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An intelligent inspection and survey robot

Description: Large quantities of mixed and low-level radioactive waste contained in 55-, 85-, and 110-gallon steel drums are stored at Department of Energy (DOE) warehouses located throughout the United States. The steel drums are placed on pallets and stacked on top of one another, forming a column of drums ranging in heights of one to four drums and up to 16 feet high. The columns of drums are aligned in rows forming an aisle approximately three feet wide between the rows of drums. Tens of thousands of drums are stored in these warehouses throughout the DOE complex. ARIES (Autonomous Robotic Inspection Experimental System), is under development for the DOE to survey and inspect these drums. The robot will navigate through the aisles and perform an inspection operation, typically performed by a human operator, making decisions about the condition of the drums and maintaining a database of pertinent information about each drum.
Date: December 1, 1995
Creator: Byrd, J.S.
Partner: UNT Libraries Government Documents Department

A robotic inspector for low-level radioactive waste

Description: The Department of Energy has low-level radioactive waste stored in warehouses at several facilities. Weekly visual inspections are required. A mobile robot inspection system, ARIES (Autonomous Robotic Inspection Experimental System), has been developed to survey and inspect the stored drums. The robot will travel through the three- foot wide aisles of drums stacked four high and perform a visual inspection, normally performed by a human operator, making decisions about the condition of the drums and maintaining a database of pertinent information about each drum. This mobile robot system will improve the quality of inspection, generate required reports, and relieve human operators from low-level radioactive exposure.
Date: June 1, 1996
Creator: Byrd, J.S. & Pettus, R.O.
Partner: UNT Libraries Government Documents Department

Low-level stored waste inspection using mobile robots

Description: A mobile robot inspection system, ARIES (Autonomous Robotic Inspection Experimental System), has been developed for the U.S. Department of Energy to replace human inspectors in the routine, regulated inspection of radioactive waste stored in drums. The robot will roam the three-foot aisles of drums, stacked four high, making decisions about the surface condition of the drums and maintaining a database of information about each drum. A distributed system of onboard and offboard computers will provide versatile, friendly control of the inspection process. This mobile robot system, based on a commercial mobile platform, will improve the quality of inspection, generate required reports, and relieve human operators from low-level radioactive exposure. This paper describes and discusses primarily the computer and control processes for the system.
Date: June 1, 1996
Creator: Byrd, J.S. & Pettus, R.O.
Partner: UNT Libraries Government Documents Department

Final project report on arsenic biogeochemistry in the Clinch River and Watts Bar Reservoir: Volume 2, Quality assurance/quality control summary report for arsenic biogeochemistry in the Clinch River and Watts Bar Reservoir. Environmental Restoration Program

Description: Arsenic contamination was studied in the Clinch River/Watts Bar Reservoir (CR/WBR) system downstream from the US Department of Energy`s Oak Ridge Reservation (ORR). Arsenic is of particular interest and concern because (1) it occurs commonly in coal-bearing rock and waste products such as fly ash associated with the burning of coal, (2) it is classified as a Class A carcinogen by the US Environmental Protection Agency, and (3) disposal of fly ash, both on and off the ORR, may have contaminated surface water and sediments in the Clinch River and Watts Bar Reservoir. The present study dffers from previous reports on arsenic concentrations in the CR/WBR system in the use of much more sensitive and precise processing and analytical techniques to measure arsenic species (arsenate, arsenite, and organic arsenic) at levels well below the ecological and human health risk screening criteria. The absolute detection limits using these techniques are approximately 20 to 40 pmol/L or 0.0015 to 0.003 {mu}g/L.
Date: April 1, 1995
Creator: Newman, K.A.; Ford, C.J. & Byrd, J.T.
Partner: UNT Libraries Government Documents Department

A damping ring design for the SLAC Next Linear Collider

Description: In this paper, we describe the design of the main damping rings and the positron pre-damping ring for the SLAC Next Linear Collider, a future linear collider with a center-of-mass energy of 0.5 to 1.5 TeV. The rings will operate at an energy of 2 GeV with a maximum repetition rate of 180 Hz. The normalized extracted beam emittances are {gamma}{epsilon}{sub x} = 3 mm-mrad and {gamma}{epsilon}{sub y} = 0.03 mm-mrad. To provide the necessary damping, the rings must damp multiple trains of bunches. Thus, the beam current is large, roughly 1 A. We will present the optical layout, magnet designs, and RF systems, along with the dynamic aperture and required alignment tolerances; collective effects will be discussed in another paper.
Date: May 1, 1995
Creator: Raubenheimer, T.O.; Byrd, J. & Corlett, J.
Partner: UNT Libraries Government Documents Department

Nonlinear longitudinal dynamics studies at the ALS

Description: We present an account of our efforts to understand unexpected observations in the course of performing measurements of the longitudinal beam transfer function. As the amplitude of the excitation was increased, we observed a notch in the middle of the peak amplitude response of the transfer function. Our observations are explained by a bifurcation in the amplitude due to the nonlinearity of the oscillations, demonstrated by measurements of the longitudinal bunch profile using a streak camera.
Date: May 1, 1997
Creator: Byrd, J.M.; Cheng, W.H. & Zimmermann, F.
Partner: UNT Libraries Government Documents Department

ALS-N - A candidate for a next-generation synchrontron light-source

Description: Judging from the experiments currently being pursued at the ALS, there is already a compelling case to be made for considering a future synchrotron radiation source that has a higher beam brightness than the third-generation facilities. For example, a large, and growing fraction of the ALS scientific program is based on soft x-ray microscopy experiments in materials science. Currently these experiments use high-brightness undulator radiation, on beam lines that are already oversubscribed. Dedicated beam lines from bend magnet sources would be useful for these techniques if the source brightness could be pushed to {approx}2{circ}10{sup 16} photons/(s {circ} mm{sup 2} {circ} mrad{sup 2} {circ} 0.1%b.w.), i.e., a factor of 20-100 higher (depending on wavelength), than currently available at the ALS. Another growing class of experiments uses microfocused beams for microanalysis, microdiffraction, microEXAFS, microXPS, and microNEXAFS. These are classic brightness experiments, but even at the high ALS brightnesses, require long exposure times. Finally there is a requirement to get to {approx}2 keV in the fundamental peak of the undulator spectrum, to access most transition- metal L-edges, and the rare-earth M-edges. This could be achieved with a machine energy of 2.5-3.0 GeV. An alternative strategy is to go to smaller gaps with a shorter period undulator - which is compatible with lower emittance beams.
Date: May 1, 1997
Creator: Jackson, A.; Byrd, J. & Decking, W.
Partner: UNT Libraries Government Documents Department

Controlling the vertical mode coupling instability with feedback in the ALS

Description: The authors present the results of experiments to control the mode coupling instability in the vertical direction using a feedback system. Presently, they can raise the instability threshold from {approximately} 20 mA to 35 mA. The maximum current threshold is reached when the feedback is operated in a resistive mode.
Date: January 1, 1997
Creator: Byrd, J. & Barry, W.
Partner: UNT Libraries Government Documents Department

Observations of collective effects at the Advanced Light Source

Description: We present a summary of measurements of single beam collective effects in the Advanced Light Source (ALS). We describe measurements of coupled-bunch instabilities, including some recent results using the newly commissioned feedback systems and the results of an initial search for the fast ion instability. Single bunch effects include bunch lengthening, energy spread increase, HOM loss measurements, head-tail damping rates, current dependent tune shifts, and transverse mode coupling instability threshold. The longitudinal measurements are consistent with a broadband impedance {vert_bar}{Zeta}{sub {parallel}}/{eta}{vert_bar}{sub eff} = 0.22{plus_minus}0.07 {Omega} and transverse measurements indicate broadband impedances of {Zeta}{sub y,eff} = 155 k{Omega}/m and Z{sub x,eff} = 58 k{Omega}/m.
Date: October 1, 1995
Creator: Byrd, J.M.; Barry, W.; Corlett, J.N.; Fox, J. & Teytelman, D.
Partner: UNT Libraries Government Documents Department

Demonstration of Femtosecond-Phase Stabilization in 2 km OpticalFiber

Description: Long-term phase drifts of less than a femtosecond per hour have been demonstrated in a 2 km length of single-mode optical fiber, stabilized interferometrically at 1530 nm. Recent improvements include a wide-band phase detector that reduces the possibility of fringe jumping due to fast external perturbations of the fiber and locking of the master CW laser wavelength to an atomic absorption line. Mode-locked lasers may be synchronized using two wavelengths of the comb, multiplexed over one fiber, each wavelength individually interferometrically stabilized.
Date: June 1, 2007
Creator: Staples, J.W.; Wilcox, R. & Byrd, J.M.
Partner: UNT Libraries Government Documents Department

Commissioning of the advanced light source dual-axis streak camera

Description: A dual-axis camera, Hamamatsu model C5680, has been installed on the Advanced Light Source photon-diagnostics beam-line to investigate electron-beam parameters. During its commissioning process, the camera has been used to measure single-bunch length vs. current, relative bunch charge in adjacent RF buckets, and bunchphase stability. In this paper the authors describe the visible-light branch of the diagnostics beam-line, the streak-camera installation, and the timing electronics. They will show graphical results of beam measurements taken during a variety of accelerator conditions.
Date: May 1997
Creator: Hinkson, J.; Keller, R. & Byrd, J.
Partner: UNT Libraries Government Documents Department

An intelligent inspection and survey robot

Description: Large quantities of mixed/low-level radioactive waste contained in 55-, 85-, and 110-gallon steel drums are stored at DOE warehouses throughout US. The steel drums are placed on pallets and stacked on top of one another, forming a column of drums ranging in heights of one to five drums and up to 16 feet. The columns of drums are aligned in rows forming aisles about 3 feet wide between the rows of drums. Many tens of thousands of drums are stored in these warehouses. ARIES (Autonomous Robotic Inspection Experimental System) is under development for DOE to survey and inspect these drums. The mobile robot will autonomously navigate through the warehouse and the aisles and perform an inspection operation, typically performed by a human operator, making decisions about the condition of the drums and maintaining a database of pertinent information about each drum.
Date: December 31, 1996
Creator: Byrd, J.S.
Partner: UNT Libraries Government Documents Department

A Collection of Complex Permittivity and Permeability Measurements

Description: We present the results of measurements of the complex permittivity and permeability over a frequency range of 0.1-5.1 GHz for a range of microwave absorbing materials used in a variety of accelerator applications. We also describe the automated measurement technique which uses swept-frequency S-parameter measurements made on a strip transmission line device loaded with the material under test.
Date: February 1, 1993
Creator: Barry, W.; Byrd, J.; Johnson, J. & Smithwick, J.
Partner: UNT Libraries Government Documents Department

The TE Wave Transmission Method for Electron Cloud Measurements at Cesr-TA

Description: We report on the optimization of TE Wave measurements at the Cesr-TA ring at Cornell University. The CESR storage ring is currently used as a test bed for technologies to be used in the damping rings of the International Linear Collider. The TE Wave measurement method utilizes capacitive buttons (BPMs) in the ring to excite and detect a propagating electromagnetic wave corresponding to the beampipe's fundamental TE mode. The presence of low-energy electrons along the wave path changes its propagation characteristics, which can be detected by analyzing the received signal. By choosing the machine fill pattern (gaps and bunch trains length) it is possible to modulate the density of the electron cloud and derive information on its rise and fall times by observing the detected signal spectrum. The possibility of circulating both electron and positron beams in the ring enabled us to separate the contribution of primary photoelectrons, which are independent on the circulating particle nature, from the transverse resonant mechanism, which can increase the primary electron density many times over and which only takes place with a circulating positron beam.
Date: May 4, 2009
Creator: Desantis, S.; Byrd, J.; Sikora, J. & Billing, M.
Partner: UNT Libraries Government Documents Department

Transverse Periodic Beam Loading Effects in a Storage Ring

Description: Uneven beam fill patterns in storage rings, such as gaps in the fill patterns, leads to periodic, or transient loading of the modes of the RF cavities. We show that an analogous effect can occur in the loading of a dipole cavity mode when the beam passes off the electrical center of the cavity mode. Although this effect is small, it results in a variation of the transverse offset of the beam along the bunch train. For ultralow emittance beams, such as optimized third generation light sources and damping rings, this effect results in a larger projected emittance of the beam compared with the single bunch emittance. The effect is particularly strong for the case when a strong dipole mode has been purposely added to the ring, such as a deflecting, or 'crab' cavity. We derive an approximate analytic solution for the variation of the beam-induced deflecting voltage along the bunch train.
Date: May 4, 2009
Creator: Thompson, J.R. & Byrd, J.M.
Partner: UNT Libraries Government Documents Department

Lifetime increase using passive harmonic cavities insynchrotronlight sources

Description: Harmonic cavities have been used in storage rings to increase beam lifetime and Landau damping by lengthening the bunch.The need for lifetime increase is particularly great in the present generation of low to medium energy synchrotron light sources where the small transverse beam sizes lead to relatively short lifetimes from large-angle intrabeam (Touschek) scattering. We review the beam dynamics of harmonic radiofrequency (RF) systems and discuss optimization of the beam lifetime using passive harmonic cavities.
Date: September 22, 2000
Creator: Byrd, J.M. & Georgsson, M.
Partner: UNT Libraries Government Documents Department