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Beam Loss Monitors in the NSLS Storage Rings

Description: Beam loss monitors (BLM) have been used for more than two decades in the VUV ring at the NSLS. These have proved useful for optimizing injection and operation of the ring. Recently similar monitors have been installed in the X-ray ring and are being used to better understand injection, as well as operation of the ring. These units have been compared with the Bergoz BLMs, which have been mostly useful for understanding operating beam losses.
Date: May 4, 2009
Creator: Kramer, S. L. & Fedurin, M.
Partner: UNT Libraries Government Documents Department
open access

Use of a commercial ranging system in field surveys of radioactively contaminated sites

Description: Now, the adaptation of a commercial ranging and tracking system interfaced to these instruments and to an advanced computer graphics system promises another major improvement to the automation of data collection. Contour maps with radiation isopleths and the x-y position of up to eight instrument operators superimposed thereon can be displayed in near real time. A bidirectional data link offers a further improvement in simulation of, and training for, field surveys since previously collected or computer simulated radiation data as a function of position can be transmitted back to the same survey instrument and displayed to the operator in a manner indistinguishable from real-time data. Additionally, simulated instrument malfunctions such as low battery, detector failure, or total failure can be commanded to occur to evaluate operator response to unusual occurrences under the stress of field conditions. This training mode will greatly improve the ability to simulate situations and to train and evaluate operations personnel while eliminating the need to use special sites and potentially hazardous contamination simulants as are used now.
Date: January 1, 1984
Creator: Worth, G.M.; Crowell, J.M.; Meddles, A.D.; Jarrett, J.D.; Wolf, M.A.; Umbarger, C.J. et al.
Partner: UNT Libraries Government Documents Department
open access

Operational problems with radiation survey meters - The University and Accelerator perspectives

Description: This article describes problems encountered with commercial survey meters. The desired qualities of such instruments for use around accelerators are listed. Attempts to meet the accelerator monitoring needs by modifying commercial instruments and by in-house research and development are described.
Date: June 1, 1984
Creator: McCall, R.C.
Partner: UNT Libraries Government Documents Department
open access

QUAD FAMILY CENTERING.

Description: It is well known that beam position monitors (BPM) utilizing signals from pickup electrodes (PUE) provide good resolution and relative accuracy. The absolute accuracy (i.e. position of the orbit in the vacuum chamber) is not very good due to the various reasons. To overcome the limitation it was suggested to use magnetic centers of quadrupoles for the calibration of the BPM [1]. The proposed method provides accuracy better then 200 microns for centering of the beam position monitors using modulation of the whole quadrupole family.
Date: November 1, 2005
Creator: PINAYEV, I.
Partner: UNT Libraries Government Documents Department
open access

The response of survey meters to pulsed radiation fields

Description: The response of most survey meters to steady radiation fields is fairly well known and documented. However, hardly any data is available in the literature regarding the response of these instruments to pulsed radiation. Pulsed radiation fields are encountered, e.g., in the vicinity of linear electron accelerators or klystrons. An instrument that ordinarily responds well to the average dose rate spread out evenly in time may not be able to cope with such a high dose rate. Instruments which have long dead times such as Geiger Mueller and proportional counters tend to become saturated in such fields and only count repetition rate. Ionization chambers are less influenced, however, they must be operated with adequate voltage to overcome recombination losses. Scintillation survey meters may become non-linear at higher dose rates for pulsed radiation because the photomultiplier cannot handle the instantaneous currents that are required. Because of the need to test the response of different radiation detection instruments to pulsed fields, a pulsed x-ray facility has been built (I/sub p/87). A brief description of this facility is given along with tests of several different instruments. 5 refs., 4 figs., 1 tab.
Date: November 1, 1987
Creator: McCall, R.C. & Ipe, N.E.
Partner: UNT Libraries Government Documents Department
open access

Performance testing of Eberline Alpha 6 and Alpha 6A continuous air monitors

Description: Eberline Alpha 6 and Alpha 6A continuous air monitors (CAMs) were tested against the performance criteria of the International Electrotechnical Commission standard 761-6, ``Equipment for Continuously Monitoring Radioactivity in Gaseous Effluents, Part 6: Specific Requirements for Transuranic Aerosol Effluent Monitors``, and against ANSI N42.17B, ``Performance Specification Health Physics Instrumentation--Occupational Airborne Radioactivity Monitoring Instrumentation``. The performance criteria require the CAM`s response to a radioactive source to remain within a tolerance while the CAM is exposed to an external influence such as temperature, electromagnetic fields, or ionizing radiations. The CAMs complied within specified tolerances with a majority of the performance specifications. The most significant problems with CAM performance were noted during exposures to external nonionizing radiation fields (radio frequency fields). At numerous frequencies, the CAMs did not respond to radioactive material in the filter holder. At other frequencies and in some orientations, the CAMs overresponded by orders of magnitude. In addition to sensitivity to external nonionizing radiation fields, the CAMs exhibited sensitivity to electrostatic discharges.
Date: January 1, 1998
Creator: Johnson, M. L.
Partner: UNT Libraries Government Documents Department
open access

Beta-energy response of the Eberline RO-7 survey instrument

Description: An RO-7 radiation survey instrument was obtained from the Eberline Instrument Corporation to use in a study of the beta dose rates from the Godiva IV Critical Assembly at Los Alamos National Laboratory. A limited evaluation of the instrument was performed, and its energy dependence for beta particles was determined. The RO-7 instrument is a hand-held, cutie-pie-style survey meter with a liquid crystal digital readout. The instrument is available with three interchangeable ion chamber probes, although we used only the midrange probe (RO-7-BM) in this study. The midrange probe has a full-scale range of 199.9 R/h and a resolution of 0.1 R/h. The ion chamber has a 1-in.-diameter entry window 2 mils thick (approx. 7 mg/cm/sup 2/) of aluminized mylar. The chamber is lined with phenolic nominally 1/8 in. thick. The housing is nominally 60 mils thick. The chamber's internal dimensions are 1-in. diameter x 0.6-in. length (2.5 cm x 1.5 cm) with a sensitive volume of 7 cm/sup 3/. The beta shield is a plastic cap (approx. 1000 mg/cm/sup 2/) over the beta window and is held in place over the probe by an O-ring. The overall dimensions of the basic probe are 1.5 in. x 4.2 in. The weight of the instrument with the midrange probe is 3.2 pounds (1.5 kg). The batteries are three 9-V and two 30-V cells with an operating lifetime of 160 hours (for the 9-V cells). The overall unit is 9.5 in. high, 4.25 in. wide and 13.5 in. long when the probe is attached.
Date: October 10, 1982
Creator: Hankins, D.E.
Partner: UNT Libraries Government Documents Department
open access

Resolving two beams in beam splitters with a beam position monitor

Description: The beam transport system for the Advanced Hydrotest Facility (AHF) anticipates multiple beam splitters. Monitoring two separated beams in a common beam pipe in the splitter sections imposes certain requirements on diagnostics for these sections. In this note we explore a two-beam system in a generic beam monitor and study the feasibility of resolving the positions of the two beams with a single diagnostic device. In the Advanced Hydrotest Facility (AHF), 20-ns beam pulses (bunches) are extracted from the 50-GeV main proton synchrotron and then are transported to the target by an elaborated transport system. The beam transport system splits the beam bunches into equal parts in its splitting sections so that up to 12 synchronous beam pulses can be delivered to the target for the multi-axis proton radiography. Information about the transverse positions of the beams in the splitters, and possibly the bunch longitudinal profile, should be delivered by some diagnostic devices. Possible candidates are the circular wall current monitors in the circular pipes connecting the splitter elements, or the conventional stripline BPMs. In any case, we need some estimates on how well the transverse positions of the two beams can be resolved by these monitors.
Date: January 1, 2002
Creator: Kurennoy, S. (Sergey)
Partner: UNT Libraries Government Documents Department
open access

Simple MCA supports a variety of applications

Description: A greatly enhanced version of the Violinist I, Simple Multichannel analyzer has been developed at Los Alamos. The new instrument includes a more powerful microprocessor, more memory, and a sophisticated set of I/O devices. The combination of these features allow the same basic electronics package to function in a variety of smart sophisticated monitoring instruments. Only the packaging, detector, and software need be changed to change the instrument from a field survey instrument for Pu contamination to a continuous air monitor to a neutron dosimeter. This instrument should spawn a new generation of user-friendly, highly effective instrumentation.
Date: January 1, 1984
Creator: Wolf, M. A. & Staley, H. C.
Partner: UNT Libraries Government Documents Department
open access

Timing Jitter Characterization at the NSLS SDL

Description: Two novel timing jitter measurement techniques with a 100 fs resolution are presented in this paper. The first technique based on the Schottky effect, is used to measure the timing jitter between the photoinjector drive laser and the RF system; and it was employed to characterize the environment effects on the timing jitter. The I/Q beam monitor based on a stripline beam position monitor (BPM) is used to characterize the electron beam arrival time jitter.
Date: May 4, 2009
Creator: Qian,H.; Hidaka, Y.; Murphy, J. B.; Podobedov, B.; Seletskiy, Shen, Y.; Yang, X. et al.
Partner: UNT Libraries Government Documents Department
open access

Noise control of radiological monitoring equipment

Description: Although vacuum pumps on continuous air monitors (CAMs) do not produce noise levels above regulatory limits, engineering controls were used to establish a safer work environment. Operations performed in areas where CAMs are located are highly specialized and require precision work when handling nuclear materials, heavy metals, and inert gases. Traditional methods for controlling noise such as enclosing or isolating the source and the use of personal protection equipment were evaluated. An innovative solution was found by retrofitting CAMs with air powered multistage ejectors pumps. By allowing the air to expand in several chambers to create a vacuum, one can eliminate the noise hazard altogether. In facilities with adequate pressurized air, use of these improved ejector pumps may be a cost-effective replacement for noisy vacuum pumps. A workplace designed or engineered with noise levels as low as possible or as close to background adds to increased concentration, attention to detail, and increased production.
Date: December 31, 1998
Creator: Rubick, R.D.; Stevens, W.W. & Burke, L.L.
Partner: UNT Libraries Government Documents Department
open access

RF systems for the betatron-node scheme experiment at LBNL

Description: Two-beam accelerators based upon relativistic klystrons (RK's) have been proposed as power sources for future generation electron-positron linear colliders. These drivers are known to suffer from several transverse beam-breakup (BBU) instabilities. A program to study a particular technique (the 'betatron node scheme') of ameliorating the high frequency BBU is under way at LBL. Central to this study are the pillbox RF cavities and RF beam position monitors (BPM's) employed. This paper discusses the design, fabrication, and testing of the RF components. Details of the signal processing and analysis will be presented.
Date: June 22, 2001
Creator: Lidia, Steven M.; De Santis, Stefano & Houck, Timothy
Partner: UNT Libraries Government Documents Department
open access

Non-Intrusive Load Monitoring Assessment: Literature Review and Laboratory Protocol

Description: To evaluate the accuracy of NILM technologies, a literature review was conducted to identify any test protocols or standardized testing approaches currently in use. The literature review indicated that no consistent conventions were currently in place for measuring the accuracy of these technologies. Consequently, PNNL developed a testing protocol and metrics to provide the basis for quantifying and analyzing the accuracy of commercially available NILM technologies. This report discusses the results of the literature review and the proposed test protocol and metrics in more detail.
Date: July 1, 2013
Creator: Butner, R. Scott; Reid, Douglas J.; Hoffman, Michael G.; Sullivan, Greg & Blanchard, Jeremy
Partner: UNT Libraries Government Documents Department
open access

MPX: software for multiplexing hardware performance counters in multithreaded programs

Description: Hardware performance counters are CPU registers that count data loads and stores, cache misses, and other events. Counter data can help programmers understand software performance. Although CPUs typically have multiple counters, each can monitor only one type of event at a time, and some counters can monitor only certain events. Therefore, some CPUs cannot concurrently monitor interesting combinations of events. Software multiplexing partly overcomes this limitation by using time sharing to monitor multiple events on one counter: However; counter multiplexing is harder to implement for multithreaded programs than for single-threaded ones because of certain difficulties in managing the length of the time slices. This paper describes a software library called MPX that overcomes these difficulties. MPX allows applications to gather hardware counter data concurrently for any combination of countable events. MPX data are typically within a few percent of counts recorded without multiplexing.
Date: January 8, 2001
Creator: May, J M
Partner: UNT Libraries Government Documents Department
open access

Quantification of surface contamination: principles and applications

Description: The applications discussed in this paper underscore the usefulness and versatility of molecular luminescence spectroscopy as an efficient surface detection technique. The technique can be used not only as a qualitative characterization method, but also as a quantitative analytical tool to detect trace contaminants on surfaces. Recent advances in instrumentation and methodology have expanded the applicability of surface luminescence into many new problem areas. Trace organics are emphasized here.
Date: January 1, 1982
Creator: Vo-Dinh, T.
Partner: UNT Libraries Government Documents Department
open access

Remote acquisition of gamma-ray pulse height spectra

Description: The acquisition of pulse height spectra data in the industrial environment has traditionally evolved along two paths. The first required the transporting of a radioactive sample from the place of production to a computer system for counting and analysis. This method results in a degradation of the data due to the time delay between sample production and subsequent counting. The second path was taken to count the sample at the place of production and transport the data in the form of paper or magnetic tape to a computer for analysis. Automation of the traditional methods is usually impractical. This paper describes two methods of remote data acquistion developed at the Idaho National Engineering Laboratory which were formulated to mechanize the complete process from data gathering to analysis. Both methods utilize voice grade telephone links between the data gathering device and a PDP-9 computer. The two methods differ in the type of device used to acquire the data. The first is a completely hardwired system. The second is a computer based system utilizing a PDP-8/E. Differences between the two systems are described and evaluations made as to cost versus versatility. (auth)
Date: January 1, 1975
Creator: Killian, E.W. & Heath, R.L.
Partner: UNT Libraries Government Documents Department
open access

Determination of the beta energy (E/sub max/) using thin window instruments

Description: The use of simple survey instruments for beta-energy analysis is complicated by large differences that exist in the beta spectra shapes. These spectral shapes are often complex and change continuously as the betas are absorbed in air. Changes are also caused by absorbing material between the source and the detector. One may frequently encounter a combination of beta energies, either from multiple emissions from a single isotope or from several isotopes in the sample being evaluated. There may also be monoenergetic conversion electrons present in the sample or low-energy X rays which are absorbed in a similar fashion to betas. Obviously, a complete analysis of compelx beta spectra cannot be performed using only survey instruments. We present two methods which will give the approximate E/sub max/ of the beta energy responsible for the most significant portion of the beta dose. Either technique should give adequate information about the beta spectra to provide necessary guidance for the health physics evaluation of the exposure.
Date: August 12, 1983
Creator: Hankins, D.E.
Partner: UNT Libraries Government Documents Department
open access

Definition and means of maintaining the room continuous air monitors portion of the plutonium finishing plant (PFP) safety envelope

Description: Room Continuous Air Monitors (CAMs) are used in areas where there is potential for dispersible radioactive material. These CAMs provide audible and visual alarms to warn personnel of an increase in airborne radioactivity.
Date: May 20, 1999
Creator: WHITE, W.F.
Partner: UNT Libraries Government Documents Department
open access

Construction and operation of the surface contaminant detector Mod II. [Non-radioactive contamination]

Description: This report contains detailed construction and operating instructions, a parts list, and cost estimates for a surface contaminant detector. The instrument is sensitive to the condensible contaminant content of environments and has been used for monitoring industrial facilities where contaminant sensitive parts are processed.
Date: March 1, 1976
Creator: Cuthrell, Robert E.; Nogle, Vaughn D. & Tipping, Donald W.
Partner: UNT Libraries Government Documents Department
open access

A Toroidal Charge Monitor for High-Energy Picosecond Electron Beams

Description: A monitor system suitable for the accurate measurement of the total charge of a 2-ps 28.5 GeV electron beam over a large dynamic range is described. Systematic uncertainties and results on absolute calibration, resolution, and long-term stability are presented.
Date: March 28, 2007
Creator: Simmons, Robert H. & Ng, Johnny S.T.
Partner: UNT Libraries Government Documents Department
open access

PACE and the Federal Housing Finance Agency (FHFA)

Description: The FHFA regulates Fannie Mae, Freddie Mac, and the 12 Federal Home Loan Banks (the government-sponsored enterprises - GSEs). On June 18, 2009, James B. Lockhart III, then Director of FHFA, released a letter expressing concern about the negative impact of energy loan tax assessment programs (ELTAPs) - also known as Property Assessed Clean Energy (PACE) programs - on both the housing finance system and homeowner program participants. Subsequently, a number of PACE proponents responded to the concerns laid out in the FHFA letter. In early Fall 2009, word circulated that FHFA was planning to follow its June letter with guidance to other agencies, possibly including Fannie Mae and Freddie Mac, discouraging them from buying loans on properties subject to PACE-type assessment liens. This triggered a second round of stakeholder letters, several of which were addressed to President Obama. On October 18, 2009, the White House, in what some believe was an attempt to obviate the need for FHFA guidance, released a Policy Framework for PACE Financing Programs that outlined best practices guidance for homeowner and lender protection. As of February 2010, FHFA and the GSEs have agreed to monitor PACE programs and work with stakeholders and the Administration to consider additional guidance beyond the Policy Framework and to collect more information on PACE program efficacy and risks. A summary of the communications timeline and highlights of the communications are provided.
Date: March 17, 2010
Creator: Zimring, Mark & Fuller, Merrian
Partner: UNT Libraries Government Documents Department
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