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We propose a new scheme of producing an intense neutron beam whose yields may exceed those of the existing facilities by a few to several orders of magnitude in the sub-eV region. This scheme employs a MeV gamma beam extracted from circulating quantum ions, which has been recently proposed. The gamma beam is directed to a deuteron target and the photo-disintegration process generates a neutron beam. The calculated neutron energy spectrum is nearly flat down to the neV range, and thus there exists a possibility to utilize a good quality of neutrons especially in sub-eV energy region without using a moderator.

A compact accelerator-driven neutron source (CANS) has been proposed and designed by the Peking University (PKU) RFQ group. The source is based on a compact deuteron RF accelerator that delivers an average current of a few mA of deuterons at 11MeV to the target. The accelerator consists of a short radio frequency quadrupole (RFQ) followed by efficient interdigital H-mode drift tube linac (IH-DTL) structure. The total length of the whole accelerator structure is 4.96m, including 1.76m for the 4-vane RFQ and 2.70m for the IH-DTL. The dynamic simulation results show that the beam has excellent quality, with transmission efficiency higher than 99%. The transverse and longitudinal normalized rms emittance at the DTL exit is 0.29mm⋅mrad and 0.12 MeV⋅deg, respectively. Details of the beam dynamics of the RFQ and IH-DTL are presented in this paper.

The developed spherical plasma focus model is used in this study to investigate the optimum neutron yield in terms of the gas pressure, cathode radius and external inductance. The optimum values for these parameters are found separately. Then, the charging voltage is varied from 25kV to 35kV with 1kV increment by using these separately found optimum values to see the rate of increase in neutron yield. While the used gas pressure range is 1–40Torr with 1Torr increment, cathode radius range is 11.5–17cm with 0.5cm increment. External inductance is varied from 10nH to 150nH with 5nH increment. The optimum values for gas pressure, cathode radius and external inductance are found to be 26Torr, 15cm and 75nH, respectively. Even though combining these separately found optimum values of pressure, cathode radius and external inductance does not necessarily form an optimized set of operational conditions for the SPF, they lead to a higher neutron yield in that while neutron yield with these separately found optimum values at 25kV charging voltage is $2.82\times 10^{13}$ (higher than the measured neutron yield of $1.26\times 10^{13}$ at 25kV), it increases to $1.32\times 10^{14}$, when charging voltage is increased to 35kV. Using these values shows that spherical plasma focus device can be used as a neutron source with high neutron yield (on the order of $10^{14}$).

Spallation neutron sources are the primary accelerator-driven source of intense neutrons. They require high power proton accelerators in the GeV energy range coupled to heavy metal targets for efficient neutron production. They form the basis of large scale neutron scattering facilities, and are essential elements in accelerator-driven subcritical reactors. Demanding technology has been developed which is enabling the next generation of spallation neutron sources to reach even higher neutron fluxes. This technology sets the stage for future deployment in accelerator-driven systems and neutron sources for nuclear material irradiation.

The output and target lifetime of a conventional electrostatic neutron generator are limited by the voltage stand-off capability and the acceleration of molecular species from the ion source. As an alternative, we suggest that the deuterium beam achievable from a compact high intensity ECR source can be injected directly into a compact RFQ to produce a more efficient compact neutron production system. Only the d⁺ ions are accelerated by the RFQ, which can also produce much higher output energies than electrostatic systems, resulting in a higher neutron output with a longer target lifetime. The direct injection of the beam makes the system more compact than the multielement, electrostatic systems typically used for extraction of the beam and subsequent transport and matching into the RFQ. We have designed and optimized a combined extraction/matching system for a compact high current deuterium ECR ion source injected into a high frequency RFQ structure, allowing a beam of about 12 mA of d⁺ ions to be injected at a modest ion source voltage of 25 kV. The end wall of the RFQ resonator serves as the ground electrode for the ion source, resembling DPI (direct plasma injection). For this design, we used the features of the code IGUN to take into account the electrostatic field between the ion source and the RFQ end wall, the stray magnetic field of the ECR source, the defocusing space charge of the low energy deuteron beam, and the rf focusing in the fringe field between the RFQ vanes and the RFQ flange.

A fast neutron (E> MeV) irradiation facility is under development at the 70 MeV SPES proton cyclotron at LNL (Legnaro, Italy) to investigate neutron-induced Single Event Effects (SEE) in microelectronic devices and systems. After an overview on neutron-induced SEE in electronics, we report on the progress in the design of ANEM (Atmospheric Neutron EMulator), a water-cooled rotating target made of Be and W to produce neutrons with an energy spectrum similar to that of neutrons produced by cosmic rays at sea-level. In ANEM, the protons from the cyclotron alternatively impinge on two circular sectors of Be and W of different areas; the effective neutron spectrum is a weighted combination of the spectra from the two sectors. In this contribution, we present the results of thermal-mechanical Finite Element Analysis (ANSYS) calculations of the performance of the ANEM prototype. The calculations at this stage indicate that ANEM can deliver fast neutrons with an atmospheric-like energy spectrum and with an integral flux ${\mathrm{\Phi }}_n$(1-70 MeV) $\sim$10⁷ n cm${}^{-2}$s${}^{-1}$ that is 3×10⁹ more intense than the natural one at sea-level: a very competitive flux for SEE testing.

This chapter describes the development of boron neutron capture therapy (BNCT) from several technical aspects, including the neutron source, dosimetry and the treatment process. The principle of BNCT to kill tumor cells is mainly based on the nuclear reaction between thermal neutrons and boron. The energy generated by this nuclear reaction will destroy the double helix structure of DNA in the nucleus, making it impossible to repair and causing apoptosis of the whole cell. While the boron drug is the protagonist, the development and application of neutron sources and nuclear-related technologies are also a crucial aspect. The differences between the two types of neutron source, reactor-based and accelerator-based, as well as the key components and related technologies of these neutron sources are discussed. Three typical BNCT facilities in the world are also introduced. An entire section is dedicated to dosimetry, as accurate dose assessment and calculation are the key to the success of BNCT. The chapter is completed by a step-by-step explanation of the treatment planning system and treatment process.

Spallation neutron sources are the primary accelerator-driven source of intense neutrons. They require high power proton accelerators in the GeV energy range coupled to heavy metal targets for efficient neutron production. They form the basis of large scale neutron scattering facilities, and are essential elements in accelerator-driven subcritical reactors. Demanding technology has been developed which is enabling the next generation of spallation neutron sources to reach even higher neutron fluxes. This technology sets the stage for future deployment in accelerator-driven systems and neutron sources for nuclear material irradiation.

This paper describes the scientific aims and potentials as well as the preliminary technical design of IRIDE, an innovative tool for multi-disciplinary investigations in a wide field of scientific, technological and industrial applications. IRIDE will be a high intensity “particles factory”, based on a combination of high duty cycle radio-frequency superconducting electron linacs and of high energy lasers. Conceived to provide unique research possibilities for particle physics, for condensed matter physics, chemistry and material science, for structural biology and industrial applications, IRIDE will open completely new research possibilities and advance our knowledge in many branches of science and technology. IRIDE is also supposed to be realized in subsequent stages of development depending on the assigned priorities.