Accurate Formulae for the Cross-Section Data for the Radio-Halogen I-123 from Cyclotron Production

123I is the most widely used cyclotron-produced radio-halogen in medical research. In this paper, excitation function formulae for the nuclear reactions of 123I production are introduced. 124Te (p, 2n)123I and 127I (p, 5n)123Xe → 123I nuclear reactions have been studied as a function of the energy of the neutrons. Both two formulae were created using the least squares regression of the experimental cross sections data, which were obtained from the Experimental Nuclear Reaction Data EXFOR Database version of 2023. The proposed formulae were evaluated using two statistical indicators for goodness-of-fit. High agreement was observed between the empirical and experimental results for both nuclear processes.

Model-based cross section calculations on production of 43,34Sc,45Ti, 51Cr, 54Mn, and 55Fe radioisotopes

A cross section database on excitation functions of reactions produced by charged particles is essential for many areas of nuclear research. Particularly, accurate knowledge on nuclear cross sections for the cyclotron production of radioisotopes is very important for nuclear medicine. In the present paper, the cross section calculations for the production of^(43),^(34)Sc,^(45)Ti,^(51)Cr,^(54)Mn, and^(55) Fe radioisotopes were carried out by the use of ALICE/ASH code using the Fermi gas model, Kataria Ramamurthy Fermi gas model, and superfluid nuclear model for nuclear level density. Thereby, these model calculations were compared with the available measured data.

Calculation of production cross sections of γ-rays from thermal-neutron captures

The calculation methods of production cross sections of γ-rays for thermal-neutron captures are briefly presented. The check of intensity balance is made. The examples are given to illustrate its application.

M_(αβ) X-ray production cross sections of Pb and B iby 9–40 keV electron impact

The experimental data of Mαβ X-ray production cross sections for Pb and Bi by 9–40 keV electron impact have been given. Thin films with thick carbon substrates are used in the experiment. The effects of target structure on the Mαβ X-ray production cross sections are corrected by using the Monte Carlo method. The corrected experimental data are compared with calculated cross sections in terms of the distorted-wave Born approximation(DWBA) theory. The measured Mαβ X-ray production cross sections for Pb and Bi are lower than the DWBA calculations. The atomic relaxation parameters used in comparing the DWBA values with experimental results affect the degree of difference.

Production of p-rich nuclei with Z = 20-25 based on radioactive ion beams

Within the framework of isospin-dependent Boltzmann-Langevin model,the production cross sections of proton-rich nuclei with Z=20-25 are investigated.According to the reaction results for different isospin of projectiles^(48)Ni,^(49)Ni,and^(50)Ni,proton-rich fragments tend to be more easily produced in reactions with the protonrich projectile^(48)Ni.The production cross sections of the unknown nuclei in the vicinity of the projectile are sensitive to incident energy.It is observed that incident energy of 345 MeV/u is appropriate for producing proton-rich nuclei with Z=20-25.In projectile fragmentation reactions based on the radioactive ion beam of48Ni at 345MeV/u,several unknown proton-rich nuclei near the proton drip line are generated in the simulations.All these new nuclei are near-projectile elements near Z=28.The production cross sections of the new nuclei^(34)Ca,37,38Sc,^(38)Ti,^(40,41,42)V,^(40,41)Cr,and^(42,43,44,45)Mn are in the range of 10-2-102mb.Hence,projectile fragmentation of radioactive ion beams of Ni is a potential method for generating new proton-rich nuclei with Z=20-25.

Electron-Positron Pair Production in Electro-Magnetic Field

At very high energies, pair production formation (γ + N → e+e-) exhibits a variety of intriguing properties. Analytically and quantitatively, the formation of Electron-Positron pairs in the Electro-Magnetic field of light nuclei has been calculated. In Ultra-Relativistic (UR) areas of incident photon energy, applying the resulting formulas to the energy distribution of the (e-, e+) operation. When we compare the results, we can observe that the Magnetic field of the target nucleus is more efficacious than the Electric field of the nucleus in the (e-, e+) operation. Furthermore, we can show that in Pair Production operation, the Differential Cross Section (DCS) owing to the target nucleus’s Electric Quadrupole (EQ) and Magnetic Octupole (MO) are bigger than the Differential Cross Section (DCS) attributable to the target nucleus’s Electric Charge (EC) distribution and Magnetic Dipole (MD).

Theoretical study on fusion dynamics and evaporation residue cross sections for superheavy elements

The nuclear dynamical deformation,the fusion probability and the evaporation residue(ER) cross sections for the synthesis of superheavy nuclei are studied with the di-nuclear system model and the related dynamical potential energy surface.The intrinsic energy and the maximum dynamical deformations for48Ca+248Cm are calculated.The effect of dynamical deformation on the potential energy surface and fusion is investigated.It is found that the dynamical deformation influences the potential energy surface and fusion probability significantly.The dependence of the fusion probability on the angular momentum is investigated.The ER cross sections for some superheavy nuclei in48Ca induced reactions are calculated and it is found that the theoretical results are in good agreement with the experimental results.

K Shell and L Subshell Photoeffect Cross-Sections of Some Elements in the Atomic Range 50≤Z≤65 at 59.5 keV

In this study,K and L shell photoeffect cross-sections were measured for the elements in the range of 50≤Z≤65at 59.5keV.These photoeffect cross-sections were measured by using the experimentalσKαproduction cross-section values measured in this paper and two different K shell fluorescence yield values in the literature.The results were compared with the calculated theoretical values.The values were plotted versus atomic number.

A method of analysing experimental data of nuclear reaction cross sections

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On Self-Similarity of Top Production at Tevatron

This paper presents the results of analysis of the D? 1.0 fb-1 data on top-quark differential cross section measurements at the Fermilab Tevatron collider at √s= 1960 GeV in the framework of z-scaling approach. The flavor independence of scaling function Ψ(z)observed in pp and pp interactions over a wide collision energy range √s= 19-1960 GeV has been verified. This property of Ψ(z) was found for different hadrons – from π-mesons up to Υ particles. The flavor independence of Ψ(z) is used as indication on self-similarity of the top-quark production. A tendency to saturation of Ψ(z) at low z for top-quark production has been confirmed. Momentum fraction x1 of the incoming (anti)protons as a function of the scaled transverse momentum pT/m and masses of heavy mesons is studied. We anticipate that the data on low- and high-pT inclusive spectra of the top-quark production at the Tevatron and LHC energies could be of interest to verify self-similarity over a wide range of masses and different flavor content of produced particles.

中子诱发伽马产生截面测量中的谱分析技术

在中子反应截面测量中,瞬发γ射线法是一种通过测量核反应放出的特征γ射线来得到截面数据的方法,这种方法能够避免竞争反应道产生的干扰.但是瞬发γ射线法为在线实验,本底来源丰富,造成了在线实验谱分析难度大,结果不确定性高.本文研究了使用瞬发γ射线法测量中子诱发伽马产生截面的谱分析技术,总结了中子诱发伽马产生截面测量中不同特征峰形成的物理过程,降低了在线实验谱处理过程中计算效应峰净面积的不确定度.通过采用各种响应函数来对全能峰、本底以及干扰因素进行拟合的方法,精确提取了效应峰的净面积.针对弱峰的净面积,本方法可将峰区域选取引起的波动从30%降低到1%以内,且净面积拟合值与理论值的差距与统计不确定度相当;对于解重峰,本方法所得结果与理论值差距显著低于1%.通过效率曲线分析、拟合优度计算等方法同时验证了谱分析方法的可靠性.

宁夏地区儿童用药品生产配备使用情况现况调查及分析

目的 梳理宁夏地区儿童用药品(包括临床使用的院内制剂)生产、配备使用相关情况,分析宁夏地区儿童用药品方面存在的问题,为完善儿童药品供应保障机制提供合理建议。方法 主要通过问卷调查、访谈、数据提取等方式,对宁夏地区有关部门、20家医疗机构和3家药品生产企业进行问卷调查及访谈。结果 宁夏地区3家企业生产涉及儿童药品品种58个、规格64个,主要以口服固体剂型为主(57种)。20家医疗机构共配备药品品规166~319种,综合医院平均配备药品171.5种,妇幼保健机构平均配备药品62.5种。需要增加药品说明书儿童用药信息的药品97种,需要改进剂型的药品23种,需要改规格的药品45种。结论 医疗机构对修订儿童用药说明书需求较大,需要增加儿童用药品的规格和剂型。应从政策制定、医疗机构临床评价、社会公众宣传多方面入手,为全面保障儿童用药安全、规范使用提供支持。

Product polarization and mechanism of Li + HF(v=0, j=0) → LiF(v', j') + H collision reaction

A state-to-state dynamics analysis for the Li＋HF （v = 0, j = 0）→LiF （v’, j’）＋H collision reaction has been performed through quasiclassical trajectory （QCT） calculations. It is found that the differential cross section （DCS） of the LiF products from the title reaction is preferentially backward scattering for v’=0, yet forward scattering for v’=1 and 2. For v’=3, the DCS exhibits forward, backward, and sideways scatterings. The variation of the internuclear distances and angles along the propagation time reveals that more than 99.08% of reaction trajectories undergo the direct reaction mechanism. The values of the polarization parameters a1-{1} and a0{2} demonstrate that the product rotational angular moment j’ is not only aligned perpendicular to the reagent relative velocity vector k, but also oriented along the negative y axis. These product polarization results agree well with the recent quantum mechanical studies. The mechanism of these results was proposed and discussed in detail.

Theoretical prediction of energy dependence for D+BrO→DBr+O reaction:The rate constant and product rotational polarization

A quasi-classical trajectory（QCT） calculation is used to investigate the vector and scalar properties of the D ＋ Br O → DBr ＋ O reaction based on an ab initio potential energy surface（X1A state） with collision energy ranging from 0.1 kcal/mol to 6 kcal/mol. The reaction probability, the cross section, and the rate constant are studied. The probability and the cross section show decreasing behaviors as the collision energy increases. The distribution of the rate constant indicates that the reaction favorably occurs in a relatively low-temperature region（T 〈 100 K）. Meanwhile, three product angular distributions P（θr）, P（φr）, and P（θr, φr） are presented, which reflect the positive effect on the rotational angular momentum j＇ polarization of the DBr product molecule. In addition, two of the polarization-dependent generalized differential cross sections（PDDCSs）, PDDCS00 and PDDCS20, are computed as well. Our results demonstrate that both vector and scalar properties have strong energy dependence.

Numerical analysis on element creation by nuclear transmutation of fission products

A burnup calculation was performed to analyze the Apr`es ORIENT process, which aims to create highlyvaluable elements from fission products separated from spent nuclear fuels. The basic idea is to use nuclear transmutation induced by a neutron capture reaction followed by a β-decay, thus changing the atomic number Z of a target element in fission products by 1 unit. LWR(PWR) and FBR(MONJU) were considered as the transmutation devices. High rates of creation were obtained in some cases of platinum group metals(44Ru by FBR,46 Pd by LWR) and rare earth(64Gd by LWR,66 Dy by FBR). Therefore, systems based on LWR and FBR have their own advantages depending on target elements. Furthermore, it was found that creation rates of even Z(= Z + 1) elements from odd Z ones were higher than the opposite cases. This creation rate of an element was interpreted in terms of "average 1-group neutron capture cross section of the corresponding target element σc Z defined in this work. General trends of the creation rate of an even(odd) Z element from the corresponding odd(even) Z one were found to be proportional to the 0.78th(0.63th) power of σc Z, however with noticeable dispersion. The difference in the powers in the above analysis was explained by the difference in the number of stable isotopes caused by the even-odd effect of Z.

Production cross sections of the superheavy nucleus 117 based on the dinuclear system model

Within the framework of the dinuclear system model, the capture of two colliding nuclei, and the formation and de-excitation process of a compound nucleus are described by using an empirical coupled channel model, solving the master equation numerically and the statistical evaporation model, respectively. In the process of heavy-ion capture and fusion to synthesize superheavy nuclei, the barrier distribution function is introduced and averaging collision orientations are considered. Based on this model, the production cross sections of the cold fusion system ^76-82Se＋^209Bi and the hot fusion systems ^55Mn＋^238U, ^51V＋^244pu, ^59Co＋^232Th, ^48Ca＋^247-249Bk and ^45Sc＋^246-248Cm are calculated. The isotopic dependence of the largest production cross sections is analyzed briefly, and the optimal projectile-target combination and excitation energy of the 1n-4n evaporation channels are proposed. It is shown that the hot fusion systems ^48Ca＋^247-249Bk in the 3n evaporation channels and ^45Sc＋248Cm in the 2n-4n channels are optimal for synthesizing the superheavy element 117.

Production cross section of neutron-rich calcium isotopes in heavy ion collisions

Based on the isospin-dependent quantum molecular dynamics model along with the GEMINI model, heavy-ion collisions at intermediate energies are studied. We calculate the production cross sections of different fragments for reactions of 112Sn＋112Sn and 124Sn＋124Sn at different beam energies. The species and production cross sections of neutron-rich isotopes are generally dependent on the isospin of the system and the incident energies. The isotopes 48Ca and 54Ca are more productive for the neutron-rich system at 30 to 150 MeV/nucleon.

Isotopic production cross sections of fragmentation residues produced by ^(18)O ions on a carbon target near 260 MeV/nucleon

The isotopic cross sections of residual nuclei produced in fragmentation reactions of ^(18)O projectiles impinging on a carbon target at energies near 260 MeV/nucleon were measured at the HIRFL facility in Lanzhou(China).A full identification of atomic and mass numbers of fragments was achieved from the determination of their magnetic rigidity,energy loss,and time of flight.The production cross sections for a dozen of nitrogen,carbon,and boron isotopes were determined with uncertainties below 30% for most of the cases.The obtained cross sections for N and B isotopes show a rather good agreement with previous experimental data obtained with different projectile energies.The cross sections for some C isotopes seem to exhibit a dependence on the projectile energy.A comparison of the data and several theoretical model calculations are presented.

单个类矢量B夸克在紧凑型线性对撞机上通过bZ衰变道的产生

许多超出标准模型的新物理都预测了新的类矢量夸克.它们会在高能对撞机上产生独特的信号.基于模型无关的框架,研究了单态的类矢量B夸克在质心能量为3 TeV的紧凑型线性对撞机上的单个产生过程.重点研究e^(+)e^(-)→B→Zb过程以及Z玻色子两种衰变道(Z→l^(+)l^(-)和Z→v)的末态信号.通过对信号和标准模型背景的分析,分别给出了在年积分亮度为5 ab^(-1)下对B夸克质量和耦合参数的排除限制和发现范围.数值结果表明,未来的高能量线性对撞机可以作为探测类矢量B夸克的电弱耦合的理想场所.

近玻尔速度不同离子碰撞产生Al的KX射线

在玻尔速度附近能区,测量了H^(+),He^(2+)和I^(22+),Xe^(20+)离子作用于Al靶时碰撞激发靶的K壳层X射线.得到了相应X射线的发射截面,并与不同理论模型进行对比.研究表明,单核子能量相同时,轻离子入射激发的X射线产生截面比高电荷态重离子轰击时小了大约4个数量级.质子、He^(2+)离子激发的实验截面可以由ECPSSR理论来很好的估算,而I^(22+),Xe^(20+)的实验结果与考虑有效电荷、低速库仑偏转修正的BEA理论计算符合较好.