分类: 核科学技术 >> 粒子加速器 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: The operation of the HIRFL accelerator has shown that the beam transmission efficiency of the sector focusing cyclotron (SFC) injector line is rather poor. Beam simulations have been performed to investigate the possible causes for this low transmission. It is predicted that the property of transversal coupling of the ion beam from electron cyclotron resonance (ECR) ion source can be an important factor to degrade the beam quality by increasing the beam emittance, resulting in a serious particle loss. An improved operation scheme for the SECRAL associated line has been proposed, and the corresponding experiment was carried out. This paper presents the test results.
分类: 核科学技术 >> 核探测技术与核电子学 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: A readout electronics has been developed for the silicon strip array detector system of HIRFL-CSR-ETF. It consists of 48 front end electronics (FEE) boards, 12 PXI-DAQ boards and one trigger board. It can implement energy and time measurements of 4608 channels. Each FEE board is based on 6 ASICs (ATHED), which implements energy and time measurements of 96 channels. The PXI-DAQ board meets requirements of high-speed counting and amount of readout channels and can process signals of 4 FEEs. The trigger board is developed to select the valid events. The energy linearity of the readout electronics is better than 0.3% in the dynamic range of 0.10.7 V. In the test with a standard triple alpha source, the energy resolution was 1.8% at 5.48 MeV. This readout electronics enables the silicon strip array system to identify particles of A 14.
分类: 物理学 >> 核物理学 提交时间: 2016-09-13
摘要: Aiming at the observation of cosmic-ray chemical composition at the "knee" energy region, we have been developinga new type air-shower core detector (YAC, Yangbajing Air shower Core detector array) to be set up at Yangbajing (90.522∘ E, 30.102∘ N, 4300 m above sea level, atmospheric depth: 606 g/m2) in Tibet, China. YAC works together with the Tibet air-shower array (Tibet-III) and an underground water cherenkov muon detector array (MD) as a hybrid experiment. Each YAC detector unit consists of lead plates of 3.5 cm thick and a scintillation counter which detects the burst size induced by high energy particles in the air-shower cores. The burst size can be measured from 1 MIP (Minimum Ionization Particle) to 106 MIPs. The first phase of this experiment, named "YAC-I", consists of 16 YAC detectors each having the size 40 cm × 50 cm and distributing in a grid with an effective area of 10 m2. YAC-I is used to check hadronic interaction models. The second phase of the experiment, called "YAC-II", consists of 124 YAC detectors with coverage about 500 m2. The inner 100 detectors of 80 cm × 50 cm each are deployed in a 10 × 10 matrix from with a 1.9 m separation and the outer 24 detectors of 100 cm × 50 cm each are distributed around them to reject non-core events whose shower cores are far from the YAC-II array. YAC-II is used to study the primary cosmic-ray composition, in particular, to obtain the energy spectra of proton, helium and iron nuclei between 5×1013 eV and 1016 eV covering the "knee" and also being connected with direct observations at energies around 100 TeV. We present the design and performance of YAC-II in this paper.