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971.
The current design of the CSNS/RCS beam collimation system consists of a two-stage betatron collimation and a single momentum collimator. This paper summarizes various aspects of collimator design, including collimation principle and layout, material choice and collimator mechanical structure, etc. At last,radiation and thermal analysis are carried out to illustrate the feasibility of the current beam collimation scheme. 相似文献
972.
JIAO Yi GUAN Xia-Ling SATOGATA Todd FANG Shou-Xian WEI Jie TANG Jing-Yu CHEN Yuan 《中国物理C(英文版)》2010,34(3)
A proton therapy facility based on a linac injector and a slow cycling synchrotron is proposed.To achieve effective treatment of cancer,a scanning gantry is required.The flexible transmission of beam and high beam position accuracy are the most basic requirements for a gantry.The designed gantry optics and scanning system are presented.Great efforts are put into studying the sensitivity of the beam position in the isocenter to the element misalignments.It shows that quadrupole shift makes the largest contribution and special attention should be paid to it. 相似文献
973.
974.
975.
976.
The current design of the CSNS/RCS beam collimation system consists of a two-stage betatron collimation and a single momentum collimator. This paper summarizes various aspects of collimator design, including collimation principle and layout, material choice and collimator mechanical structure, etc. At last, radiation and thermal analysis are carried out to illustrate the feasibility of the current beam collimation scheme. 相似文献
977.
The cross sections of the fragments produced in the projectile fragmentation reactions of the even calcium isotopes from A=36 to A=52 are calculated using the statistical abrasion ablation model.The neutron skin thickness are studied by investigating the fragments isotopic cross section distributions.The neutron-skin thicknesses of the calcium isotopes have a good linear correlation to the peak positions of their fragment isotopic cross section distributions.The correlation between the neutron skin thickness and the neutron density distributions of 48 Ca is investigated by introducing a parameter to adjust the diffuseness parameter in the fermi-type density distribution. 相似文献
978.
Investigation of the Potts Model on Triangular Lattices by the Second Renormalization of Tensor Network States 下载免费PDF全文
We employ the second renormalization group method of tensor-network states to investigate thermodynamic properties of the ferromagnetic and antiferromagnetic Potts model on triangular lattices. From the temperature dependence of the internal energy and the specific heat, both the critical temperatures and critical exponents are evaluated. For the q = 3 antiferromagnetic Potts model, the critical temperature is found to be Tc = 0.627163±0.000003, which is at least one order of magnitude more accurate than that obtained by other methods. 相似文献
979.
A simulation on the electric field distribution near the electrode is proposed to explain the reason for using nanosized carbon black mixed with ethylene vinyl acetate, as the electrode could lead to more charge injection into the polymer than using a deposited metal electrode. The electrode is simplified to a layer of conductive semi-spheres with fixed size and constant electric potential. By using the finite element method, it is found that both the size of the semi-spheres and the distance between adjacent semi-spheres could dramatically influence the electric field near the surface of the spheres; these are considered to be the two decisive factors for the charge injecting rate at electrodes of various materials. 相似文献
980.
K-Shell Spectra from CH-Tamped Aluminum Layers Irradiated with Intense Femtosecond Laser Pulses 下载免费PDF全文
X-ray spectra of H-like and He-like aluminum ions from aluminum buried in CH layers irradiated with 30fs, 200 TW laser are measured. The electron temperature and density are derived from line ratios of the He-α resonance line to its satellite lines. Typical temperatures of 490-646 eV and electron densities up to 7 × 10^20 cm-3 are obtained. The results show that the electron density increases and temperature decreases with the increasing CH thickness. 相似文献