Showing papers on "Linear particle accelerator published in 1994"

Method and apparatus for patient positioning for radiation therapy

Abstract: A method and apparatus for positioning a patient upon a treatment table of a linear accelerator includes a camera secured to the gantry of the linear accelerator and a plurality of light emitting diodes mounted with respect to the patient which are viewed by the camera.

Transverse particle motion in radio-frequency linear accelerators

Abstract: The transverse motion of a relativistic charged particle in a radio-frequency linear accelerator (rf linac) is examined. The spatially averaged equations of motion are derived for a particle in a periodic accelerating cavity system, and solved exactly in the ultrarelativistic limit. These solutions, along with an impulse treatment of the transients at the entrance and exit of the linac cavities, allow derivation of a linear transport matrix through the cavity. This generalized matrix is improved over previously derived results in that it is applicable to both traveling- and standing-wave structures, allows for arbitrary injection phase and spatial-harmonic content of the rf fields, and is more accurate in approximating the exact charged-particle motion.

Intraoperative electron beam therapy system and facility

Abstract: An electron beam therapy system and a facility for using an electron beam therapy system. In the preferred embodiment, the electron beam therapy system comprises a linear accelerator (16), microwave source (30), and associated electronics disposed in a housing (10). The housing (10) is mounted on a positioning means (50) such as a C-arm to direct the electron beam to the desired site on the patient. The entire housing (10) and positioning means (50) is mobile and may be moved to different locations (71, 72) in the facility. Connectors (77, 78) are provided at the different locations (71, 72) in the facility to connect the electron beam source to a central power source within the facility.

Measurement of the longitudinal asymmetry of a charged particle bunch from the coherent synchrotron or transition radiation spectrum.

Abstract: The shapes of submillimeter long electron bunches at the Cornell linear accelerator have been determined by measuring the coherent far-ir synchrotron and transition radiation spectrum produced by the charge distribution With the aid of a Kramers-Kronig analysis of the spectral data, we show that the longitudinal bunch shape including the asymmetry can be accurately determined

Short wavelength FELs using the SLAC linac

Abstract: Recent technological developments have opened the possibility to construct a device which we call a linac coherent light source (LCLS) (C. Pellegrini et al., Nucl. Instr. and Meth. A 331 (1993) 223; H. Winick et al., Proc. IEEE 1993 Particle Accelerator Conf., Washington, DC, May 1993; C. Pellegrini, Nucl. Instr. and Meth. A 341 (1994) 326; J. Seeman, SPIE Meet. on Electron Beam Sources of High Brightness Radiation, San Diego, CA, July 1993 [1–4]); it would be a fourth-generation light source, with brightness, coherence, and peak power far exceeding other sources. Operating on the principle of the free electron laser (FEL), the LCLS would extend the range of FEL operation to much shorter wavelength than the 240 nm that has so far been reached. We report the results of studies of the use of the SLAC linac to drive an LCLS at wavelengths from about 3 to 100 nm initially and possibly even shorter wavelengths in the future. Lasing would be achieved in a single pass of a low emittance, high peak current, high-energy electron beam through a long undulator. Most present FELs use an optical cavity to build up the intensity of the light to achieve lasing action in a low-gain oscillator configuration. By eliminating the optical cavity, which is difficult to make at short wavelengths, laser action can be extended to shorter wavelengths by self-amplified-spontaneous-emission (SASE), or by harmonic generation from a longer wavelength seed laser. Short wavelength, single pass lasers have been extensively studied at several laboratories and at recent workshops (M. Cornacchia and H. Winick (eds.), SLAC Report 92/02; I. Ben-Zvi and H. Winick (eds.), BNL report 49651 [5,6]). The required low-emittance electron beam can be achieved with recently-developed rf photocathode electron guns (B.E. Carlsten, Nucl. Instr. and Meth. A 285 (1989) 313; J. Rosenzweig and L. Serafini, Proc. IEEE 1993 Particle Accelerator Conf., Washington, DC, 1993 [7,8]). The peak current is increased by about an order of magnitude by compressing the bunch to a lenght of about 0.2 ps (rms). Techniques for beam transport, acceleration, and compression without emittance dilution have been developed at SLAC as part of the linear-collider project (J. Seeman, Advances of Accelerator Physics and Technologies, ed. H. Schopper (World Scientific, Singapore, 1993 [9]). The undulator length required to saturate the laser varies from about 15 m for a 100 nm FEL to about 60 m at 3 nm. Initial experiments, at wavelengths down to about 50 nm are planned using the 25-m long Paladin undulator now located at LLNL. In a proposed future LCLS R&D facility the short wavelength light pulses are distributed to multiple end stations using grazing-incidence mirrors. About 10 14 photons per pulse can be produced at a 120 Hz rate, corresponding to average brightness levels of about 10 21 photons/s/mm 2 /mrad 2 within 0.1% BW and peak brightness levels of about 10 31 photons/s/mm 2 /mrad 2 within 0.1% BW. Peak power levels are several hundred megawatts to several gigawatts. Electron energies required range from about 500 MeV for the 100 nm FEL to about 7 GeV for 3 nm.

An analytic calculation of the energy fluence spectrum of a linear accelerator

Abstract: Calculation of photon dose by convolution methods requires a knowledge of the fluence spectrum of photons produced by the linear accelerator treatment head But this spectrum is very difficult to measure accurately, and is often derived by Monte Carlo calculations modeling the elements of the treatment head In this paper an analytic calculation technique and the corresponding computer tool for calculating the photon energy fluence spectral distribution at any point in a bremsstrahlung field are presented Primary bremsstrahlung photon distributions are computed by modeling electron dispersion in layers in a thick target and using the thin target bremsstrahlung cross section formulas of Schiff The first Compton scatter from all materials in a linear accelerator treatment head is computed analytically Higher-order Compton scatter events and pair production annihilation photons are ignored, but the attenuation of both primary and first scattered photon fluence is computed Predictions of the computer implementation of the model are compared to measurements of bremsstrahlung production in a thick target and to Monte Carlo calculations of the energy fluence emerging from a linear accelerator Finally, the computer tool is used to investigate the source of collimator-dependent fluence fluctuations in air In agreement with other measurements, the principal contribution to fluence outside the geometric field is found to be from scatter in the flattening filter

Demonstration of ultraviolet lasing with a low energy electron beam

Abstract: We report on the design details of the first ultraviolet (UV) free-electron laser (FEL) oscillator driven by low-energy electrons from a radio-frequency linear accelerator. In our experiment we used a high-current, high brightness electron beam in combination with a wiggler of novel design to produce an FEL that lased at wavelengths from 369 to 380 nm using 45.9–45.2 MeV electrons. In addition we performed a proof-of-principle experiment that demonstrated the first ever photolithography on a photoresist-coated silicon wafer using an FEL light source.

Relativistic klystron two-beam accelerator

Abstract: Relativistic klystrons (RK's) are being developed as an RF power source for high gradient accelerator applications which include large linear electron-positron colliders, compact accelerators, and FEL sources. In a relativistic klystron two-beam accelerator (RK-TBA), the drive beam passes through a large number of RF output structures. High conversion efficiency of electron beam energy to RF energy is achieved in this concept by reacceleration of the modulated drive beam between output structures. We have conducted experiments studying the RF power extracted from various RK structures driven by modulated induction accelerator current pulses; our studies include work on improving the transport dynamics of the drive beam. We have started a demonstration in which the modulated induction beam current is reaccelerated by passage through subsequent induction accelerator cells. >

Radio frequency focused drift tube linear accelerator

Abstract: A drift tube linac incorporates rf-electric quadrupole focusing by employing drift tubes with only one drift-tube stem per particle wavelength and in which the lowest frequency RF cavity mode has a transverse magnetic field (TM010 -mode). Each drift tube comprises two separate electrodes that form a capacitor that couples to the axial electric field of the primary cavity mode. The electrodes operate at different electrical potentials, as determined by the RF fields in the cavity, and are supported by a single stem along the axis of a cylindrical cavity. Each electrode supports two fingers pointing towards the opposite end of the drift tube, forming a four fingered geometry that produces an RF quadrupole field distribution along its axis. The fundamental periodicity of the structure is equal to the particle wavelength (βλ) where β is the particle velocity in units of the velocity of light and λ is the free space wavelength of the rf. The particles traverse two distinct regions, namely the gaps between drift tubes, where the acceleration takes place, and the regions inside the drift tubes, where the RF focusing takes place. The linac of the present invention transforms the reverse fields into transverse fields for focusing such that the beam is not decelerated.

Vacuum arc ion source for the ITEP RFQ accelerator

Abstract: A version of vacuum arc ion source has been developed and constructed at the Institute for Theoretical and Experimental Physics, Moscow, for use with a heavy ion radio frequency quadrupole linac. The source is operated in a pulsed mode with a pulse length from 5 to 120 μs and a repetition rate of from 1/8 to 1 pps. The injection voltage is up to 90 kV depending on the kind of ions being used, and the beam current at the injector output is up to 500 mA. The results described in this article were made at a beam current of from 10 to 100 mA. In order to obtain ions having a charge‐to‐mass ratio of about 1/60, metals such as Cu, Mo, Ta, W, and Pb were used as the cathode material. Volt‐ampere characteristics and charge state distributions were measured. The charge state spectral variation was investigated throughout the arc current pulse duration as well as the dependence of the mean charge state of the beam ions on the melting point of the cathode material.

Heavy‐ion sources for radiation therapy

Abstract: The usefulness of particle beams for radiation therapy has been well and widely recognized. For the cure of cancer patients, many accelerator facilities have already been utilized, and some new facilities are now being put into operation, or are under construction. Considering the medical and biological requirements, light heavy ions with an energy of several hundred MeV/nucleon are regarded as being the most suitable species. A reasonable choice to this end is an accelerator complex, for an example, one comprising an ion source, an injector linac, and a synchrotron. The ion source is of great importance, since its characteristics strongly affect the overall performance of the accelerator system. A pulsed Penning source (PIGIS) has been successfully used at Lawrence Berkeley Laboratory. Recently, at the National Institute of Radiological Sciences a low‐duty pulsed PIGIS for the heavy‐ion medical accelerator in Chiba (HIMAC) has been developed; it has both a long lifetime and a high peak intensity. As other types of ion sources, an electron‐beam ion source (EBIS) and an electron‐cyclotron‐resonance ion source (ECRIS) are being developed at several laboratories. An EBIS is basically a pulsed source, and is being successfully used at Saclay. By using an after‐glow mode, two ECRISs have made remarkable progress at Grenoble and the Grand Accelerateur National d’Ions Lourds; similar tests are proceeding for the Schwer‐Ionen Synchrotron at the Gesellschaft fur Schwer‐Ionenforschung, the booster at Centre d’Europeen de Recherche Nucleaire, and the HIMAC. These different types of heavy‐ion sources are discussed from the viewpoint of their application to radiation therapy.

Fine tuning of linear accelerator accessories for stereotactic radiotherapy.

Abstract: Purpose : Experience with the University of Wisconsin's stereotactic radiotherapy (SRT) accessory system was applied to build a new system, facilitate alignment of linac photon beams with a Brown-Roberts-Wells (BRW) stereotaxy, and increase the versatility and stability of the stereotaxy. Methods and Materials : High tensile strength stainless steel was used in the floor stand to increase the range of gantry rotation relative to ranges allowed by truss-mounted stands. The collimator assembly and floor stand were each fitted with two-axis gimbal and translation adjustments in addition to the floor stand's three-axis adjustments. The head ring positioning assembly was fitted with two braces to prevent the head ring from deforming with patient motion. Six MV linac photon beam characteristics were measured with a computer-controlled scanning system and a diode in water, at source to surface distances (SSD) of 80 and 100 cm, and for 13 divergent collimators ranging in diameter from 1–4 cm at 100 cm SSD. Quality assurance software was applied to screen data for questionable consistency or symmetry. Integrity of the stereotaxy was evaluated with target simulation films and repeated measurements which were part of the quality assurance of clinical treatments. A method was developed using a glass etched contact reticle to obtain average simulated target to beam center distances (δav) from target simulation films. Results and Conclusion : New aspects of the current system have improved the ability to fine tune and analyze stereotactic alignment. Beam characteristics met stringent output criteria and penumbral widths were the same or narrower than penumbral widths reported elsewhere. The precision of measuring δav was 0.1 mm, and δav averaged over 50 target simulation films was 0.7 ± 0.1 mm. Results suggest that it may be useful to determine δav from target simulation films with the method described here.

Performance of the high brightness linac for the advanced free-electron laser initiative at Los Alamos

Abstract: The AFEL accelerator has produced beams of 1 nC with peak currents greater than 100 A and a normalized, rms emittance less than 2π mm mrad. The 1300 MHz standing-wave accelerator uses on-axis coupling cells. The electron source is a photoinjector with a CsK 2 Sb photocathode. The photoinjector is an integral part of a single 11-cell accelerator structure. The accelerator operates between 12 and 18 MeV. The beam emittance growth in the accelerator is minimized by using a photoinjector, a focusing solenoid to correct the emittance growth due to space charge, and a special design of the coupling slots between accelerator cavities to minimize quadrupole effects. This paper describes the experimental results and compares those results with PARMELA simulation. The simulation code PARMELA was modified for this effort. This modified version uses SUPERFISH files for the accelerator cavity fields, MAFIA files for the fields due to the coupling slots in the accelerator cells, and POISSON files for the solenoid field in the gun region.

Radio-Frequency Pulse Compression for Linear Accelerators.

Abstract: Recent efforts to develop plans for an electron-positron linear collider with center-of-mass energy approaching a TeV have highlighted the need for sources capable of delivering hundreds of megawatts of peak rf drive power at X-band frequencies. This need has driven work in the area of rf pulse compression, which enhances the peak power available from pulsed rf tubes by compressing their output pulses in time, accumulating the available energy into shorter pulses. The classic means of rf pulse compression for linear accelerators is SLED. This technique is described, and the problem it presents for multibunch acceleration explained. Other pulse compression schemes, capable of producing suitable output pulses are explored, both theoretically and experimentally, in particular Binary Pulse Compression and SLED-II. The merits of each are considered ,vith regard to gain, efficiency, complexity, size and cost. The development of some novel system components, along with the theory behind their design, is also discussed. The need to minimize copper losses in long waveguide runs led to the use of the circular $T E_{01}$ propagation mode in over-moded guide, requiring much attention to mechanisms of coupling power between modes. The construction and commissioning of complete, high-power pulse compression systems is reported on, as well as their use in the testing of X-band accelerating structures, which, along with the X-band klystrons used, were developed at SLAC in parallel with the pulse compression work. The focus of the dissertation is on SLED-II, the favored scheme in some current linear accelerator designs. In addition to our experimental results, practical implementation considerations and design improvements are presented. The work to date has led to detailed plans for SLED-II systems to be used in the Next Linear Collider Test Accelerator, now under construction at SLAC. The prototype of the upgraded system is near completion. Descriptions of various rf pulse-compression techniques besides the aforementioned three, including those pursued at institutions other than SLAC, are included to give a broad taste for the field and a sense of future possibilities.

Characterization of electron beams generated in a high‐voltage pulse‐line‐driven pseudospark discharge

Abstract: Emittance and energy measurements have been performed on a high‐brightness electron beam (≳1010 A/m2 rad2) with diameter in the range 1–3 mm and energy in the range 150–170 keV. This electron beam is generated by the mating of a hollow‐cathode discharge device operating in the pseudospark regime to the output of a high‐power pulse line accelerator. The measured effective emittance lies in the range between 30 and 90 mm mrad and increases with axial distance. Electron energy measurements indicate that the high‐energy electrons are generated during the first 20–30 ns of the discharge. Both the emittance and energy experiments were performed at two different ambient argon gas pressures (92 and 152 mtorr). Beam expansion as a function of axial position has also been studied and a lower bound on the beam brightness has been obtained.

Electron radiation dose tailoring by variable beam pulse generation

Abstract: A method and apparatus for controlling the delivered dose across a target area from an electron beam produced by a high energy, high power pulsed rf linear accelerator. Pulse width modulation as a function of scan position is applied to the rf drive pulses of the accelerator operated in a long pulse mode and fast feedback control is used to maintain uniform rf field intensity on an intra-pulse basis. In an alternative embodiment, rf drive pulses are inhibited as a function of scan position.

A simple magnetic spectrometer for radiotherapy electron beams.

Abstract: A small, lightweight, single-focusing magnetic spectrometer was designed, assembled, and tested for analysis of electron beams from radiotherapy electron linacs. The objective was to develop a low cost, simple device that could be easily replicated in other medical centers, and to demonstrate the practicality of individual electron counting for precise analysis of electron spectra. Two methods of spectroscopy have been developed. One method consists of counting electrons individually as a function of magnetic field setting. Electrons are deflected through 90 degrees in the magnetic spectrometer, through an exit slit, and into a scintillation detector. A second method consists of recording the complete spectrum of electron energies from the accelerator on a strip of film at a single magnetic field setting. A critical design element is the 10-cm long collimator for electrons entering the magnet gap, with defining apertures and scraper slits. The spectrometer's cleanliness of transmission, energy calibration, and resolution were all tested at 10 and 16 MeV using the nearly monoenergetic electron beam of the accelerator at the National Research Council of Canada (NRCC). These accelerator tests, and also Monte Carlo trajectory simulations, both show that contamination of the transmitted spectrum due to scattered or knock-on electrons is negligible. Low-energy characteristics were tested using a 90Sr + 90Y beta-particle source. The energy calibration of the 90 degree spectrometer mode was based on mapping the magnetic field and also electron trajectory computer simulations. That calibration agrees with the NRCC's own calibrated scale to 0.8% for the single-particle counting method and to 1.3% for the film method. The energy resolution was measured to be 2% at 10 MeV, which is adequate for radiotherapy linac measurements. The acceptance half angle is 0.5 degrees or less, depending on the aperture size, which is adequate for electron angular distribution measurements within the forward cone of the electron beam. Used with film, the spectrometer is a simple, accurate, and highly transportable device for measuring radiotherapy electron energy spectra.

Effects of proton beam quality on the production of gamma rays for nuclear resonance absorption in nitrogen

Abstract: We describe a method for performing nuclear resonance absorption with the proton beam from a radio frequency quadrupole (RFQ) linear accelerator. The objective was to assess the suitability of the pulsed beam from an RFQ to image nitrogen relative to that of electrostatic accelerators. This choice of accelerator results in tradeoffs in performance and complexity, in return for the prospect of higher average current. In spite of a reduced resonance attenuation coefficient in nitrogen, we successfully produced 3D tomographic images of real explosives in luggage the first time the unoptimized system was operated. The results and assessments of our initial laboratory measurements are reported.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Total-body irradiation on an isocentric linear accelerator: a radiation output compensation technique

Abstract: A treatment technique for total-body irradiation (TBI) is proposed that combines are therapy with dynamic output control to achieve high-grade dose uniformity. The patient lies on a low couch and receives exposure in the prone and supine positions from a modulated arcing beam. The technique has been validated using a personal computer to control the linear accelerator and the authors demonstrate that only minor alterations to current dynamic therapy systems would be required. They have examined the practical application of this treatment with emphasis on methods of conformal therapy where an optimized dose distribution is prepared from a matrix of caliper measurements taken from the patient. This technique provides a means for regular TBI treatment on a computer-controlled linear accelerator that is easy to set up, requires short exposure times and is comfortable for the patient.

Performance of the Superconducting Super Collider H−rf volume ion source and Linac injector

Abstract: The Superconducting Super Collider (SSC) ion source is required to provide a 30 mA H− beam at 35 keV with a normalized rms emittance (en‐rms) of less than 0.18 π mm mrad. An rf‐driven volume source was chosen for the commissioning of the SSC linear accelerator (Linac). The divergent ion source output beam is matched into the radio frequency quadrupole accelerator (RFQ) by an electrostatic low‐energy beam transport (LEBT). The SSC Linac injector (consisting of ion source, LEBT, and RFQ) is required to provide 25 mA of H− beam (pulse width of 9.6–35 μs at 10 Hz repetition rate) at 2.5 MeV with transverse normalized rms emittance (et‐n‐rms) of less than 0.2 π mm mrad and longitudinal normalized rms emittance (el) of less than 0.82×10−6 eV s. The performance of our rf volume source and initial experimental results from the SSC injector are discussed.

Slac measurements of the neutron spin-structure function ?

Abstract: Results from a measurement of the neutron spin-dependent structure functiong1n(x) over a range inx from 0.03 to 0.6 and withQ2>1 (GeV/c)2 are presented. The experiment consisted of scattering a longitudinally polarized electron beam from the Stanford Linear Accelerator off a polarized3He target and detecting scattered electrons in two magnetic spectrometers. The results are interpreted in the quark-parton model and used to test the Bjorken sum rule.

Amplification of spontaneous emission with two high-brightness electron bunches of the ISIR linac

Abstract: Recently, self-amplified spontaneous emission (SASE) has been observed at wavelengths of 20 and 40 μm with high-brightness single-bunch electron beams of the 38 MeV L-band linear accelerator (linac) at The Institute of Scientific and Industrial Research in Osaka University. A study has been made to generate two electron bunches for amplifying the SASE with another electron bunch under an oscillator configuration at a wavelength of 40 μm. A grid pulser of the electron gun has been developed for generating two electron bunches at the interval corresponding to the round-trip time of an optical cavity. The total charge of the electrons and the energy spread of the beam accelerated at an energy of 17.1 MeV are 40 nC and 2% (FWHM), respectively. After further optimization of the conditions of the microwave supplied to each component of the accelerator system, experiments of two-bunch amplification will be performed.

Design and construction of heavy ion RFQ linac with effective acceleration structure

Abstract: At the Tokyo Institute of Technology, generating a plasma with a heavy ion beam has been studied for basic research on inertial fusion and a heavy-ion pumped laser. These experiments require a high intensity and high brightness beam. An 80 MHz heavy-ion RFQ linac is being constructed to meet the requirements. This linac accelerates particles with a charge to mass ratio ( q A ) greater than 1 16 from 5 keV/amu up to 214 keV/amu. Two-dimensional (2D) machining is applied for cutting of the RFQ vane-tips. We simulated the beam optics including effects of higher order harmonies in the intervane potential (H. Deitinghoff, A. Schempp, H. Klein and O. Pan, Particle Acc. 37–38 (1992) 47; Chen Chia-Erh, Fang Jia-Xun, Li Weigo, Pan Oujia, Lu Yuanrong, Li Deshan, Wang Lishan, Yu Maolin, H. Deitinghoff, A. Schempp and H. Klein, Proc. European Particle Acc. Conf. (1992) p. 1328) for optimization of the vane parameters. In order to increase the acceleration efficiency, synchronous phase was gradually raised from −30° to −20° in the accelerator section of the cavity. The expected beam transmission is 91.8% for a beam current of 0 mA and 68.4% for 10 mA.

An accelerator/wiggler for high efficiency FEL operation

Abstract: A possible approach to high efficiency FEL operation is to combine a microwave linear accelerator and magnetic wiggler into a single structure. As the electrons lose energy to the radiation at the FEL oscillation wavelength (e.g. 10 μm), energy is replaced by the microwave linac. The electron beam acts as a catalyst for the conversion of microwave power to infrared power. Several advantages to the accelerator/wiggler are: it is possible to obtain high conversion efficiency in a short length; small-signal gain reduction can be avoided; power extraction may be increased by increasing length; there is little detrapping; and electron beam energy out of the wiggler is relatively monochromatic, permitting efficient energy recovery. A six period, full scale model of the accelerator/wiggler has been fabricated to check the computer simulations for both microwave and magnetic properties. Microwave measurements on this model indicate that the predicted Q is accurate, that there is an approximate 1.5% error in the predicted resonant frequency and that critical coupling to the structure in the presence of the electron beam can be achieved with a direct, rectangular waveguide feed.

Design of a New Type of Variable-Frequency Radio-Frequency Quadrupole Linac with a Folded-Coaxial Resonator

Abstract: A new type of variable-frequency radio-frequency quadrupole (RFQ) linac that will be constructed as a new injector for the RIKEN heavy-ion linac (RILAC) is proposed. It is designed to accelerate ions with mass-to-charge ratios of 7 to 28 at up to 450 keV per charge by varying its operational frequency from 17 to 35 MHz. The resonator has a folded-coaxial structure, and the resonant frequency is changed by a movable shorting plate. As a result of a low-power test on a half-scale model, the required rf power is found to be 6 kW at 17 MHz, and it increases to 34 kW at 35 MHz in cw operation.

Design of a current-independent matching section for APDF

Abstract: We describe the design of a current-independent matching section which could be used to match a 100-MeV, CW beam from a 7-MeV, 350-Mhz RFQ into a 350-Mhz DTL for the proposed Accelerator Performance Demonstration Facility (APDF). This facility is being proposed to demonstrate the performance of a high-current, CW front-end (up to 40-MeV and including a funnel) which would be applicable for the accelerator production of tritium, accelerator transmutation of waste, and accelerator-based conversion of defense waste programs. A detailed description of the APDF is given in another paper presented at this conference.