los Alamos Neutron Science Center accelerator facility. A part of this LANSCE facility refurbishment will include some replacement of and improvement to existing older beam-diagnostics instrumentation. While plans are still being discussed, some instrumentation that is under improvement or replacement consideration are beam phase and position measurements within the 805-MHz side-coupled cavity linac, slow wire profile measurements, typically known as wire scanners, and possibly additional installation of fast ionization-chamber loss monitors. This paper will briefly describe the requirements for these beam measurements, what we have done thus far to answer these requirements, and some of the technical issues related to the implementation of the instrumentation.

During the 2005 Los Alamos Neutron Science Center (LANSCE) beam runs, beam current and centroid-fitter data were observed, acquired, analyzed, and documented for both the LANSCE H+ and H- beams. These data were acquired using three beam position monitors (BPMs) from the 100-MeV Isotope Production Facility (IPF) beam line and three BPMs from the Switchyard transport line at the end of the LANSCE 800-MeV linac. The two types of data acquired, intermacropulse and intramacropulse, were analyzed for statistical and frequency characteristics as well as various other correlations including comparing their phase-space like characteristics in a coordinate system of transverse angle versus transverse position. This paper will briefly describe the measurements required to acquire these data, the initial analysis of these jitter data, and some interesting dilemmas these data presented.

The recently completed 100-MeV H+ Isotope Production Facility (IPF) at the LANSCE will provide radioisotopes for medical research and diagnosis, for basic research and for commercial use. A change to the LANSCE accelerator facility allowed for the installation of the IPF. Three components make up the LANSCE accelerator: an injector that accelerates the H+ beam to 750-KeV, a drift-tube linac (DTL) that increases the beam energy to 100-MeV, and a side-coupled cavity linac (SCCL) that accelerates the beam to 800-MeV. The transition region, a space between the DTL and the SCCL, was modified to permit the insertion of a kicker magnet (23 o kick angle) for the purpose of extracting a portion of the 100-MeV H+ beam. A new beam line was installed to transport the extracted H+ beam to the radioisotope production target chamber. This paper will describe the commissioning and initial operating experiences of IPF.

The LANSCE (Los Alamos Neutron Science Center) control system upgrade program continues with the impending replacement of the RICE (Remote Instrumentation and Control Equipment) subsystem. The RICE subsystem upgrade is a challenge because of its technology (late 1960's), number of channels (>10,000), and unique characteristics (all-modules data takes, timed/flavored data takes). The plan is to replace at least the nontimed data and the command portions of the subsystem with Programmable Logic Controllers (PLCs). We discuss motivations, technological challenges, proof-of-principle, and planning. The boundary condition, as usual, is that we must implement these major changes on a running accelerator.

The MEGA experiment, which searched for the muon- and electron-number violating decay μ-> e + γ, is described. The spectrometer system, the calibrations, the data taking procedures, the data analysis, and the sensitivity of the experiment are discussed. The most stringent upper limit on the branching ratio of μ-> e + γ) < 1.2 x 10^{-11} was obtained.

The Los Alamos Neutron Science Center (LANSCE, nee LAMPF) Central Control Room (CCR) has been upgraded. The reasons for the upgrade were to move toward a common operator interface, to increase the control room flexibility for simultaneous beam operations and development, to provide a cleaner and more comfortable control room for 24-hour, eight-month-peryear operations, and to improve the reliability and maintainability of the console interface hardware. The three dedicated-function consoles that serviced two separate control systems were replaced by a single multifunction console divided into three stations. Each station is able to control any part of the facility. The new console contains six three-headed Sun workstations and several mainly-display-oriented X-terminals. Each of the three stations of the new console has a single keyboard. To preserve our investment in VAX-based application programs while the VAX and EPICS control systems are being merged, we have provided X-Windows emulators for old hardware interfaces. A recent paper has described the hardware upgrade[1]. This paper discusses the software aspects of the upgrade.

Historically the Los Alamos Spallation Radiation Effects Facility (LASREF) has used manual methods to control the position of the 800 kW, 800 MeV proton beam on targets. New experiments, however, require more stringent position control more frequently than can be done manually for long periods of time. Data from an existing harp is used to automatically adjust steering magnets to maintain beam position to required tolerances.

Historically the Los Alamos Spallation Radiation Effects Facility (LASREF) has used manual methods to control the position of the 800 kW, 800 MeV proton beam on targets. New experiments, however, require more stringent position control more frequently than can be done manually for long periods of time. Data from an existing harp is used to automatically adjust steering magnets to maintain beam position to required tolerances.

Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation J. J. Szymanski, J. F. Amann, K. Baker, D. Barlow, K. Black, R. D. Bolton, M. Brooks, S. Carius, Y. Chen, M. D. Cooper, P. S. Cooper, J. Crocker, M. Dzemidzic, R. J. Fisk, J. Flick, W. Foreman, C. A. Gagliardi, D. Haim, A. Hallin, R. Harrison, G. Hart, C. M. Hoffman, G. E. Hogan, E. B. Hughes, E. V. Hungerford, K. Johnston, C. Jui, G. J. Kim, J. E. Knott, D. D. Koetke, M. A. Kroupa, T. Kozlowski, K. Lan, D. Lee, F. Liu, R. Manweiler, R. Marshall, B. W. Mayes, R. E. Mischke, F. J. Naivar, B. M. K. Nefkens, J. Novak, M. A. Oothoudt, J. N. Otis, R. Phelps, L. E. Piilonen, C. Pillai, L. Pinsky, J. Price, M. W. Ritter, S. Schilling, T. D. S. Stanislaus, K. M. Stantz, W. Stephens, J. Sturrock, L. Tang, B. Tippens, R. E. Tribble, X.‐L. Tu, L. A. Van Ausdeln, W. vonWitsch, D. Whitehouse, C. Wilkinson, B. Wright, S. C. Wright, Y. Zhang, W. Zhou, X.‐G. Zhou, K. O. H. Ziock; MEGA: A search for the decay μ→eγ. AIP Conf. Proc. 10 July 1995; 338 (1): 789–792. https://doi.org/10.1063/1.48450 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAIP Publishing PortfolioAIP Conference Proceedings Search Advanced Search |Citation Search

All large accelerator control systems eventually outlast the technologies with which they were built. This has happened several times during the lifetime of the accelerators at Los Alamos in the LAMPF/PSR beam delivery complex. Most recently, the EPICS control system has been integrated with the existing LAMPF and PSR control systems. In this paper, we discuss the provisions that were made to provide uniform and nearly transparent sharing of data among the three control systems. The data sharing mechanisms have now been in use during a very successful beam production period. We comment on the successes and failures of the project and indicate the control system properties that make such sharing possible.

The MEGA experiment, which is a search for the decay murarregamma with a branching ratio sensitivity of about 10-13, employs highly modular, fast detectors, state-of-the-art electronics, and a staged trigger with on-line filters. The detectors are contained in a 1.5-T solenoidal field produced by a superconducting magnet. Positrons are confined to the central region and are measured by a set of thin MWPCs. Photons are measured by one of four layers of pair spectrometers in the outer region. Most aspects of the design have been validated in engineering runs; data taking will begin in 1990 with much of the electron arm and one pair spectrometer layer installed.