Model-independent test of the Adler-Weisberger sum rule for kaons

A test of the Adler-Weisberger sum rule for kaons is performed. To evaluate the integral over the unphysical cut, we use the model-independent results obtained previously by Yndurain and the author. The value of |g_A^Λ| given by the Adler-Weisberger rule assuming positivity for the absorptive part of the elastic amplitude K^?p below the threshold is 0.67 ± 0.06, to be compared with the experimental value 0.66 ± 0.06.     

Search for rare decay modes of Californium

The results ofmeasurements on the search for the cluster decay of ²⁵²Cfnucleus with the emission ofthe bound state of eight neutrons are presented. The value of an upper limit ofthe partial probabilities for this process is obtained, which contradicts to the results ofthe recently published work, in which the possible existence of octaneutron was declared. Based on the results of our measurements, the estimations for the upper limits ofpartial probabilities for the emission of ²⁰C, ²⁴O, ²⁸Ne, 32Mg, ³⁶Si, ⁴⁰S, ⁴⁰P, and ⁴⁰Si clusters are given. The estimation for the upper limit of the partial probability of ²⁵⁰Cf decay with the emission of the bound state of six neutrons is also obtained.     

A nonlinear sum rule for atomic hydrogen

Summary A sum rule for the nonlinear absorption of a probe beam induced by an external light beam is derived for the H atom. Numerical calculations are carried out using the pseudostate summation method and the consistency of the calculation is verified by comparing the length and the velocity gauge. The results confirm the validity of the pseudostate summation method in perturbation theory and give a measure of the strength of nonlinear effects in atomic hydrogen. They are shown to increase by orders of magnitude with increasing the frequency of the external beam. Asymmetries in the nonlinear absorption are expected, with larger negative contributions on the high-frequency side of the spectrum.     

A new sum rule for dense fluids

A new high frequency kinetic sum rule for classical simple fluids is obtained. It involves only the static pair- and triplet-correlation functions; its self part and the local limit depend only on the pair correlation function.     

Semileptonic decay of B-meson into D and the Bjorken sum rule

We study the semileptonic branching fraction of the B-meson into the higher resonance of the charmed meson D^** by using the Bjorken sum rule and the heavy quark effective theory (HQET). This sum rule and the current experiment of the B-meson semileptonic decay into D and D^* predict that the branching ratio D^**lν_l is about 1.7%. This predicted value is larger than the value obtained by various models.     

A new sum rule from the parton model

We present a photoabsorption sum rule, derived in the framework of the parton model. The sum rule agrees with the experimental data.     

A comment on the surface dielectric sum rule

We show that our ?;-sum rule for the electron response function at a surface is not satisfied in the ?-approximation (semi-classical infinite barrier model), and the recent objection to our procedure by Griffin and Harris is shown to be invalid. Although this approximation is useful for many purposes it does not give a correct result for the plasmon contribution to the surface energy, a fact which is directly connected with its failure to satisfy the ?;-sum rule.     

Ikeda sum rule,self-consistency and double-beta decay in the renormalized quasiparticle random phase approximation

The effect of the inclusion of ground-state correlations into the QRPA equation of motion for the two-neutrino double-beta (ββ_2ν) decay is carefully analyzed. The resulting model, called renormalized QRPA (RQRPA), does not collapse near the physical value of the nuclear force strength in the particle-particle channel, as happens with the ordinary QRPA. Still, the ββ_2ν transition amplitude is only slightly less sensitive on this parameter in the RQRPA than that in the plain QRPA. It is argued that this fact reveals once more than the characteristic behavior of the ββ_2ν transition amplitude within the QRPA is not an artifact of the model, but a consequence of the partial restoration of the spin-isospin SU(4) symmetry. It is shown that the price paid for bypassing the collapse in the RQRPA is the violation of the Ikeda sum rule.     

A comment on the electric dipole sum rule for nuclear photoeffect

Gerasimov's argument on the E1 sum rule for nuclear photoeffect is shown not to hold exactly in simple non-relativistic models. The retardation effect does not precisely cancel the contribution of higher multipoles and remaining terms have about the same magnitude as the cancelled ones. They are also found to be of the order of relativistic correction so that the consistent argument on the higher multipole and retardation effects seems to require a relativistic treatment.     

Third-frequency-moment sum rule for electronic multilayers

The authors establish the third-frequency-moment sum rules for the density-density reponse matrix of electronic multilayer structures modeled as an array of N parallel two-dimensional (2D) electron-plasma monolayers. Layer densities and spacings between adjacent layers need not be equal. Contact is made with previously established sum rules for the isolated 2D electron liquid and type-1 infinite superlattices. The case of the equal-density bilayer is considered and its third frequency-moment-sum-rules for the in-phase and out-of-phase inverse dielectric functions are formulated.     

Longitudinal sum rule for the general dielectric function

The sum rule is derived without assuming any translational or point symmetry. Within the self consistent field approximation, for the case of finite translational symmetry, a more direct proof is given.     

A spectator-quark-model for the photoproduction of kaons

A simple model for the photoproduction of kaons off protons with a lambda hyperon in the final state is presented. In a quark model, the interaction is modelled by the pair-creation of the (anti-) strange quarks in the final state which recombine with the three quarks of the proton to form the lambda and kaon. The calculated scattering cross sections for photon energies up toE _ν = 1.9 GeV are compared to experiment. The pair-creation process is found to have a significant contribution to the total cross section.     

A simple approximate sum rule for correlation-state structure in XPS

We adduce a simple approximate relation for the second moment of the correlation-state structure associated with core ionization by high-energy photons and observed in XPS. The relation follows easily on assumption that the removal of a core electron produces an effect on the remaining electrons which can be described by a perturbation potential. A few simple applications are discussed.     

A QCD sum rule study of the light scalar mesons

We examine the interpretation of the light scalar meson nonet as bound states of the scalar diquark and the scalar antidiquark using the QCD sum rule approach. Our results are obtained by means of the operator product expansion (OPE) including operators up to dimension 8. They show no evidence of the coupling of the tetraquark states to the light scalar meson nonet.     

Raman sum rule and the relation to the infrared sum rule in La2-xSrxCuO4

Electronic Raman scattering has no sum rule in no and weak correlation, but the existence of sum rule has been proposed in strong correlation. The present Raman scattering disclosed that the first moment of the Raman susceptibility is proportional to the generalized moment of the optical conductivity in the metallic phase. The present experiment disclosed that a large amount of electronic states are incoherent states. The incoherent states are the relevant states for the superconductivity, because the gap opens in the incoherent states as well as the coherent states.     

Spin-dependent sum rule for high-energy neutrino reactions

We present a sum rule which related the inclusive cross section for high-energy neutrino scattering on polarized proton targets to the axial-vector coupling constant. The derivation of the sum rule rests on the equal-time algebra of the time-components of the weak currents. The sum rule also provides a discriminatory test of unified models of weak and electromagnetic interactions based on spontaneously-broken gauge symmetry.