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The ANTHEM (Advanced Technologies for Human-centered Medicine) Radio-Frequency Quadrupole (RFQ) will employ eight coaxial power couplers, which will be magnetically coupled to the device through a loop antenna. The coupler design can support up to 140 kW in continuous wave operation. This paper presents the design of the cavity used for high-power testing, with the primary objectives of both optimizing the coupling between the couplers and ensuring operations at the designated operating frequency. Furthermore, the paper encompasses thermal and structural assessments conducted through numerical simulations. [ABSTRACT FROM AUTHOR]

Accelerator Mass Spectrometry (AMS) of isotopes with abundant negative ion-forming isobars often requires the use of large accelerators to achieve high sensitivity measurements. The Isobar Separator for Anions (ISA) is a radio frequency quadrupole (RFQ) reaction cell system that can provide selective isobar suppression in the low energy system, prior to injection into an accelerator. A commercial version from Isobarex Corp. has been installed in a second injection line of the 3 MV tandem accelerator system at the A. E. Lalonde AMS Laboratory, University of Ottawa. Here, we present the characterization of the ISA for its optimization of S– suppression and Cl– transmission. He gas was selected as a cooling buffer gas, as it provided the best Cl– transmission of ∼50 % through the ISA column. These tests use NO 2 as a reaction gas due to its well-known exothermic reaction with S– but endothermic reaction with Cl–. More than six orders of magnitude reduction of S to Cl has been observed. [ABSTRACT FROM AUTHOR]

The article describes the results of a study of the effect of a supersonic gas jet on the formation and extraction of deuterium-substituted ions from a liquid supplied through a capillary into a radio-frequency quadrupole coupled to a time-of-flight mass spectrometer with orthogonal ion injection. The supersonic gas jet is formed inside a cylindrical channel and passes through an electron ionization ion source. With an increase in the flow rate of the a solution, there was no steady trend in the relative contributions of deuterated ions from the liquid phase. The results confirm the prospects of using a supersonic jet to create a high-performance source of deuterium-substituted ions from a liquid supplied into a vacuum region under residual pressure of 10–4 Torr without using strong electric fields. [ABSTRACT FROM AUTHOR]

The article describes the results of a study of the effect of a supersonic gas jet on the formation and extraction of deuterium-substituted ions from a liquid supplied through a capillary into a radio-frequency quadrupole coupled to a time-of-flight mass spectrometer with orthogonal ion injection. The supersonic gas jet is formed inside a cylindrical channel and passes through an electron ionization ion source. With an increase in the flow rate of the a solution, there was no steady trend in the relative contributions of deuterated ions from the liquid phase. The results confirm the prospects of using a supersonic jet to create a high-performance source of deuterium-substituted ions from a liquid supplied into a vacuum region under residual pressure of 10–4 Torr without using strong electric fields. [ABSTRACT FROM AUTHOR]

The aim of this work was the assessment of the ability of a supersonic jet to accumulate sufficiently dense ion clouds inside the quadrupole, the ion cloud being “heated” to a relatively high temperature under a relatively low density of the residual gas (pressure lower than 10–4 Torr). Kinetic measurements gave an estimate of the number of accumulated ions at the beginning of the quadrupole of about 2 × 107 and their internal temperature of 6000 K. [ABSTRACT FROM AUTHOR]

Abstract: A new way to form the supersonic gas flow for producing and transportation the ions under study without their significant loss into a mass analyzer is described. The main objective of the paper is to show a relevancy of the approach. For both the argon–xenon gas mixture and atmospheric air fed as supersonic flow and in an effusion mode, the distributions of density for the recorded ions across their moving direction as well as other experimental dependencies were measured. The results of these measurements may be explained by formation of a supersonic gas flow with a divergence which is significantly smaller than the predicted one by “evident” model. The data analysis shows that only very small fraction of the ions formed inside the supersonic gas flow is recorded by the existing system. To eliminate these difficulties, it is suggested to turn the ions from the gas flow in the direction orthogonal to the initial one using two-grid electrostatic mirror before inserting the ions into the time-of-flight mass spectrometer with orthogonal injection of ions. The computer simulation has shown efficiency of such an approach. [Copyright &y& Elsevier]

Accelerator-driven systems (ADS) have evoked lot of interest the world over because of their capability to incinerate the MA (minor actinides) and LLFP (long-lived fission products) radiotoxic waste and their ability to utilize thorium as an alternative nuclear fuel. One of the main subsystems of ADS is a high energy (∼1 GeV) and high current (∼30 mA) CW proton Linac. The accelerator for ADS should have high efficiency and reliability and very low beam losses to allow hands-on maintenance. With these criteria, the beam dynamics simulations for a 1 GeV, 30 mA proton Linac has been done. The Linac consists of normal-conducting radio-frequency quadrupole (RFQ), drift tube linac (DTL) and coupled cavity drift tube Linac (CCDTL) structures that accelerate the beam to about 100 MeV followed by superconducting (SC) elliptical cavities, which accelerate the beam from 100 MeV to 1 GeV. The details of the design are presented in this paper. [ABSTRACT FROM AUTHOR]

A new type of resonance ionization laser ion source (RILIS) is presently being developed and tested at the off-line mass separator at Mainz University for future use at on-line exotic rare isotopes production facilities. For highest isobaric selectivity, this RILIS approach decouples the evaporation and ionization process. A further advantage is the generation of full temporal control of the resulting high quality ion beam. These facts are realized by a combination of atomizer – ion repeller – ion cooler and trap, which is operated together with a state-of-the-art, all solid state laser system. The principle and performance of this laser ion source trap (LIST) system are discussed applying simulation studies for the repeller-trap combination and first measurements for characterization. [ABSTRACT FROM AUTHOR]

The Penning trap mass spectrometer ISOLTRAP plays a leading role in mass spectrometry of short-lived nuclides. The recent installation of a radio-frequency quadrupole trap and a carbon cluster ion source allowed for the first time mass measurements on exotic nuclei with a relative uncertainty of δm/m≈1×10−8. The status of ISOLTRAP mass spectrometry and recent highlights are presented. [Copyright &y& Elsevier]

A new type of resonance ionization laser ion source, which shall combine the advantages of a laser ion source with those of an ion trap, is proposed. The primary purpose of such a laser ion source trap, which is based on a gas-filled linear radio-frequency quadrupole ion trap system, is the decoupling of evaporation and ionization processes. Furthermore optimum temporal control on the generated ion bunch is obtained. Both effects will lead to a significantly increased isobaric selectivity and ion beams of low emittance. A large variety of operational modes, ranging from quasi-dc to microseconds-bunched radioactive ion beams with variable pulse width and repetition rate, can be chosen freely and beam energies can easily be altered. The principles and the layout of LIST will be discussed on the basis of atom and ion trajectory simulations and resulting performance parameters. [Copyright &y& Elsevier]

The 750 MHz PIXE-RFQ (radio-frequency quadrupole), developed and built at CERN, provides 2 MeV protons over a length of one meter for proton-induced X-ray emission analysis (PIXE) of cultural heritage artwork. In this paper, we report low-power rf measurements and tuning of the PIXE-RFQ, which have been completed mid-2020. Using a novel algorithm based on direct measurements of the response matrix, field and frequency could be tuned at the same time in only two steps to satisfying accuracy. Additionally, we report measurements of single modules, quality factors, and coupling strength. In all cases, very good agreement between rf measurement and design values was observed. [ABSTRACT FROM AUTHOR]

This paper describes the physical design of a radio-frequency quadrupole (RFQ) accelerator for a compact accelerator-driven neutron source. The 325-MHz RFQ accelerates a 30-mA deuteron beam from 50 keV to 2 MeV, which is directly matched to the drift-tube linac (DTL) without a separate beam matching section. The objective of this design is to obtain a short RFQ with a tolerable transmission and power consumption. Using a modified four-section procedure, the inter-vane voltage is ramped with RFQ longitudinal position to obtain the required short length, and the focusing strength is varied to suppress beam loss. The RFQ has a length of 193.2 cm, with a peak power consumption of 186 kW, and a beam transmission of 94.1%. [ABSTRACT FROM AUTHOR]