1980 Vol. 4, No. 6

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Review
PREFORMANCE OF THE LARGE AREA PLASTIC SCINTILLATION COUNTER
Chen Ying-xuan, Jiang In-lin, Ren Guo-xiao, Ma Yu-qian, Wu Mei, He Chang-xiao, Shen Pei-ruo
1980, 4(6): 683-688.
Abstract:
Collective form of scintillation light was investigated for 75×37 cm2 plasticscintillator. On the basis of these experiments, ten scintillation counters were con-structed. The construction and performance of these counters are described in thisarticle, and the principle of design is also discussed.
A SIX INPUTS PROGRAMMABLE TRIGGER LOGICAL CIRCUIT
Ding Hui-liang, Yang Xi-rong, Yu Zhong-qiang, Gu Song-hua
1980, 4(6): 689-693.
Abstract:
A Six Inputs Programmable Trigger Logical Circuit (NIM Standard) has beendeveloped using a ECL fully decoded random access memory (RAM) E855 64×1.This circuit can realize various logical functions of the inputs N≤6. While varyinglogical conbinations of the inputs, what is required is only loading the memories againand without hardware or link modifications. It can replace the logical NIM circuitsof the inputs N≤6 which ape used in the on-line experiments of the high energyphysics. Based on this principle, it can be expected to develop a low prices, facile andlarge scale trigger logical system in order to satisfy the requirements of the high energyphysics counter experiments. In this circuit the input signal is standard NIM level with the pulse width≥4 ns.The output signal is also standard NIM level. The output can supply 32 mA currentand connect two 50 Ω loads to form the bridge output. The circuit works with both strobeand no strobe format.
ASSESSMENT OF THE RADIOLOGICAL IMPACT OF THE 50 GeV BPS1) ON ITS ENVIRONMENT
Ye Si-zong, Zhu Yu-cheng, Liu Gui-lin, Shao Bei-bei, Xiao Ting-han
1980, 4(6): 694-705.
Abstract:
The site proposed for the construction of the 50 GeV Proton Synchrotron of theAcademia Sinica near Beijing is close to residential areas and places with a high cul-tural and touristic value. The impact of the construction and operation of the accele-rator on the environment and in particular the radiological impact is of Prime concernto the authorities who licence and support the project. It is shown in the present re-port that the influence on the area outside the fence of the proposed site is indeedvery small: the stray radiation level can be kept below 20 mrem/y outside the fence,and the radioactivity released in air will not, in the most exposed location outsidethe accelerator area, give rise to a submersion does of more than 10mrem/y. Provid-ed some precautions are taken. The release of activity by water will not result inactivity concentrations of more than one tenth of the maximum permissible concentra-tions according to the legislation of the People' s Republic of China. The estimationsin this report have been based both on calculations and on experience with the CERNand other accelerators. The conclusions arrived at confirm that the radiological im-pact on the environment of high-energy accelerators of such beam powers(~20 kW)are insignificant.
THE PARAMETERS AND ELECTRICAL TOLERANCE ANALYSIS FOR THE SINGLE BUNCHER SYSTEMS
Wei Kai-yu
1980, 4(6): 706-714.
Abstract:
This paper has analysed the relation of the parameters of single buncher systemsand has calculated the electrical tolerance deviations of buncher and preinjector, andthe paper also has discussed the effect of the electrical errors to the energy spectrumof Linac beam.
MULTIPLE SCATTERING THEORY AND HIGH ENERGY p-p ELASTIC SCATTERING
Li Yang-guo, Zhang Yu-shun, Chen Xiao-tian, Yuan Tu-nan
1980, 4(6): 715-723.
Abstract:
In this paper, we use the Glauber theory of multiple scattering in the complexsystems to analyse high energy p-p elastic scattering. Suppose that proton consists ofthree stratons. Under the rigid projector approximation and supposing that the dis-tribution of straton in proton is a simple Gaussian we give the first order, second order,third order……etc. multiple scattering amplitude. With this result, we have calculatedthe angular distribution of p-p, elastic scattering in Ep=200, 280, 1500 GeV. Theseresults indicate that p-p elastic scattering can be regared as the multiple scatteringbetween stratons.
THE TIME-DEPENDENCES OF THE STATIC SOLUTION OF SU(2) AND SU(3) GAUGE THEORY AT THE PRESENCE OF STATIC EXTENDED SOURCE
Dong Fang-xiao, Zhou Xian-jian, Huang Tao, Xue Pei-you
1980, 4(6): 724-734.
Abstract:
In this paper, we discussed the time-dependence of the static solution of SU(2) and SU(3)gauge theory at the presence of static extended source. Introducing onenew gauge invariance quantity and using the consistence of the time-dependence betweena new gauge convariance quantities and the gauge potential, we deduced more exactlythe time-dependence of static solution than the reference [1] did. Furthermore, weobtained the time-dependences of the static solutions of the SU(3)gauge theory at thepresence of the static extended source.
MONTE-CARLO SIMULATION OF COSMIC RAY ANTIPROTON INTENSITY
Ding Lin-kai, Zhu Qing-qi
1980, 4(6): 735-740.
Abstract:
Using Monte-Carlo method, the propagation of cosmic ray hadrons throughatmosphere is simulated. The aim is to study. the production of NN in strong interac-tions beyond the accelerator energy range and to see whether there is certain fractionof antiprotons by means of comparing the calculated and measured cosmic ray anti-proton intensity at 3200m above sea level. The calculated spectra of cosmic ray p,π±,μ at mountain altitude and at sea level are shown to agree with the measured ones.Some discussions on the results are given.
THE POSSIBLE EFFECT OF PAIRING ON YRAST TRAPS
Zhang Xi-zhen
1980, 4(6): 741-743.
Abstract:
The possible effect of monopole on Yrast traps is studied and the variation ofenergy gap with angular momentum I is calculated using a Woods-Saxon potential.
A CORRELATIVE TREATMENT OF DYNAMICS AND DIFFUSION EQUATIONS IN DEEP INELASTIC COLLISIONS
Zhong Ji-quan
1980, 4(6): 744-751.
Abstract:
It is possible to determine the relaxation time and transport coefficients from thefriction coefficients based on the correlation between the dynamics and diffusion equa-tions. The calculations of the relaxation time of angular momentum and the angluarmomentum transport coefficients indicate that, such a method is convenient for dis-cussing the dissipation and statistic fluctuation in heavy-ion collisions.
VELOCITY CURRENT DISTRIBUTION FOR FAST ROTATION NUCLEI
Wu Xi-zhen, Zhang Xi-zhen, Zhuo Yi-zhong, Feng Ren-fa
1980, 4(6): 752-760.
Abstract:
In this work the velocity current distribution is calculated on the basis of exactsolution of the cranked anisotropic harmonic oscillator by including ΔN=2 at the re-quirment of isotropic velocity distribution. We study the character of velocity cur-rent distribution for the nuclei with high speed rotation. We also discuss the effectof the self-consistency condition.
THE LARGE MOMENTUM BEHAVIOR OF THE PION WAVE FUNCTION AND THE PION ELECTROMAGNETIC FORM FACTOR
Huang Chao-shang
1980, 4(6): 761-766.
Abstract:
In this paper we assume that QCD is the underlying theory of the strong inter-action. Applying the methods of the operator product expansion and the renormaliza-tion group, we examine and obtain the large momentum behavior of the Bethe-Salpeterwave function and the electromagnetic form factor of the π meson.
THE ISOBAR EXCITATION MECHANISM OF THE PION SINGLE CHARGE EXCHANGE REACTION
Liu Bo, Zhang Zong-ye
1980, 4(6): 767-770.
Abstract:
We have studied the pion single charge exchange reaction 13C(π+, π0) 13Ng.s. whichcan reach to isobaric analog state by using the isobar excitation mechanism. The angle-integrated cross sections is calculated. Theoretical results fit the experimental dataquite well.
SELECTION OF THE MEASURING TIME IN THE ABSOLUTE COUNTING OF RADIOACTIVITY
Feng Xi-zhang, Zhao Zhen-lan, Tang Nai-xun
1980, 4(6): 771-773.
Abstract:
The present paper pionted out that in the measurement of the number of atomsof a radioactive isotope in a sample at time t0, the error introduced through the in-accuracy of its decay constant (λ) can be reduced to a much smaller value by thecareful selection of the time of measurement or measurements of its radioactivity ataround one life time (1/λ) after t0 and doing the calculation.
PLANAR MULTIPOLE FIELD OF A PERMANENT MAGNET SYSTEM WITH MULTI-SEGMENTED RING STRUCTURE
Liu Mao-san, Chen Ren-huai, Wu Wen-tai, Li Shu-zhen
1980, 4(6): 774-777.
Abstract:
Expressions for the calculation of a planar permanent magnetic multipolewith multi-segmented ring structure are derived under the assumption of homogeneousmagnetization. Two types of magnets have been considered: the fixed-field type andthe field adjustable type.
THE ADIABATIC-BORN APPROXIMATION OF THE OPTICAL MODEL FOR DEFORMED NUCLEI
Yang Ze-sen
1980, 4(6): 778-783.
Abstract:
Scattering amplitudes are determined in a manner similar to DWBA, but the dis-torted wave function here is found from adiabatic hypothesis. The structure of thescattering amplitudes is still similar to that obtained from adiabatic approximation. butthe main deficiency of the latter, namely the independence of the inelastic amplitudeson the energy loss, is overcome.
ON THE MECHANISM OF BACKBENDING IN NUCLEI 162,164Er, 164,166Yb, AND 168Hf
Zhang Jing-ye, Zhang Xi-zhen
1980, 4(6): 784-787.
Abstract:
Grosse, Stephens and Diamond stated out, basd on the analysis of the behavior ofbackbending in odd A nuclei, the mechanism of backbending for even-even neighborscan be determined. In fact, however, there exist some difficulties. For instance, it is unable to deter-mine the mechanism of backbending for nuclei Er, Yb and Hf throughsuch an analysis. In this letter, using HFB Cranking model, the aligned angular mo-mentum i(ω) and critical rotation frequency ωc have been calculated with some con-sideration of the blocking effect. Through a comparison between theoretical resultsand experimental data, it can be concluded that the backbending occuring in these nuc-lei is mainly caused by the rotation alignment of a vi13/2 pair, not πh9/2 pair.
A SIMPLE MODEL FOR STUDYING THE STRETCH AT SCISSION POINT IN FUSION-FISSION AND QUASIFISSION INDUCED BY HEAVY-IONS
Wang Zheng-da, Xu Shu-wei, Miao Rong-zhi
1980, 4(6): 788-794.
Abstract:
Assuming that the kinetic energy of relative radial motion of fragments can beneglected during the scission process, so that the adiabatic approximation condition isassumed to be fulfilled, and the fragments have rotationally symmetric quadrupole de-formation only. We have obtained three equations, which govern the motion of the frag-ments at scission point. Solving these simple algebra equations, we can obtain thescission point stretch, and evaluate the total kinetic energy of the emitted fragments.The calculated results are in agreement with most experimental data for the averagetotal kinetic energy of fragments for heavy nuclei, which are emitted in the process offusion-fission and quasi-fission i.e. completё damping process of DIS induced byheavy-ions.