The China Spallation Neutron Source (CSNS) is a major facility for neutron science in China, and is currently operating at an averaged beam power of 170 kW with a beam energy of 1.6 GeV and repetation rate of 25 Hz. In 2024, the CSNS Upgrade project (CSNS-II) was launched aiming to improve the average beam power to 500 kW. In the sequence, a number of new instrumentations will be equiped at the new superconducting linac, RCS and new beamlines. In this talk, we will present an overview of the new diagnostics and the corresponding the high-intensity challenges. We will also report the recent progresses on the RCS beam position monitors, the non-invasive profile monitors, e.g., the ionization profile monitor and laser-wire profile monitor, and the implementation of the novel large-diameter CNT-wire material.

CSNS-II superconducting Section Beam Loss Measurement Electronic Design The CSNS-II linear accelerator upgrade will adopt superconducting accelerator structures, with the beamline enclosed in low-temperature modules. Detection of beam loss can only be done on the outer surface of the low-temperature modules. The CSNS-II accelerator plans to use a parallel plate multi-electrode ionization chamber as the beam loss monitor (BLM) probe for the superconducting section. The electronic system of the beam loss measurement (BLM) is primarily used for signal conditioning, digitization (ADC), transmission storage as EPICS PV quantities, and providing interlock signals for machine protection based on the output signals from the BLM probes. The main tasks of the development of the beam loss measurement (BLM) electronic system include: signal conditioning of weak current output from the BLM probes in the analog circuit section; and analog-to-digital conversion, digital signal processing, storage, PV quantity publication in the digital circuit section for the front-end analog output signals.

Target Multi-Wire Scanner is a beam diagnostics device in the CSNS-II accelerator, designed to measure the pre-target beam profile. This paper details the hardware composition, software architecture, and beam-target interaction test results of the CSNS-II front-end multi-wire scanner readout system. In contrast to the CSNS predecessor, the upgraded system employs a hybrid software architecture combining a LabVIEW-based signal acquisition platform with a standardized EPICS Input/Output Controller (IOC) developed in C. The LabVIEW software handles signal acquisition and front-end electronics control, while processed data is transmitted to the EPICS IOC for standardized data publishing. This architecture enhances system stability and ensures reliable EPICS-based data interaction, demonstrating an optimized instrumentation framework for high-precision beam diagnostics in high-power proton accelerators.

In the China Spallation Neutron Source II (CSNS-II), the H⁻ beam will be accelerated in the Linac to 300 MeV. Subsequently, the electrons are stripped from the H⁻ ions through a stripping foil during injection into the Accumulator Ring, converting them into a proton beam. Wire scanners are employed to measure the transverse beam profile and emittance in the injection area. This paper presents thermal analysis of the wire scanners in the Linac. To meet measurement requirements, the beam pulse length will be 575 μs, and the current will be approximately 30 mA. Given these parameters, carbon nanotube (CNT) or tungsten wires are considered as potential materials for measuring beam profiles throughout the facility. However, when the beam pulse length exceeds 200 μs, the temperature of a 33 μm tungsten wire surpasses its sublimation threshold (3000 K), approaching its melting temperature. This analysis compares the temperature of different wire materials. The results indicate that under the specified beam parameters, CNT wires exhibit a significantly lower temperature increase, making it the optimal choice.