Study of Yields for Target Fragments From the Reaction of Iron With 80MeV/u 16O Ions

Produchon yields were determined for 25 abet fragments produced from the reaction of iron with 80 MeV/u ¹⁶O ions. From these data, charge distribution and mass yield distribution have been deduced. The experimental results are compared with those reported from our previous work. It is found that the width parameter σ_z and the most probable charge Z_p of the charge distribution increase slowly with increasing bombarding energy. The mass yield distribution is discussed in terms of the concepts of limiting fragmentation and factorization.     

TESTING GLUON DISTRIBUTION FUNCTION OF HADRONS IN LARGE PT PROCESS WITH DIRECT PHOTON EMISSION

In this paper we disscuse disscuse the physicsical aspect of cross-section differences Δ_AB^cγ=dσ(AB→cγX)-dσ(AB→cγX) and give the simple rules to select the elementary subprocesses which contribute to cross-section differences.
We bind a way to test the gluon distribution functions of hadrons through the measurement of cross-section difference or combination of cross-section differences in the large P_T process with direct photon emission. Moreover we obtain simple relations between each combination of cross-sections and the corresponding gluon distribution functions of proton, neutron, pion and daon:
G_p⁸(x)/(Δ_pp^hγ－Δ_pp^hγ)=G_n⁸(x)/(Δ_pp^hγ)=G_π⁸(x)/(Δ_π+p^hγ+Δ_π－p^hγ=G_K⁸(x)/(Δ_K+p^hγ+Δ_K－p^hγ)which are expected to be test in experiment.     

Correlation between fractional independent yields and neutron-to-proton ratio of fission products in low energy fission

Fractional independent yields of fission products in the thermal neutron-induced fission of²³³U,²³⁵U,²³⁹Pu,²⁴¹Pu and in the spontaneous fission of²⁵²Cf have been correlated with the neutron-to-proton ratio of the fission products. The yields of the products from a fissioning system, when plotted as a function of neutron-to-proton (N/Z) ratio of fission preducts, fall on two Gaussian distribution corresponding to light and heavy fission products. The centroids of the distribution or the most probable value of neutron-to-proton ratio is found to be very close to theN/Z of the fissioning nucleus. From the most probable value ofN/Z the various parameters of charge distribution e.g. most probable massA _p, most probable chargeZ _p, the mass dispersionσ _Aand the charge dispersionσ _Zhave been obtained and are in good agreement with the experimental values ofA _pandZ _p.     

RADIOCHEMICAL INVESTIGATION OF MASS DISTRIBUTIONS IN 12C-INDUCED FISSION OF 209Bi AND 238U

The yields of 15 and 17 fission, products have been obtained by radiochemical determinations in ¹²C-induced fission of ²⁰⁹Bi and ²³⁸U respectively. From these data, the mass distributions of fission fragments are calculated based on three different hypotheses for the charge distribution. The results seem to indicate that the hypothesis of equal charge displacement gives the best fit to the Gaussian distribution for the masses of the fission fragments. By comparison with the mass distributions for ²⁰⁹Bi (¹²C, f), ²³⁸U(¹²C, f) and ¹⁹⁷Au(¹²C, f) in our early measurement, we find that for fission parameter Z²/A>37, the width of the mass distributions increases with Z²/A rapidly.     

Angular distributions of light projectile fragments in deep inelastic Pb + Em interactions at 160 A GeV

The nuclear emulsion was exposed at CERN by the lead projectile at 160 A GeV. The angles between any pair of fragments with Z = 2-4 have been measured in the emulsion plane for the events which did not contain heavy fragments. The constant characterizing the normal angle (J) distribution of the fragment momentum projection onto the emulsion plane with respect to initial projectile momentum p₀ is found to be C_J = (0.37 - 0.02) mrad. Corresponding value C₀ = (121 - 6) MeV/c of nucleon momentum distribution in the lead nucleus coincides with that expected from Fermi momentum distribution for this nucleus. The peak in the pair-angle distribution of double-charged fragments, ⁸Be M 2!, is presented for the region of small angles (<0.1 mrad). The fraction of !-particles coming from the decay of the ground state ⁸Be is found to be (13 - 2)% of their whole number.     

函数的H-导数和分形动力学

 给出了函数的Hausdorff测度与H-导数。从而，为开展自给的分形动力学提供了解析的数学工具。同时，给出了分形动力学的演化方程组并做了初步讨论与分析。     

Complex Fragments Emitted in Reactions of 46．7MeV/u 12C on 197Au,115In and 58Ni

Energy spectra of complex fragments emitted in the reactions of 46.7MeV/u ¹²C with different targets ¹⁹⁷Au,¹¹⁵In and ⁵⁸Ni have been measured by telescopes,consisting of a gis ionization counter followed by a position Sensitive semiconductor detector.Tha most probable kinematical energies.E_p of complex fragments and temperature parameters of long－live intermediate systems have been deduced by complex fragment ernergy spectra.The experimental values of E_p are lower than the calculated ones by E=V_coul+2T.The experimental values of complex fragment yields can be reproduced by simple A.Friedman statistical evaporation model satisfactorily.     

Experimental Determination of the Radiative Correction Factor Δr and Phenomenological Analyses

In this paper the experimental value of radiative correction Δr was derived from the new data of sin ²θ_w and W boson mass M_w given by LEP,CDF and other collaborations.A careful comparison of (Δr)_exp with the standard model expectation was carried out.We first calculated the Δr at full one-loop level,and then the main two-loop contributions were included.More stringent upper bounds on M_t were obtained from the analysis of probability distribution:M_t175GeV at 95%C.L. for a given M_H=100GeV.The effects on N_t from other experimental and theoretical errors were also computed.     

THE STUDY OF SOME NON-SOLATED RESONANCES FOR THE 23Na （p,α）20Ne REACTION

The excitation functions of the ²³Na（p,α₀）²⁰Ne_g·s.and the ²³Na（p,α₁）²⁰Ne_lst reae-tion have been measured from E_p=1 to 2.5 MeV at θ_L=30°,150° and 30°,respectively.Around the resonance at 2.171 MeV,the excitation functions of the（p,α₀）reactionhave been measured at 12 angles,then,some angular distributions have been obtained from these excitation functions.In addition,the angular distribution of the（p,α₀）reaction for the resonance at 2.171 MeV has also been measured directly at energy ofthe resonance peak of the excitation function at 150°.For the resonance at 2.117MeV,the angular distribution have been measured at two energies,one at the energyof the resonance peak of the excitation function at 150°,another at the energy of thehalf maximum point of the resonance peak on the higher energy side.Around the re-sonance at 2.075 MeV,the excitation functions have been measured at 16 angles,andthe angular distribution has been obtained from three excitation functions.The an-gular distributions of the three resonances are not symmetric about 90°,and the posi-tions of the resonance peaks of these resonances varies with the angle of measurement.By means of the compound nucleus theory,discussions have been made for these non-solated resonances.     

Single Particle Schr dinger Fluid and Moments of Inertia of Deformed Nuclei

We have applied the theory of the single-particle Schrodinger fluid to the nuclear collective motion of axially deformed nuclei. A counter example of an arbitrary number of independent nucleons in the anisotropic harmonic oscillator potential at the equilibrium deformation has been also given. Moreover, the ground states of the doubly even nuclei in the s-d shell ²⁰Ne,²⁴Mg,²⁸Si,³²S and ³⁶Ar are constructed by filling the single particle states corresponding to the possible values of the number of quanta of excitations n_x,n_y, and n_z. Accordingly, the cranking-model, the rigid-body model and the equilibrium-model moments of inertia of these nuclei are calculated as functions of the oscillator parameters ω_x,ω_yand ω_z which are given in terms of the non deformed value ω00 , depending on the mass number A, the number of neutrons N, the number of protons Z, and the deformation parameter β. The calculated values of the cranking-model moments of inertia of these nuclei are in good agreement with the corresponding experimental values and show that the considered axially deformed nuclei may have oblate as well as prolate shapes and that the nucleus ²⁴Mg is the only one which is highly deformed. The rigid body model and the equilibrium model moments of inertia of the two nuclei ²⁰Ne and ²⁴Mg are also in good agreement with the corresponding experimental values.     

Projectile Fragmentation in 46.7MeV/u 12C Induced Reactions

The projectile-like fragments emittd from 46.7MeV/u ¹²C induced reactions have been measured.The most probable energies of the PLFs due to the projectile fragmentation can be reproduced within the Abrasion picture.Their parallel momentum distribution widths are found to fulfill the Goldhaber relation and the extraced reduced parallel momentum distribution width σ₀ is 80±10MeV/c,which is close to the value obtained in the relativistic energy region.Futhermore,the values of σ₀ are the same for different reaction systems in our experiment.     

ON THE POSSIBILITY OF W,Z AS COMPOSITE PARTICLES

The relation between the masses of W^± and Z⁰ in a composite model is disscused phenomenologycally. It is shown that any deviation of experimental data from the predicted value of W-S model will be in favour of the composite model.
By using present experimental data, the calculation results show that is W' (the radial excited state of W) exists, then its mass will be greater than (2—5)m_w.     

A MODIFIED SKYRME MODEL

In this paper we study a modified skyrme model with m_π≠0 and compute the static properties of nucleons in this model.The results show that most of theoretical values have been improved,especially 2>^1/2=0.56fm is two times as one from the original Skyrme model and it is close to experimental value.     

Bosonized Vertex Operators Realize Z-F Algebra for Zn Symmetric Belavin R Matrix

From the bosonization of vertex operators for A⁽¹⁾_n－1 face model given by Asai,Jimbo,Miwa and Pugai,using vertex-face correspondence,we obtain bosonized vertex operators for Z_n symmetric Belavin R matrix,which realize the Zamolodchikov-Fadeev algebra for that R matrix.     

INVESTIGATION OF THE NUCLEAR SHADOWING EFFECT IN THE SMALL x REGION

In this paper,we analyse the spatial overlapping behavior of sea quarks of neighboring nucleons in nuclei in the small x region and give a relation between the nuclear shadowing factor R(x,Q²,A) and the spatial overlapping factor ΔV_A(x)/V_A(x).By using this nuclear shadowing factor R(x,Q²,A),we calculate the ratios of the average nuclear structure functions of nuclei ¹²C、⁶³Cu and ¹¹⁶Sn,to the deuteron structure function and obtais a better agreement between the calculated result and the experimental data.     

金属性氧化物LaCuO3的高氧压合成及Cu3+态的XPS研究

 本文在成功地用超高氧压（~6.5 GPa）及高温（~980 ℃）合成和结构测定的基础上，首次对金属性化合物中LaCuO₃中的Cu³⁺离子给予标定，并研究了它与绝缘体中Cu³⁺的区别。本论文中合成的LaCuO₃为金属性化合物，电导率测量表明在大于13 K无超导电性迹象。XPS测量给出了LaCuO₃中Cu2p_3/2内层电子结合能相对于La₂CuO₄或CuO中的Cu²⁺向高结合能方向移动了约2.6 eV，这一量值远大于NaCuO₂（绝缘体）中的Cu2p_3/2相对于CuO中的Cu²⁺移动的值，约为1.3 eV。Auger谱测量表明，LaCuO₃的修正了的Auger参数与CuO的基本相同，但L₃VV的Auger电子动能相对CuO移动了2.8 eV。这些位移说明在金属性化合物LaCuO₃中，Cu³⁺处在八面体位置上，它与近邻的Cu³⁺连成单个Cu—O—Cu桥，因此可作为对比p型高T_c含铜氧化物的XPS谱的标准。     

Fine-Structure Splittings of Nitrogen Isoelectronic Sequence： Competitions among Spin-Orbit Interactions, Breit Interactions and Electron Correlations

Using the multi-configuration Dirac-Fock self-consistent field method and the relativistic configuration interaction method with quantum-electrodynamics corrections performed by the GRASP code, we calculate the fine-structure energy levels of the ground-state configuration （1s^22s^22p^3） of the nitrogen isoelectronic sequence, according to the L-S coupling scheme with atomic number Z up to 22. Based on the calculated results, we elucidate the mechanism of the orderings of fine-structure energy levels of 2^ D3/2,5/2 and 2^P1/2,3/2 respectively, i.e. for 2^D3/2,5/2 orderings, the competition between the spin-orbit interactions and the Breit interactions; for 2^P1/2,3/2 orderings, the electron correlations, especially the electron correlations owing to the 2p^5 configuration interactions.     

SHELL (DEFORMATION) EFFECT IN NUCLEAR CHARGE RADIUS

It is shown that without exception the observed rms charge radius constants of strongly deformed nuclei, rp's, are a little larger than those of the neighbouring spherical nuclei. The local variations among the charge radii of the sequence of isotopes, the in complete neutron shells [1p_3/2(N~3—6), 1d_5/2(N~9—14), 1f_7/2(N~20—28), 1g_9/2(N~40—50), 1h_11/2(N~70—82)], display some peculiar behaviors (eg. rms cnarge radii decrease with increasing A) which are sharply conflicting with the traditional A^1/3 law. Taking the deformation effect into account, these strange variations can be accounted for with the Z^1/3-law.     

THE VERTICAL INTEGRATED MOMENTUM SPECTRUM OF THE MUON WITH MOMENTUM LARGER THAN 4 GeV/c AT 3220m ABOVE SEA-LEVEL

At an altitude of 3220 meters above sea level in Yunnan Province, we measured, by using a G-M counter-magnetic spectrometer, the vertical integratted momentum spectrum of the cosmic muon with momentum larger than 4 GeV/c. The spectrum obtained from this experiment is expressed by a power function in the form of I（>p）=Q （p+4）^-1.86±0.06(cm^-2·sr^-1·s^-1), where p is in GeV/c and Q is a constant. We also measured the charge ratio of muon in the 4—23 GeV/c momentum range. The result is N_μ/N_μ-=1.26±0.11. The error in the momentum measurement with spectrometer has been discussed and calculated.     

PION CLOUD MIT-BAG MODEL OF HADRON STRUCTURE

We Construct a pion cloud MIT-bag model with chiral symmetry. The pion cloud outside the bag is a classical spherica field. The calculated hadron mass spectra are comparable with the experimental data. The decay width of Δ⁺⁺(1236) calculated in this model is Γ_Δ=115.8 MeV, which is very close to the experimental value. We also calculate the phase shift of P₃₃ resonance. The resultin curve fits the experimental data exceedly well.