1992 Vol. 16, No. 3
Display Method: |
The method of identification of primary cosmic ray particles of gamma families with visible energies above 800TeV has been investigated by using the results of Monte Carlo simulation.It has been found that,for proton primaries.the lateral distributions of certain parameters of gamma families may be taken as a reliable criterion.The experimental data of big gamma families obtained from Mt.Kanbala emulsion chamber experiment have been analyzed on the basis of this criterion.
We state a fitting method of the Z0 line shape.We discuss the radiative corrections for calculating the theoretical cross sections of e+e－→ff on Z0 resonance,and compare the results from different programs.The systematic measurement errors are taken into account in our fitting.As an example,we fit the τ+τ－ channel Z0 line shape to determine some Z0 parameters.
In this paper it is shown that the topologically additional action appearing in the Heisenberg spin model can be understood as a superposition of Berry's phases for the single spins in an average fields of many particles.In the case of low temperature,using the high order adiabatic approximation method,we obtain higher order corrections for this action.
In this paper one problem in H.Georgi's "MOOSE" model is discussed,and the necessity of 't Hooft anomaly matching condition for the confining phase theoretical analysis in Ri/j≈0 region is proven.
The functional formalism for the effective potential is briefly reviewed for the case of a scalar field theory by using the method of steepest descents.This formalism is then applied to quantum electrodynamics and an integral expression is derived for the effective potential in the one-loop approximation.This expression is used to verify the absence of spontaneous symmetry breakdown for quantum electrodynamics in one space and one time dimension.
The helicity formalism of the angular distribution for the cascade decay process e++e－→J/ψ→V+X,X→P1+Y,Y→P2+P3 (V represents a vector meson and Pi(i=1,2,3) are the pseudoscalar mesons) is presented in this paper.It provides the theoretical formulas for the spin-parity analysis of the intermediate state X through a three-step two-body hadronic decay processes of J/ψ.
The α-particle model for 16O is tested by means of the proton scattering.The elastic angular distributions for the proton-16O scattering ranging over the whole intermediate energy region are calculated without any adjustable parameter.A overall agreement between the theoretical results and experimental data is obtained.
The two different normalization schemes of factorial moments are alalyzed carefully.It is found that in both the cases of fixed multiplicity and of intermittency independent of multiplicity,the intermittency indexes obtained from these two normalization schemes are equal to each other.In the case of non-fixed multiplicity and intermittency depending on multiplicity,the formulae expressing the intermittency indexes from the two different normalization schemes in terms of the dynamical index are given.The experimentally observed dependency of intermittency degree on transverse momentum cut is fully recovered by means of the assumption that intermittency degree depends on average transverse momentum per event.It confirms importance of the dependency of intermittency on average momentum.
A confinement potential which obtained from the lattice-gauge-theory has been used to study the spectrum of baryon and the rms of the quark distribution.
The coincidence between projectile-like fragments and α-particles emitted from 20Ne(14.7,19.2MeV/u)+58Ni reactions has been studied.The coincident events were caused by the sequential decay of the excited primary fragments and by the "uncorrelated" coincidence between forward emitted α-particles and projectile-like fragments,formed in a deeply dessipated reaction process,as well.This reaction process means,that the α-particle flied off from the 20Ne projectile in the initial stage of the reaction,and then the residual 16O collides with the target nucleus dissipatively.It is called "Incomplete Deep Inelastic Process".
By using the generator coordinate method approach to the dynamic group represenation (DGR-GCM),the continuous variables representation of IBM is obtained under the low excitation approximation and is compared with BMM.Not only the relation between the mean field and the dynamical symmetry has been analysed but the spherical nuclei as well as deformed nuclei have been discussed in an unified way.The accuracy and available extent of the continuous variables representation is demonstrated by means of analysing the potential surface and the spectra of Gd isotopes.The results have been compared with the experimental data and the algebraic solution of IBM (PHINT CODE).
The accurate solutions to the low-lying eigenstates of the cranked shell model Hamiltonian are obtained by the particlenumber-conserving treatment,in which Coriolis attenuation is considered.Compared with experiments,the results are much better than before.
By the intrinsic condensate method,an attemption is made to cancel the maximum F-spintruncation approximation usually adopted in IBM2.In the region of deformed nuclei,the intrinsic condensate and is intrinsic excitations are used to describe the low-lying collective rotational states.Using this method.the low-luing spectrum of 168Er are calculated.The result show that the maximum F-spin truncation approximation become bad for the excitational bands,and the intrinsic excitations of neutron boson and proton boson are mutual separated.
Using the group theoretical method,the wavefunctions of intrinsic states for the strong coupling SU(3) limit in IBM4 are given.Then,the wavefunctions of ground states band are obtaind from the above wavefunctions by a projection method.
This paper studies a mechanism of acceleration of high-energy nucleons in intermediate and high energy nucleus-nucleus collisions,where a part of the projectile nucleons undergo alternating shuttle collisions between the target and the rest of the projectile,and successive accelerations.Preliminary calculations based upon a classical picture indicate that an energy boost of 0.33E0 can be generated after once shuttle collision,E0 is the mean incident energy per nucleon.The energy spectra and angular distributions of emitted nucleons are evaluated,and the physical significances of the results are discussed.
- A SCOAP3 participating journal - free Open Access publication for qualifying articles
- Average 24 days to first decision
- Fast-track publication for selected articles
- Subscriptions at over 3000 institutions worldwide
- Free English editing on all accepted articles
- The 2023 Chinese New Year-Office closure
- 2022 National holiday- office closure
- The 2022 summer holiday-Office closure
- Impact factor of Chinese Physics C is 2.944 in 2021
- The 2022 Labor Day Holiday-Office closure