Characterization of the upgraded photoinjector at the Chinese Academy of Engineering Physics Terahertz Free Electron Laser Facility.

The Chinese Academy of Engineering Physics Terahertz Free Electron Laser Facility (CAEP THz FEL, CTFEL) has been operated as a user facility for over five years. To further meet the growing demands of modern science, an upgrade project for an infrared-terahertz free electron laser facility based on CTFEL has been proposed to broaden the frequency range from 0.1-4.

Simulation analysis of 35 MeV high-power electron accelerator driven white neutron source target.

The white neutron source driven by an electron accelerator utilizes a pulsed electron beam to bombard a target, producing neutrons through photoneutron reactions. The white neutron source of photoneutron reaction has advantages such as compact structure, low cost, capability of generating ultra-short pulse, and wide applications in the resonance energy region, effectively complementing reactor neutron sources and spallation neutron sources. The development of high-current, high-power electron accelerator-driven white neutron sources is of significant importance for neutron science research and nuclear technology applications.

Bunch-by-bunch position measurement with sub-micron resolution at nanoseconds separation using wideband cavity beam position monitors.

We developed a wideband RF cavity beam position monitor (CBPM) with a 217 MHz bandwidth centered at the 4.875 GHz dipole mode frequency as part of the preliminary research for a high-repetition-rate hard x-ray free electron laser project at the Chinese Academy of Engineering Physics. This paper presents new results demonstrating bunch-by-bunch position measurements on electron bunches spaced by 2.

Effects of ultra-high dose rate radiotherapy with different fractions and dose rate on acute and chronic lung injury in mice.

Ultra-high dose rate radiotherapy (FLASH radiation) can naturally render normal tissues around the tumor tissue resistant to radiotherapy. In contrast, the tumor tissue remains sensitive to radiation under the same conditions. However, the effects of different fractions and dose rates on FLASH radiation remain unclear.

FLASH radiotherapy using high-energy X-rays: Current status of PARTER platform in FLASH research.

Purpose: Recent studies indicated that ultrahigh dose rate (FLASH) radiation can reduce damage to normal tissue while maintaining anti-tumour activity compared to conventional dose rate (CONV) radiation. This paper provides a comprehensive description of the current status of the Platform for Advanced Radiotherapy Research (PARTER), which serves as the first experimental FLASH platform utilizing megavoltage X-rays and has facilitated numerous experiments.

Methods And Materials: PARTER was established in 2019 based on a superconducting linac to support experimental FLASH studies using megavoltage X-rays.

A continuous ultra-narrow impulse synchronizer using a monolithic field programmable gate array for fast deployment and scalability.

Ultra-narrow pulses serve as critical components in numerous applications. These pulses have ultra-fast leading edges that typically function as precision trigger signals to synchronize various instruments. Ultra-narrow pulses inherently exhibit an ultra-wide bandwidth, gaining significant attention in diverse electronic systems encompassing communications, radar imaging, electronic warfare, and others.

Comparison of intratumor and local immune response between MV X-ray FLASH and conventional radiotherapies.

Background/purpose: Investigating the antitumor effect and intratumor as well as local immune response in breast cancer-bearing mice after MV X-ray ultra-high dose rate radiotherapy (FLASH-RT) and conventional dose rate radiotherapy (CONV-RT).

Materials/methods: Six-week-old female C57BL/6 mice were inoculated subcutaneously with Py8119 and Py230 breast tumor cells in the inguinal mammary gland and administered 10 Gy abdominal 6 MV X-ray FLASH-RT (125 Gy/s) or CONV-RT (0.2 Gy/s) 15 days after tumor inoculation.

FLASH X-ray spares intestinal crypts from pyroptosis initiated by cGAS-STING activation upon radioimmunotherapy.

DNA-damaging treatments such as radiotherapy (RT) have become promising to improve the efficacy of immune checkpoint inhibitors by enhancing tumor immunogenicity. However, accompanying treatment-related detrimental events in normal tissues have posed a major obstacle to radioimmunotherapy and present new challenges to the dose delivery mode of clinical RT. In the present study, ultrahigh dose rate FLASH X-ray irradiation was applied to counteract the intestinal toxicity in the radioimmunotherapy.

Radioprotective effect of X-ray abdominal FLASH irradiation: Adaptation to oxidative damage and inflammatory response may be benefiting factors.

Background: Ultrahigh dose-rate irradiation (FLASH-IR) was reported to be efficient in tumor control while reducing normal tissue radiotoxicity. However, the mechanism of such phenomenon is still unclear. Besides, the FLASH experiments using high energy X-ray, the most common modality in clinical radiotherapy, are rarely reported.

First demonstration of the FLASH effect with ultrahigh dose rate high-energy X-rays.

Purpose: This study aimed to evaluate whether high-energy X-rays (HEXs) of the PARTER (platform for advanced radiotherapy research) platform built on CTFEL (Chengdu THz Free Electron Laser facility) can produce ultrahigh dose rate (FLASH) X-rays and trigger the FLASH effect.

Materials And Methods: EBT3 radiochromic film and fast current transformer (FCT) devices were used to measure absolute dose and pulsed beam current of HEXs. Subcutaneous tumor-bearing mice and healthy mice were treated with sham, FLASH, and conventional dose rate radiotherapy (CONV), respectively to observe the tumor control efficiency and normal tissue damage.

High-energy high-dose microfocus X-ray computed tomography driven by high-average-current photo-injector.

High-energy, high-dose, microfocus X-ray computed tomography (HHM CT) is one of the most effective methods for high-resolution X-ray radiography inspection of high-density samples with fine structures. Minimizing the effective focal spot size of the X-ray source can significantly improve the spatial resolution and the quality of the sample images, which is critical and important for the performance of HHM CT. The objective of this study is to present a 9 MeV HHM CT prototype based on a high-average-current photo-injector in which X-rays with about 70μm focal spot size are produced via using tightly focused electron beams with 65/66μm beam size to hit an optimized tungsten target.

Cytological analysis of ginseng carpel development.

Panax ginseng Meyer, commonly known as ginseng, is considered one of the most important herbs with pharmaceutical values due to the presence of ginsenosides and is cultivated for its highly valued root for medicinal purposes. Recently, it has been recognized that ginseng fruit contains high contents of triterpene such as ginsenoside Re as pharmaceutical compounds. However, it is unclear how carpel, the female reproductive tissue of flowers, is formed during the three-year-old growth before fruit is formed in ginseng plants.