74 Matching Results

Search Results

Advanced search parameters have been applied.
in creator/contributor: "Houck, T."  
Results: 1 - 24 next
open access

50 MW X-BAND RF SYSTEM FOR A PHOTOINJECTOR TEST STATION AT LLNL

Description: In support of X-band photoinjector development efforts at LLNL, a 50 MW test station is being constructed to investigate structure and photocathode optimization for future upgrades. A SLAC XL-4 klystron capable of generating 50 MW, 1.5 microsecond pulses will be the high power RF source for the system. Timing of the laser pulse on the photocathode with the applied RF field places very stringent requirements on phase jitter and drift. To achieve these requirements, the klystron will be powered b… more
Date: March 11, 2011
Creator: Marsh, R A; Anderson, S G; Barty, C J; Beer, G K; Cross, R R; Ebbers, C A et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Advanced accelerator theory development

Description: A new accelerator technology, the dielectric wall accelerator (DWA), is potentially an ultra compact accelerator/pulsed power driver. This new accelerator relies on three new components: the ultra-high gradient insulator, the asymmetric Blumlein and low jitter switches. In this report, we focused our attention on the first two components of the DWA system the insulators and the asymmetric Blumlein. First, we sought to develop the necessary design tools to model and scale the behavior of the hig… more
Date: February 9, 1998
Creator: Sampayan, S.E.; Houck, T.L.; Poole, B.; Tishchenko, N.; Vitello, P.A. & Wang, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

BBU design of linear induction accelerator cells for radiography application

Description: There is an ongoing effort to develop accelerating modules for high-current electron accelerators for advanced radiography application. Accelerating modules with low beam-cavity coupling impedances along with gap designs with acceptable field stresses comprise a set of fundamental design criteria. We examine improved cell designs which have been developed for accelerator application in several radiographic operating regimes. We evaluate interaction impedances, analyze the effects of beam struct… more
Date: May 6, 1997
Creator: Shang, C. C.; Chen, Y. J.; Gaporaso, G. J.; Houck, T. L.; Molau, N. E.; Focklen, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Beam breakup calculations for the second axis of DARHT

Description: The accelerator for the second axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility will produce a 4-kA, 20-MeV, 2-{micro}s output electron beam with a design goal of less than 1000 {pi} mm-mrad normalized transverse emittance and less than 0.5-mm beam centroid motion. In order to meet this goal, the beam transport must have excellent optics and the beam breakup instability (BBU) must be limited in growth. Using a number of simulation codes such as AMOS and BREAKUP, we have mod… more
Date: August 20, 1999
Creator: Fawley, William M.; Chen, Y. J. & Houck, T. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Beam Dynamics Experiments in Support of Relativistic Klystrons

Description: Experiments to study beam dynamics for Relativistic Klystrons (RK) are being performed with a 1-MeV, 600-A induction accelerator beam. The RK is a RF Power source based on induction accelerator technology and conventional resonant output structures. Capable of generating 100's of MW/m at frequencies up to K-band, the RK has been proposed as a driver for a future linear collider in one version of a Two-Beam Accelerator. A critical feasibility issue remaining to be demonstrated is suppression of … more
Date: June 3, 2001
Creator: Houck, T & Lidia, S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Beam-Target Interaction Experiments for Bremsstrahlung Converter Applications

Description: The DARHT TI accelerator uses a pulsed high current electron beam and Eiremsstrahlung converter target to generate an intense x-ray source for radiography. For the past several years, we have been performing an investigation of the possible adverse effects of (1) backstreaming ion emission from the Bremsstrahlung converter target and (2) the interaction of the resultant plasma with the electron beam during subsequent pulses. These effects would manifest themselves in a static focusing system as… more
Date: September 28, 2000
Creator: Sampayan, S.; Caporaso, G.; Chen, Y. J.; Falabella, S.; Ho, D.; Houck, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Beam-target interaction experiments for Bremsstrahlung converter applications

Description: The authors are investigating the possible adverse effects of (1) backstreaming ion emission from the Bremsstrahlung converter target and (2) the interaction of the resultant plasma with the electron beam during subsequent pulses for multi-pulse radiography facilities. These effects would primarily manifest themselves in a static focusing system as a rapidly varying x-ray spot. To study these effects, they are conducting beam-target interaction experiments on the ETA-II accelerator (a 6.0 MeV, … more
Date: March 1, 1999
Creator: Buckles, R.; Caparaso, G.; Chen, Y. J.; Crist, C.; Falabella, S.; Houck, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Beam-Target Interaction Experiments for Multipulse Bremsstrahlung Converters Applications

Description: As part of the Dual Axis Radiography Hydrotest Facility, Phase II (DARHT II) multipulse Bremsstrahlung target, we have been performing an investigation of (1) the possible adverse effects of backstreaming ion emission from the Bremsstrahlung converter target and (2) maintaining sufficient target density to ensure dose in latter pulses. Theory predictions show that the first effect would primarily be manifested in the static focusing system as a rapidly varying x-ray spot. From experiments perfo… more
Date: June 18, 2001
Creator: Sampayan, S.; Buckles, R.; Caporaso, G.; Chambers, F. C.; Chen, Y. J.; Falabella, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

CHARACTERIZATION OF A HIGH CURRENT INDUCTION ACCELERATOR ELECTRON BEAM VIA OPTICAL TRANSITION RADIATION FROM DIELECTRIC FOILS

Description: Traditionally, thin metal foils are employed for optical transition radiation (OTR) beam diagnostics but the possibility of shorting accelerator insulating surfaces and modifying accelerating fields are concerns. The successful utilization of dielectric foils in place of metal ones could alleviate these issues but necessitates more understanding of the OTR data for inferring desired beam parameters because of the dielectric's finite permittivity. Additionally, the temperature dependence of the … more
Date: June 13, 2007
Creator: Tang, V; Brown, C & Houck, T
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Choppertron II

Description: We present experimental results of a version of the Choppertron microwave generator designed to work with the high emittance beam of the Advanced Test Accelerator (ATA). Simulations showed that a 800-A, 120 {pi} cm-mrad beam (typical of ATA), could produce 800 MW of rf (11.4 GHz) power using two 12-cell, traveling-wave output structures. Funding contraints prevented final tuning of the modulator system and limited the experiment to 530 MW in narrow pulses. Over 400 MW were extracted from a sing… more
Date: April 25, 1995
Creator: Houck, T.L.; Westenskow, G.A.; Haimson, J. & Mecklenburg, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

DARHT 2 kA Cathode Development

Description: In the campaign to achieve 2 kA of electron beam current, we have made several changes to the DARHT-II injector during 2006-2007. These changes resulted in a significant increase in the beam current, achieving the 2 kA milestone. Until recently (before 2007), the maximum beam current that was produced from the 6.5-inch diameter (612M) cathode was about 1300 A when the cathode was operating at a maximum temperature of 1140 C. At this temperature level, the heat loss was dominated by radiation wh… more
Date: March 9, 2009
Creator: Henestroza, E.; Houck, T.; Kwan, J. W.; Leitner, M.; Miram, G.; Prichard, B. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Design and characterization of a neutralized-transport experiment for heavy-ion fusion

Description: In heavy-ion inertial-confinement fusion systems, intense beams of ions must be transported from the exit of the final focus magnet system through the fusion chamber to hit millimeter-sized spots on the target. Effective plasma neutralization of intense ion beams in this final transport is essential for a heavy-ion fusion power plant to be economically competitive. The physics of neutralized drift has been studied extensively with particle-in-cell simulations. To provide quantitative comparison… more
Date: March 14, 2004
Creator: Henestroza, E.; Eylon, S.; Roy, P. K.; Yu, S. S.; Anders, A.; Bieniosek, F. M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design and Characterization of a Neutralized-Transport Experiment for Heavy-Ion Fusion

Description: In heavy-ion inertial-confinement fusion systems, intense beams of ions must be transported from the exit of the final focus magnet system through the fusion chamber to hit millimeter-sized spots on the target. Effective plasma neutralization of intense ion beams in this final transport is essential for a heavy-ion fusion power plant to be economically competitive. The physics of neutralized drift has been studied extensively with particle-in-cell simulations. To provide quantitative comparison… more
Date: May 24, 2004
Creator: Henderson, E.; Eylon, S.; Roy, P.; Yu, S. S.; Anders, A.; Bieniosek, F. M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design and Simulation of an Anode Stalk Support Insulator

Description: An anode stalk support insulator in a magnetically insulated transmission line was designed and modeled. One of the important design criteria is that within space constraints, the electric field along the insulator surface has to be minimized in order to prevent a surface flashover. In order to further reduce the field on the insulator surface, metal rings between insulator layers were also specially shaped. To facilitate the design process, electric field simulations were performed to determin… more
Date: May 16, 2005
Creator: Wang, L.; Houck, T. & Westenskow, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design consideration of relativistic klystron two-beam accelerator for suppression of beam-break-up

Description: It is demonstrated in this simulation study that by using the scheme of operating rf extraction structures on the betatron nodes of electron drive beam in conjunction with adequate de-Q-ing, appropriate choice of geometries for the rf structures (reducing transverse impedence) and/or staggered tuning we can suppress the overall growth of transverse instabilities to 4 e-folds in a relativistic klystron two-beam accelerator with 200 extraction cavities.
Date: March 1, 1994
Creator: Li, H.; Houck, T. L.; Yu, S. & Goffeney, N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design of a 1-MV induction injector for the Relativistic Klystron Two-Beam Accelerator

Description: A Relativistic Klystron Two-Beam Accelerator (RK-TBA) is envisioned as a rf power source upgrade of the Next Linear Collider. Construction of a prototype, called the RTA, based on the RK-TBA concept has commenced at the Lawrence Berkeley National Laboratory. This prototype will be used to study physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. The first half of the injector, a 1 MeV, 1.2 kA, 300 ns induction electron gun, has been bu… more
Date: May 1, 1997
Creator: Anderson, D.E.; Eylon, S.; Lidia, S.; Reginato, L.; Vanecek, D.; Yu, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design of a High Field Stress, Velvet Cathode for the Flash X-Ray (FXR) Induction Accelerator

Description: A new cathode design has been proposed for the Flash X-Ray (FXR) induction linear accelerator with the goal of lowering the beam emittance. The original design uses a conventional Pierce geometry and applies a peak field of 134 kV/cm (no beam) to the velvet emission surface. Voltage/current measurements indicate that the velvet begins emitting near this peak field value and images of the cathode show a very non-uniform distribution of plasma light. The new design has a flat cathode/shroud profi… more
Date: June 8, 2007
Creator: Houck, T.; Brown, C.; Fleming, D.; Kreitzer, B.; Lewis, K.; Ong, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design of a reacceleration experiment using the Choppertron

Description: The Microwave Source Facility at the Lawrence Livermore National Laboratory is commencing a series of experiments involving reacceleration of a modulated beam alternating with extraction of energy in the form of X-band microwaves. The Choppertron, a high-power microwave generator, is used to modulate a 5-MV, 1-kA induction accelerator beam. The modulated beam is then passed through a series of traveling-wave output structures separated by induction cells. In this paper we report on computer sim… more
Date: January 1, 1993
Creator: Fiorentini, G. M.; Wang, C. & Houck, T. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design of a reacceleration experiment using the Choppertron

Description: The Microwave Source Facility at the Lawrence Livermore National Laboratory is commencing a series of experiments involving reacceleration of a modulated beam alternating with extraction of energy in the form of X-band microwaves. The Choppertron, a high-power microwave generator, is used to modulate a 5-MV, 1-kA induction accelerator beam. The modulated beam is then passed through a series of traveling-wave output structures separated by induction cells. In this paper we report on computer sim… more
Date: January 1, 1993
Creator: Fiorentini, G. M.; Wang, C. & Houck, T. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design of a relativistic Klystron Two-Beam Accelerator Prototype

Description: We are designing an experiment to study physics, engineering, and costing issues of an extended Relativistic Klystron Two-Beam Accelerator (RK-TBA). The experiment is a prototype for an RK-TBA based microwave power source suitable for driving a 1 TeV linear collider. Major components of the experiment include a 2.5-MV, 1.5-kA electron source, a 11.4-GHz modulator, a bunch compressor, and a 8-m extraction section. The extraction section will be comprised of 4 traveling-wave output structures, ea… more
Date: April 1, 1995
Creator: Westenskow, G.; Caporaso, G.; Chen, Y.; Houck, T.; Yu, S.; Chattopadhyay, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design study of a microwave driver for a Relativistic Klystron Two-Beam Accelerator

Description: In two-beam accelerators, the reacceleration of a modulated drive beam can enable high conversion efficiency of electron beam energy to rf energy. However, the stability issues involved with the transport of high current electron beams through rf extraction structures and induction accelerator cells are critical. The author reports on theoretical studies and computer simulations of a two-beam accelerator design using traveling-wave extraction structures. Specific issues addressed include regene… more
Date: May 1, 1993
Creator: Houck, T. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design study of beam dynamics issues for 1 TeV next linear collider based upon the relativistic-klystron two-beam accelerator

Description: A design study has recently been conducted for exploring the feasibility of a relativistic-klystron two-beam accelerator (RK-TBA) system as a rf power source for a 1 TeV linear collider. The author present, in this paper, the beam dynamics part of this study. They have achieved in their design study acceptable transverse and longitudinal beam stability properties for the resulting high efficiency and low cost RK-TBA.
Date: November 1, 1994
Creator: Li, H.; Goffeney, N.; Henestroza, E.; Sessler, A.; Yu, S.; Houck, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
Back to Top of Screen