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Beam Energy and Diameter Diagnostics for ASD Scorpius Commissioning
E. R. Scott;T. Atencio;J. Castaneda;B. Frogget;S. Haque;R. Hibbard;M. A. Jaworski;D. C. Moir;V. Romero;J. Schillig;Z. C. Shaw;S. Smith;K. Walters;M. E. Weller;S. Baker;D. Clayton;T. J. Burris-Mog
2022 IEEE International Conference on Plasma Science (ICOPS)
Year: 2022 | Conference Paper |
The commissioning phase of the ASD Scorpius accelerator, a multi-pulse linear induction accelerator, is already underway. To confirm that the accelerator meets requirements, several diagnostics are under development specifically for commissioning. A permanent magnet momentum spectrometer based on a system used at the Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility will provide time-resol...Show More
Measurement of intense continuous and flash radiographic sources with Compton spectrometers
A. Gehring;M. Espy;T. Burris-Mog;C. Gautier;T. Haines;D. Moir;R. Shurter
2017 IEEE 21st International Conference on Pulsed Power (PPC)
Year: 2017 | Conference Paper |
Our team at Los Alamos National Laboratory has successfully employed Compton spectrometers to measure the x-ray spectra of intense radiographic sources, both continuous and flash. In this method, a collimated beam of x-rays incident on a convertor foil ejects Compton electrons. A collimator may be inserted into the entrance of the spectrometer to select the angular acceptance of the forward-scatte...Show More
Characterizing the photon spectrum generated in the DARHT AXIS-I diode
J.E. Coleman;D.C. Moir;C.A. Ekdahl;J.B. Johnson;B.T. McCuistian;M.T. Crawford
An array of photon diagnostics have been deployed on a high power relativistic electron beam diode. Surface flashover of a carbon fiber velvet cathode generates a discharge from which electrons are accelerated through a 17.8 cm diode. This discharge is assumed to be a hydrocarbon mixture. A small portion of the off energy electrons accelerated during the rise and fall of the 80 ns FWHM pulse impac...Show More
Characterizing the photon spectrum in the DARHT Axis-I diode
J.E. Coleman;J.B. Johnson;B.T. McCuistian;D.C. Moir;M.T. Crawford
An array of photon diagnostics have been deployed on a high power relativistic electron beam diode. Surface flashover of a carbon fiber velvet cathode generates a discharge from which electrons are accelerated through a 17.8 cm diode. This discharge is assumed to be a hydrocarbon mixture. A small portion of the off energy electrons (1-3 MeV) accelerated during the rise and fall of the 80 ns FWHM p...Show More
PPPS-2013: Design of a paraxial inverse Compton scattering diagnostic for an intense relativistic electron beam
J. E. Coleman;J. A. Oertel;C. A. Ekdahl;D. Shaw;T. N. Archuleta;D. C. Moir;B. T. McCuistian;Y. Platonov;B. Ehlers;R. J. Spaulding;A. Meidinger
2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)
Year: 2013 | Conference Paper |
An inverse Compton scattering diagnostic is currently being developed for a 60 ns, intense relativistic electron bunch with an energy of 19.8 MeV and nominal current of 1.7 kA. The principal purpose of this diagnostic is to provide a measurement of the 6-D phase space distribution of the electron beam in a single shot without disrupting its axial propagation. The electron beam is intercepted by a ...Show More
PPPS-2013: Explosive emission and gap closure from a relativistic electron beam diode
J. E. Coleman;D. C. Moir;B. T. McCuistian;C. A. Ekdahl;J. B. Johnson;M.T. Crawford
2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)
Year: 2013 | Conference Paper |
Summary form only given. Explosive emission cathode studies are currently being conducted on a high power relativistic electron beam diode. A black velvet cathode is driven with a 75 Ohm graded transmission line which provides a 3.8 M V, 60 ns (FWHM) pulse across a fixed A-K gap of 17.5 cm. Cathode sizes range from 1.9-7 cm with space-charge limited currents of 0.26-3 kA. The principal objective o...Show More
Explosive emission and gap closure from a relativistic electron beam diode
J. E. Coleman;D. C. Moir;C. A. Ekdahl;J. B. Johnson;B. T. McCuistian;M. T. Crawford
Explosive emission cathode studies are currently being conducted on a high power relativistic electron beam diode. A black velvet cathode is driven with a 75 Ohm graded transmission line, which provides a 3.8 MV, 80 ns (FWHM) pulse across a fixed A-K gap of 17.8 cm. Cathode sizes range from 1.9-7 cm with space-charge limited currents of 0.26-3 kA. The principal objective of these experiments is to...Show More
Design of a paraxial inverse Compton scattering diagnostic for an intense relativistic electron beam
J. E. Coleman;J. A. Oertel;C. A. Ekdahl;D. Shaw;T. N. Archuleta;D. C. Moir;B. T. McCuistian;M. T. Crawford;Y. Platonov
2013 19th IEEE Pulsed Power Conference (PPC)
Year: 2013 | Conference Paper |
An inverse Compton scattering diagnostic is currently being developed for an 80 ns, intense relativistic electron bunch with an energy of 19.8 MeV and nominal current of 1.7 kA. The principal purpose of this diagnostic is to provide a measurement of the 6-D phase space distribution of the electron beam in a single shot without disrupting its axial propagation. The electron beam is intercepted by 4...Show More
Spot size measurement of the DARHT First Axis radiographic source
Brian T. McCuistian;Evan Rose;Dave Moir;Howard Bender;Carl Carlson;Craig Hollabaugh
2008 IEEE 35th International Conference on Plasma Science
Year: 2008 | Conference Paper |
Summary form only given. DARHT is the dual axis radiographic hydrodynamic test facility at Los Alamos National Laboratory. The radiographic spot size is a critical parameter in the performance of the facility to produce quality radiographs. Images of the radiographic spot of the first axis of the DARHT facility have been acquired using a pinhole geometry, scintillator, and CCD framing cameras. The...Show More
DARHT-II commissioning status
B.T. McCuistian;O. Abeyta;P. Aragon;L. Caudill;C. Ekdahl;S. Eversole;D. Dalmans;J. Harrison;E. Jacquez;J. Johnson;H. Kirbie;D. Moir;N. Montoya;K. Nielsen;D. Oro;M. Reed;L. Rodriguez;M. Sanchez;J. Schwaegel;D. Simmons;J. Studebaker;G. Sulliva;C. Swinney;R. Temple;S. Eylon;T. Houck;R. Sturges
Digest of Technical Papers. PPC-2003. 14th IEEE International Pulsed Power Conference (IEEE Cat. No.03CH37472)
Year: 2003 | Conference Paper |
Cited by: Papers (4)
The dual axis radiographic hydrotest facility (DARHT) at Los Alamos National Laboratory produces flash radiographs of hydrodynamic experiments using two linear induction accelerators situated on orthogonal axes. The first axis accelerator is operational and has produced radiographs of hydrodynamic experiments. The second axis accelerator, which is in the commissioning stage, will generate an 18-Me...Show More
DARHT-II commissioning status
B.T. McCuistian;O. Abeyta;P. Aragon;L. Caudill;C. Ekdahl;S. Eversole;D. Dalmans;J. Harrison;E. Jacquez;J. Johnson;H. Kirbie;D. Moir;N. Montoya;K. Nielsen;D. Oro;M. Reed;L. Rodriguez;M. Sanchez;J. Schwaegel;D. Simmons;J. Studebaker;G. Sulliva;C. Swinney;R. Temple;S. Eylon;T. Houck;R. Sturges
Electron beam disruption due to ion release from targets-experimental observations
H.A. Davis;C. Vermare;T.P. Hughes;D.C. Moir;R.T. Olson;W.M. Wood
IEEE Conference Record - Abstracts. 2002 IEEE International Conference on Plasma Science (Cat. No.02CH37340)
Year: 2002 | Conference Paper |
Cited by: Papers (1)
Summary form only given, as follows. A major concern for the new generation radiography facilities like DARHT and AIRIX is that ions or ionized neutrals released from solid surfaces by beam impact can be accelerated and trapped by the beam potential. This time-dependent positive-charge distribution, inside the beam channel, can disrupt the beam. Possible release mechanisms include electron induced...Show More
Electron beam disruption due to ion release from targets-comparison between computer calculations and observations
T.P. Hughes;H.A. Davis;C. Vermare;D.C. Moir;R.T. Olson;W.M. Wood
IEEE Conference Record - Abstracts. 2002 IEEE International Conference on Plasma Science (Cat. No.02CH37340)
Year: 2002 | Conference Paper |
Summary form only given, as follows. Experiments have been performed on the first axis of the DARHT electron beam accelerator to study the effects on the beam of ion emission from surfaces struck by electrons. Calculations using the two-and three-dimensional Lsp particle-in-cell code were performed to compare with experimental results. Two-dimensional calculations, which allow the release of ions ...Show More
The impact of particle desorption on DARHT-II electron beam dynamics
H.A. Davis;F.E. Merrill;D.C. Moir;D.M. Oro;C. Vermare;W.M. Wood;J.M. Elizondo;T.P. Hughes
Summary form only given, as follows. It is well known in the intense beam community that when an intense electron beam raises the surface temperature of a solid target (e.g., electrode or aperture) to 300-400 deg C, that loosely bound adsorbed molecules are rapidly released from the surface often followed by speedy ionization. This can lead to adverse beam or diode behavior. Less well known is tha...Show More
Intense electron beam disruption due to ion release from surfaces
C. Vermare;H.A. Davis;T.P. Hughes;D.C. Moir;R.T. Olson;W.M. Wood
A major concern for the DARHT second axis (2 kA, 18.6 MeV, 2000 ns) is that ions or ionized neutrals released from solid surfaces (e.g., apertures, septum, dumps, and targets) by beam impact can be accelerated and trapped by the beam potential. This positive charge will be electrically attracted to the beam and could disrupt it. To study this, experiments were performed on the DARHT first axis. He...Show More
Intense electron beam disruption due to ion release from surfaces
H.A. Davis;C. Vermare;T.P. Hughes;D.C. Moir;R.T. Olson;W.M. Wood
PACS2001. Proceedings of the 2001 Particle Accelerator Conference (Cat. No.01CH37268)
Year: 2001 | Conference Paper |
Cited by: Papers (1)
A major concern for the DARHT second axis (2 kA, 18.6 MeV, 2000 ns) is that ions or ionized neutrals released from solid surfaces (e.g., apertures, septums, dumps, and targets) by beam impact can be accelerated and trapped by the beam potential. This positive charge could disrupt the beam. To study this, experiments were performed on the DARHT first axis. The beam, focused to a range of diameters,...Show More
DAHRT accelerators update and plans for initial operation
M.J. Burns;B.E. Carlsten;T.J.T. Kwan;D.C. Moir;D.S. Prono;S.A. Watson;E.L. Burgess;H.L. Rutkowski;G.J. Caporaso;Y.-J. Chen;S. Sampayan;G. Westenskow
Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)
Year: 1999 | Conference Paper |
Cited by: Papers (27)
The Dual-Axis Radiographic Hydrodynamics Test (DARHT) facility will use two perpendicular electron linear induction accelerators to produce intense, bremsstrahlung X-ray pulses for flash radiography. We intend to produce measurements containing 3D information with sub-millimeter spatial of the interior features of very dense explosively driven objects. The facility will be completed in two phases ...Show More
Dynamical measurements of plasmas generated by relativistic electrons colliding with metal targets
W.M. Wood;B.L. Wright;D.M. Oro;R.D. Fulton;D.C. Moir;T. Kwan
25th Anniversary, IEEE Conference Record - Abstracts. 1998 IEEE International Conference on Plasma Science (Cat. No.98CH36221)
Year: 1998 | Conference Paper |
Cited by: Papers (1)
Summary form only given. We present data from a series of diagnostics operating on the ITS linear induction accelerator at Los Alamos National Laboratory. Using interferometry, both at optical and microwave frequencies, we are able to characterize the temporal evolution of the plasma parameters when material is ejected from various targets. Concurrent streak camera measurements of X-ray spot size ...Show More
Development and characterization of diamond film and compound metal surface high current photocathodes
R.P. Shurter;D.C. Moir;D.J. Devlin;R.W. Springer;T.A. Archuleta
Proceedings of the 1997 Particle Accelerator Conference (Cat. No.97CH36167)
Year: 1997 | Conference Paper |
High current photocathodes operating in vacuum environments as high as 8/spl times/E-5 torr are being developed at Los Alamos for use in a new generation of linear induction accelerators. We report quantum efficiencies in wide bandgap semiconductors, pure metals and compound metal surface photocathode materials illuminated by ultraviolet laser radiation.Show More
Quadrupole image-current effects in the ITS 6-MeV, 4-kA linac
Proceedings of the 1997 Particle Accelerator Conference (Cat. No.97CH36167)
Year: 1997 | Conference Paper |
Cited by: Papers (1)
The eight accelerating cells for the ITS linear induction accelerator (LIA) are driven with two 50-/spl Omega/ lines at 250 kV for 60 ns. The wall return currents for the 4-kA beam then pass through these lines, generating a weak steady-state quadrupole field of /spl sim/3 G integrated strength on axis, which causes a small asymmetry in the nominally round beam at the linac exit. Beam-dynamics sim...Show More
BBU gain measurements on the ITS 6-MeV, 4-kA linac
Proceedings of the 1997 Particle Accelerator Conference (Cat. No.97CH36167)
Year: 1997 | Conference Paper |
Cited by: Papers (3)
The amplification of transverse beam motion by the ITS eight-cell linear induction accelerator (LIA) was measured with a 4-kA beam at frequencies between 710- and 950-MHz. The 3.75-MeV injector beam was deflected with amplitudes of /spl sim/1 mrad by an RF-driven tunable cavity 84 cm before the linac. The centroid-position waveforms from calibrated B-dot loops were recorded with 5-GS/s digitizers ...Show More
Observation of self-steering effects on the ITS 6-MeV linac
Proceedings of the 1997 Particle Accelerator Conference (Cat. No.97CH36167)
Year: 1997 | Conference Paper |
Cited by: Papers (2)
Beam centroid oscillations were induced in the ITS eightcell linear induction accelerator (LIA) by steering the beam near the entrance, and position measurement were then made at four locations through the linac. Measurements were in good agreement with code predictions, using the nominal accelerator values, for a collimated beam of /spl sim/0.3 kA, but to get reasonable agreement for the full 3-k...Show More
Computational and experimental studies of the beam-target interaction for high-dose, multi-pulse radiography
IEEE Conference Record - Abstracts. 1997 IEEE International Conference on Plasma Science
Year: 1997 | Conference Paper |
Summary form only given. The conversion of an intense relativistic electron beam into X-rays for radiographic imaging is achieved through the bremsstrahlung process of electrons in a target of optimal thickness. To achieve desirable resolution for thick objects, an extremely high-brightness electron beam is used, and a significant amount of beam energy can be deposited in a small area of the targe...Show More
The Integrated Test Stand at Los Alamos National Laboratory (LANL) is addressing issues in high-brightness electron beam generation, acceleration, and transport. The machine consists of a 3 kA, 3.5 MV injector, eight induction acceleration gaps, a drift section and a final-focus magnet which focuses the beam onto diagnostic targets. One of the goals of the program is to test and improve the predic...
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First Page of the Article
Show MoreBeam matching in to the DARHT linac
1992 9th International Conference on High-Power Particle Beams
Year: 1992 | Conference Paper |
Cited by: Papers (1)
The DARHT (Dual-Axis Radiographie Hydro-Test) Facility is a large flash x-ray radiography facility to be built at Los Alamos National Laboratory (LANL). Prototyping of the beam injector and first block of eight accelerating cells is being carried out at the Intermediate Test Stand (ITS) at LANL. We have carried out numerical calculations using particle-in-cell and envelope codes to model initial b...Show More
Technology demonstration for the DARHT Linear Induction Accelerators
M. Burns;P. Allison;J. Downing;D. Moir;G. Caporaso;Y. J. Chen
1992 9th International Conference on High-Power Particle Beams
Year: 1992 | Conference Paper |
Cited by: Papers (2)
The Dual-Axis Radiographic Hydrodynamics Test (DARHT) facility will employ two 16-MeV, 3-kA Linear Induction Accelerators to produce intense, bremsstrahlung x-ray pulses for flash radiography. Technology demonstration of the key accelerator sub-systems is underway at the DARHT Integrated Test Stand (ITS), which will produce a 6-MeV, 3-kA, 60-ns flattop electron beam. We will summarize measurements...Show More
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