A prototype Canadian compact accelerator-driven neutron source (PC-CANS) is proposed. The source will utilize a high-intensity compact proton RF linear accelerator, delivering a peak current of 20 mA with a 5% duty factor of protons at 10 MeV to the target. The accelerator comprises a short radio-frequency quadrupole (RFQ) to 3 MeV, followed by a drift tube Linac (DTL) structure accelerating to 10 MeV. Various room temperature DTL variants, including Alvarez, and H-mode variants using APF, KONUS, and NPS (negative synchronous phase) beam dynamics are considered at a frequency of 352.2MHz. This paper compares the beam dynamics of the various structures. Comparisons include beam transmission, longitudinal and transverse emittance growth, Linac length, RF power and longitudinal and transverse phase acceptance. Beam dynamics simulations were conducted using the PARMTEQ, LANA, PARMILA, and Trace-3D codes. This work contributes to the development of high power proton linacs by providing a comparison in performance over several Linac structures.

We present, in this paper, the design result of the beam dynamics for a heavy-ion injection line of the Xi’an 200 MeV Proton Application Facility (XiPAF) upgrading project. The heavy-ion injection line consists of an electron cyclotron resonance (ECR) ion source (IS) system, a low energy beam transport line (LEBT), a four-vane radio frequency quadrupole (RFQ) accelerator, an interdigital H-mode drift tube linac (IH-DTL) with an electromagnetic quadrupole (EMQ) structure, and a linac-to-ring beam transport line (LRBT). The injection line can provide 2 MeV/u heavy-ion beams which will be injected into the synchrotron via multi-turn injection through an electrostatic septum. The characteristics of the injected beam are validated using the TraceWin code to ensure they meet the specifications for transverse emittance, momentum spread, mismatch factor of Twiss parameters, and beam dispersion.

The tuning and stabilization of long normal conducting radiofrequency cavities present specific challenges that are critical for the reliable operation of linear accelerators. When the cavity length exceeds the RF wavelength several times, small mechanical deformations, misallignement and thermal gradients can lead to significant detuning, acceleting field distortion and excitation of unwanted modes. These effects are particularly relevant for structures such as Drift Tube Linacs and Radio Frequency Quadrupoles, which operate in the low-energy sections of linacs, where compliance of the design accelerating field profile and frequency stability are essential for efficient beam transport and acceleration: this requires careful stabilization strategies. In this contribution the experience with the DTL of the ESS linac, as well as from RFQs developed in the Anthem and SPES projects, will be presented.

The European Spallation Source (ESS) has recently completed beam commissioning up to the tuning beam dump, reaching a proton energy of 800 MeV. This talk will focus on the technical commissioning of the linear accelerator, covering both the normal-conducting and superconducting sections, as well as the testing and integration of superconducting cryomodules. We will describe the phased commissioning process, including high-power RF conditioning of the normal-conducting cavities, superconducting RF (SRF) cavities, and power couplers. Highlights from cryomodule installation, cooldown, and performance testing will be presented. The talk will also discuss integration challenges, cross-functional coordination, and key lessons learned during this phase. Selected results will demonstrate the system’s readiness for high-power beam operation and outline the next steps in ESS commissioning.

The China Spallation Neutron Source (CSNS) accelerator complex comprises an 80 MeV H⁻ normal-conducting linear accelerator (linac), a 1.6 GeV rapid cycling synchrotron (RCS), and associated beam transport lines. Following multiple rounds of beam commissioning, the beam power delivered to the target has been successfully increased to 170 kW, surpassing the design value by 70%. Building on this achievement, the power upgrade project (CSNS-II) was launched in 2024, aiming to elevate the beam power to 500 kW. This upgrade presents significant challenges for the linac, requiring a fourfold increase in beam current and a fortyfold increase in beam power. To address these challenges, extensive beam studies have been conducted at the linac. These studies focus on optimizing the lattice and beam matching, precisely measuring beam parameters, refining the computer model, investigating beam loss mechanisms, and implementing strategies to minimize beam loss. These efforts are critical to ensuring the successful realization of the CSNS-II power upgrade.

The China Spallation Neutron Source (CSNS) is a large multidisciplinary experimental facility that generates neutrons by targeting a strong current proton accelerator. Its linear accelerator consists of a front-end accelerator, a 3 MeV RFQ accelerator, and an 80 MeV DTL accelerator. The second phase of the project will upgrade the linear accelerator by installing superconducting cavities after the DTL exit, increasing the beam energy to 300 MeV. This paper will present a simulation study that examines the effects of different magnets and cavity failures in the linear accelerator on beam quality, including emittance growth and beam loss.

In accelerator-based spallation neutron sources, which include a rapid cycling synchrotron (RCS), the energy spread at the end of the linac is a crucial parameter that significantly impacts the operational efficiency of the downstream RCS ring. However, in recent years, the energy spread at the linac of the Chinese Spallation Neutron Source has been inadequately measured due to limited methods for longitudinal phase space measurement. This paper presents a study on measuring the energy spread using wall current monitors at the linac. The results indicate that the energy spread is at the 10⁻³ level, consistent with simulations. Nevertheless, the uncertainty remains relatively high, necessitating further efforts to improve measurement accuracy in the future.