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In order to apply gold nanoparticles to the materials for electronic and optical devices, they are required to be tolerant of heat applied in the fabrication processes. In our previous study, novel gold nanoparticles with excellent thermal stability were developed by introducing an amide bond and a condensed ring into the ligand molecules. On the other hand, particle size is a key factor in determining device performance, gaining control over the size is highly advantageous. In this study, a size-increase reaction of the pyrene-containing gold nanoparticle was carried out. The particle size was successfully increased from 2 to ca. 10 nm, without lowering the thermal stability. Furthermore, their interligand interactions could be probed using fluorescence measurements based on the characteristic excimer emission of pyrene. It is suggested that strong p–p stacking occurred around the particles, even after the size-increase reaction, contributing to maintaining the thermal stability.

AbstractPoly-(γ-benzyl-L-glutamate) molecules have been bonded covalently to a flat substrate viacarbonyl end group to form an aligned dipole layer (CRA film). The authors have evaluated the electric influence of the CRA film on the dynamic change of the hydrogen-bonded liquid crystalline complex of 4-hexyloxybenzoic acid and 4-nonylpyridine (6OBA-9Py) by means of time-resolved infrared spectroscopy. Using the CRA film as an orienting film for 6OBA-9Py, the absorbance change of the complex when burst electric field was applied had many steps in response to the change of its sign. Moreover, the movement of the 6OBA-9Py complex was induced by an external electric field, not only in the direction of the complex long axis but also in that of the complex short axis. This characteristic dynamic behavior of the 6OBA-9Py complex was due to the weak hydrogen bonding.

Conducting poly(pyrrole) composite films were prepared by chemical polymerization in oxidant solutions by dipping poly(ethylene terephthalate) film (PET film) coated with poly(methyl methacrylate) (PMMA) and pyrrole monomers into a FeCl3aqueous solution. The oxidation potential of this solution was controlled by adding a suitbable amount of FeCl2to the solution before the reaction. By selecting appropriate polymerization conditions such as oxidation potential, temperature, time and FeCl3concentration, highly conducting poly(pyrrole) composite films could be obtained. The SEM studies of the synthesized films indicated that polymerization conditions which lead to high reaction rates often yielded films of aggregated structures which have low conductivities.

The reaction of lithocholic acid with silane coupling agent on a Si crystal surface was analyzed with FT-IR(ATR), XPS, and contact angle. The generation of amide bonds within 1nm of the Si surface was confirmed with XPS. The yield of amide was 84%. An abnormal IR absorption was observed in the amide band region.

We revisit the EPR problem and make clear what is a correct comprehension of its problem. When one applies the quantum mechanics correctly, it will be shown that there is no paradox. According to these lines of thought, a quantum teleportation scheme without resort to the von Neumann projection postulate is presented.

Selectively monoprotected unsymmetrical 1,3-diketones were obtained by the reaction of 2,2-dimethoxyethyl esters with enamines in the presence of dichlorobis(trifiuoro-methanesulfonato)titanium.

An efficient and highly diastereoselective Michael addition of enamines with 2,2-dimethoxyethyl esters of α,β-unsaturated acids was achieved by using titanium(IV) chloride as an activator.

Three types of novel gold nanoparticles containing a different condensed ring in their ligands were prepared. Their thermal stability was found to be much higher than that of typical gold nanoparticles surrounded by long-chain alkanethiols because of strong interligand interaction formed by the condensed rings (π–π stacking). A clear correlation was found between the thermal stability and the strength of π–π stacking.

The physical gelation of isotactic polypropylene in naphthenic oil was drastically enhanced by adding a small amount of ceramic fibers after modification of polypropylene with maleic anhydrate. The micrograph of the gel showed the network of ceramic fibers crosslinked with polypropylene crystals formed by nucleation at the surface of the fibers.

Within the framework of the composite particle model, some meson-nucleon large angle scatterings at high energies are qualitatively discussed as the rearrangement collision among constituent particles of meson and nucleon. The purpose is to see the dynamical structure of elementary particles whose characters are clarified only by the fashionable symmetry argument. In this note the two types of models with the same symmetry are investigated: (i) the “atom-type” of models in which all mesons and baryons are, in the same level, composed of a small number of urbaryons, and (ii) the “molecule-type” of models in which only (all or some) baryons are composed of urbaryons but the other particles (mainly mesons) are composed of the baryons. The backward peaks in the angular distribution of meson-nucleon scatterings may be understood as the exchnge effect, since the scatterings are analogous to the deuteron-proton scattering in the “molecule-type” of models and to the deuteron-triton scattering in the “atom-type” of model. From this point of view, the two sets of predictions are, correspondingly to the above two types of model, obtained about appearance of the exchange backward peaks in various meson-nucleon scatterings at high energies. The existing experiments on π±p→π±p at 4 GeV and 8 GeV seem to prefer the “molecule-type” of models. Finally discussion are given on the energy dependence of the exchange backward peak and on the related hard core problem.

An attempt is given, which aims at representing the fundamental laws of weak interactions as conservation laws instead of conventional violation laws. We assume that the conserved quantities characteristic to weak interactions are anti-commutable with those characteristic to strong interactions. All weak interactions are assumed to occur via intermediate boson, which is assumed to belong to an eigenstate of the conserved quantity for weak interactions. V - A law is derived in this way by adoptin the chirality as one of the conserved quantities. We adopt also as an conserved quantity the iso-chirality which is defined tobe an operator anti-commutable with the iso-parity. Then isospin and hypercharge are not conserved, and |ΔI| = 1/2 rule is derived using weak current composed of bilinear forms of quarks. The Cabibbo angle appears natrally in the general definition of the iso-chirality operator. Also briefly discussed is a possible scheme of leptonic interaction, which satisfies the three conditions; |ΔI | = 1/2 rule for hadronic processes, nonn-appearance of neutral lepton currents and universality of coupling constants in the primary interaction between intermediate bosons and weak currents.

As described in Part I, Taketani, Nakamura, and Sasaki proposed that the outer region of the nuclear potential can be treated substantialistically and the inner region phenomenologically, and much progress has been done since the proposal. In the present Part III we shall, therefore, show how the region where the nuclear potential derived from the present pion theory is reliable has been established.

It is shown that the Bethe-Salpeter equation with the interaction kernel determined by the dual realistic quark model do not have the solutions of scalar and axial vector types with respect to spinor indices. The reason why only the pseudoscalar and vector type solutions exist is clarified. It is concluded, therefore, that our theory allows only the SU(6)-type solutions for one-meson states at rest. Our interaction kernel prohibits naturally quarks from appearing as free particle in the incoming and outgoing states. Normalization of the solutions is discussed. Our theory becomes much simpler by taking the mass of the quark to be infinity at the last stage of calculation, the remaining parameters being the coupling constant, slope and zero intercept of the leading orbital Regge trajectory. It is suggested that this limit may have some connections with the dual string model where end points of the string are interpreted to be the valence quark and antiquark which carry the degrees of freedom of unitary spin, spin and spatial coordinates.

The Bethe-Salpeter equations for baryons are solved in the relativistic quark model. The dual interaction kernel is used. Spatial parts of the Bethe-Salpeter amplitudes are given by the factorized residues at poles of the interaction kernel. By introducing eigenvalues of integration kernels all possible spinor forms are shown to five solutions. Physicality conditions for eigenvalues and their energy-derivatives at resonance points play a very important role to discriminate these solutions: Spinor wave functions which appear in SU(6) theory satisfy the physicality conditions and others do not. Our theory explains, therefore, SU(6)⊗O(3)L symmetry as a dynamical consequence of the relativistic composite theory.

General forms of the Bethe-Salpeter amplitudes for a baryon are given in the relativistic quark model. Internal angular variables are defined so as to make mixed representations disappear. Spinor functions are given by γ-matrices parallel or orthogonal to four-momentum of the baryon. These functions are eigenstates of spin and parity, have simple physical meanings and are very convenient for many purposes.

Dual composite theory of many-meson amplitudes is applied to investigation of the Bethe-Salpeter (BS) equation for one-meson states. The interaction kernel is the direct extension to this case of those which were determined by duality for many-meson amplitudes. The BS equation is shown to have solutions with the following properties: i) There are no second-kind exotic states in the leading Regge trajectories. ii) Mesons form approximate irreducible representations of SU(6) ⊗O(3)L and SU(6)W ⊗O(2)Lz symmetry at rest and for linearly moving states respectively. iii) These states may be made exact irreducible representations if one takes an appropriate form of an arbitrary function of total momentum which remains in the BS amplitudes. iv) Mesons form linearly rising Regge trajectories with respect to the total orbital angular momentum of urbaryons inside the meson. v) Dependence on relative space-time coordinates of the BS amplitudes is given by the factorized residue functions at the poles of the dual function in the interaction kernel. vi) BS amplitudes on the leading trajectory have positive norm, whereas there appear negative norm states also on the daughter trajectories when the Veneziano function is chosen as the space-time part of the interaction kernel. Discussion is given on the relations among the constructive and interactive forces and on the duality in the composite theory of hadrons.

General scope and general formulation of the theory of quantum-mechanical measurement are given. Essential points of our theory are that macroscopic apparatus is associated with many Hilbert spaces and the dynamical scattering theory is applied to microscopic interactions between object and apparatus. It is shown that our theory gets over the Furry-Wigner-Fine criticisms.

New theory of measurement is presented to show that quantum mechanics can describe the whole processes of quantum-mechanical measurement leading to the so-called reduction of wave packet if applied properly to the total system of object and apparatus. We introduce a simple model, where momenta of particles are measured using a perfect rigid mirror, to yield the reduction of wave packet in a clear-cut way. Microscopic uncertainties of macroscopic quantities and the dynamical scattering theory play the essential roles. Before entering into the main part, we briefly summarize the controversial points in the theory of measurement.

Spectral representations of the electromagnetic form factors of the nucleon for fixed momentum transfer are proved as a function of the square of the four-momentum of the nucleon, based on the general principles of the quantum field theory and, using these representations, two sets of coupled equations for charge and magnetic moment form factors are derived. These equations are solved in an approximation in which only the lowest mass configuration is taken into account which consists of one pion and one nucleon. It is shown that the absorptive parts in this approximation are expressed in terms of the real pion production by virtual photon for I = J = ½ state and pion-nucleon vertex part, from which follows that (3-3) resonant state does not contribute to the form factors as far as the lowest mass configuration is concerned. Inclusion of (3-3) resonance and the second and third resonance requires the calculation of two pions and one nucleon state which is not attempted here.

Several fundamental problems on a two-nucleon system in the momentum space are discussed with the view that they will be useful for treating the two-nucleon problem completely nonstatically, i. e. without making use of the expansion in terms of the inverse of the mass of the nucleon. General forms for a two-nucleon potential in the momentum space are derived, and the integral equations which are the Fourier transform of the Schrödinger equation and their solutions are briefly discussed. Formulas for matrix elements of the most general types of potentials are evaluated and are applied to the nonstatic one-pion-exchange potential.

A list of the nonstatic one-boson-exchange potentials between two nucleons is given. The potentials are obtained exactly in the momentum space. In the coordinate space they are given up to the order M-2 in the M-1 expansion. (M is the nucleon mass.)

Under the assumption that the baryon is composed of three subnuclear particles in a nonrelativistic bound state analogous to the nuclear structure, the possible inner symmetries of the baryon structure are discussed by comparing with some characteristic features of the leptonic decays, such as n → p and Λ→ p. First, under the charge independence, the characteristic parameters of the neutronβ decay are expressed in terms of the nucleon structure constants. By comparing the parameters with experiments, it is concluded that the totally symmetric spin-unitary spin part is dominant in the nucleon structure. This is true in the baryon structures in the SU3 symmetric case. Under the SU3 invariance, the following relation between theβ decays of neutron and Λ particle is also derived: (GA/GV)Λ→ p = (1/2) × (GA/GV)n → p -1/6 ≃ -0.76, where (GA/GV)n → p ≃ -1.185 is used. The broken SU3 symmetry is estimated by making use of the existing experiments on theβ decay of Λ particle. Finally the decay rates for various leptonic decays are obtained from the theoretical values, F ≃ 0.55 and D ≃ 0.65, determined by the experimental value of (GA/GV)n → p in the SU3 symmetry case of the present theory. The results are consistent with the experiments.

Relation between the composite models and the Regge behaviors of the hadrons are discussed. Composite particles are expected to show Regge behaviors owing to the smoothness of the dependence on angular momentum of the “force” acting between the constituent particles. π-p charge exchange scattering with the ρ-trajectory is analyzed explicitly. Taking the quark model as an example we Reggeize the crossed channel quark-antiquark scattering amplitude by the use of the additivity assumption and the crossing relation between the direct channel quark-quark or quark-antiquark amplitudes and the crossed channel amplitudes. Calculated results are insensitive to the mass of the quark, and the trajectory agrees with experimental values for |t|\lesssim1 (GeV/c)2. The residue of the ρ-trajectory appearing in the S-matrices for quark-quark and quark-antiquark scattering, b(t), varies slowly with t. The residue in the S-matrix for π-p charge exchange scattering is obtained by multiplying b(t) by the form factors of the composite hadrons, and it turns out that the resulting residue function has an exponential dependence on t, which is required to fit the experimental data. The magnitude of the exponent agrees very well with the one determined by other experimental data. It is conjectured that the residue function of the Regge poles appearing in the S-matrix for hadron-hadron scattering reflects the compositeness of the hadrons directly and is determined by the spatial extension of the wave function of the constituent particles in the hadrons.

Recently a general and formal method to construct nuclear potentials has been proposed by Fukuda, Sawada and Taketani. Applying the method to the pion theory and adopting fixed and extended sources, we have evaluated nuclear potentials. The result seems to be in favour of that of Taketani, Machida and Onuma rather than that of Prueckner and Watson. As a cut-off function we assumed a Gaussian error function with kmax=6µc. In the case of the effective coupling constant g2/4π=0.08 it is found that the effect of the extended source becomes very strong in the region for r≪0.7 \hbar/µc. If we use these potentials for r>0.7 \hbar/µc and phenomenological potentials inside this range, satisfactory results may be obtained to explain the properties of the two nucleon system in the low energy region.

Theory of the reactions of hadrons, assumed to be composed of urbaryons with the degree of freedom of the spatial motion as well as those of unitary spin and spin, is discussed. An integral equation is derived for the one-time Bethe-Salpeter (BS) amplitude, based on the observation that the knowledge of the BS amplitude with the same value of time variables for all constituent particles is sufficient to derive the S-matrix element and by introducing the modified interaction kernel. The equation is a Klein-Gordon type integral equation in the momentum space, whose interaction kernel is energy-dependent and nonlocal and is also shown to be complex normal in general. Dispersion relations for that kernel and properties of their eigenvalues are also discussed. Resonances are discussed on the basis of the expansion of the kernel and the resolvent by the eigenvalues and the eigenfunctions of the kernel. The S-matrix element is shown to obey a difference equation approximately. By generalizing this difference equation so as to satisfy the crossing symmetry and by solving the resulting simultaneous difference equations with a suitably chosen form of the eigenvalues, we obtain a generalization of the Veneziano or the Virasoro amplitude. The original Veneziano or Virasoro amplitude is obtained as a limit of the above function which corresponds to the case of the eigenvalues of the kernel being a linear function of the square of the total energy in the center-of-mass system.

We evaluate the real and imaginary parts of the partial wave phase shifts for elastic pp, π±p and pp scattering from the experimental data on the total cross section, differential cross section and the ratio of the real to the imaginary part of the forward scattering amplitude, assuming no spin dependence. In the case of pp scattering the calculated values of the ratio of the real to the imaginary part of the forward scattering amplitude are used, because there are no experimental data available. The results obtained depend mainly on the contribution of the diffraction scattering, and it is shown that the contributions from the intermediate and large angle scattering are quite small numerically. It is also shown, by examining several reasonable forms of the t dependence of the ratio of the real to the imaginary part of the scattering amplitude, that it does not affect the results appreciably. The results obtained are the following. The real parts of the partial wave phase shifts are, in all cases, negative and the absolute values decrease proportionally to (ln s)−1 for pL ≳ 10 GeV/c, up to an additive constant which is an integral multiple of π, where pL is the momentum of the incoming particle in the laboratory system. This additive constant is considered to be zero in the case of pp scattering according to the generalized Levinson's theorem. The reflection coefficients expressed as a function of the impact parameter indicate the occurrence of strong central absorption in the region where the impact parameter is nearly equal to or smaller than the nucleon Compton wave length for pL ≳ 10 GeV/c, in contrast to the case for pL ≳ 4 GeV/c where only peripheral absorption occurs. Therefore the real and imaginary parts of the scattering phase shifts obtained in thie way suggest the existence of a certain critical energy in the region 5 ≲ pL ≲ 10 GeV/c, where their qualitative behavior changes drastically. The existence of a critical energy of this kind is in agreement with the results expected on the theory where a “central part” composed of many fermions is assumed to exist with a radius of the order of the nucleon Compton wave length.

It is shown by a general argument that the one pion exchange potential is not changed but the unrenormalized coupling constant must be replaced by the renormalized one, in the region far from the origin, where the static approximation is allowed, by the inclusion of the radiative effects. It is found in the analysis of two nucleon problems that the one pion exchange potential given in the meson theory of nuclear forces plays the main role in the low energy region and gives excellent agreements with experiments.

The electric and magnetic form factors of nucleons are treated on the basis of the model in which the nucleon has a “central part” with spin one half, which is composed of three urbaryons (like quarks) and whose extent is of the order of magnitude of the nucleon Compton wave length. These quarks need not have a “particle-nature” in all respects, but may be some sort of quasi-particles. In the case where the quarks are fermions or parafermions, the general forms of the nonrelativistic wave functions of the three-body systems are given and the Fourier representations of the completely symmetric or anti-symmetric space wave functions are obtained in order to get the electric and magnetic form factors coming from the “central part”. The effects of the boson cloud are taken into account as the contribution from boson resonances. It has become clear that the electric form factor of proton evaluated only from the boson resonances does not agree with the recent experimental data. It is shown that if the contribution of the “central part” is taken into account, the agreement of the theoretical form factors with experiment is much improved. Although this does not necessarily establish the existence of the “central part”, it indicates at least that our model is consistent with the experimental data. The existence of the “central part” not only gives the electric and magnetic form factors by itself, but also, as the source of bosons, explains the effective masses of the boson resonances, which are smaller than the real masses required by the experimental data. If the radius of the “central” part is assumed to be much smaller than the order of magnitude of the nucleon Compton wave length, for example one-tenth of it, it is hard to get agreement with the present experimental data. In addition to this, if the absorption effect is taken into account, in the case of peripheral approximation, the assumed order of magnitude of the radius of the “central” part seems to be consistent with experiment. The existence of the “central part” suppresses the processes with impact parameter smaller than the nucleon Compton wave length. Further, since the many-particle exchange processes at relatively low energies are suppressed more severely as the number of exchanged particles increases, as a result of the existence of the “central part”, this gives one of the reasons for the apparent partial success of the peripheral approximation.

Spin-, unitary spin-, and momentum-dependences of N-point meson amplitudes are obtained, using the “realistic quark model” in which the quarks are assumed to have the following properties; definite unitary spin, spin, coordinate and statistics. Furthermore we assume cyclic symmetry of hadron external lines and factorization at the hadron poles, which leads us to the same unitary spin dependence as in the case of the “mathematical quark model” in which the quarks are only considered as a mathematical symbol. As for the spin dependence, however, serious differences to appear; many of the difficulties of the mathematical quark model are removed and in the case of π-π scattering, the factor from the high energy behavior is naturally derived from our spin factor. We also offer a reasonable form of “the spatial part” of the scattering amplitude, assuming a certain symmetry at the quark level.

In this paper hadrons are assumed to be composed of urbaryons which obey definite statistics. The exclusion principle, acting between pairs of urbaryons or antiurbaryons contained in the different hadrons in the s-, t- and u-channel, gives definite contributions to reaction amplitudes for hadronic processes (which may be called the “super exclusion principle”). Calculations are performed, assuming that the urbaryons are represented by a local field with the Fermi-Dirac statistics for definiteness. Effects of the super exclusion principle are expressed, in the short range approximation discussed in §2, by the original amplitude smoothed by the convolution with the Fourier transform of the internal wave function of the hadron. Effects depend critically on the number of urbaryons and anti-urbaryons contained in the hadrons: and are shown generally to appear in the low partial waves at low energies. The largest effect appears in the S-state with the sign inverse to the original S-wave amplitude. By using the Veneziano amplitude as the original amplitude, it is shown that the effects of the super exclusion principle damp very rapidly at high energies. An exception is the case of meson-meson scattering where the effects have the same energy dependence as the original amplitude. Therefore we expect the existence of the low partical wave (or S-wave) anomaly for most hadronic processes. This anomaly seems to exist actually for KN, πN and NN scattering, and is considered to be the strong support for the composite theory of hadrons. Comparison of the effects of the super exclusion principle with experimental data are made semi-quantitatively for KN, KN, πN and NN scatterings. Unitary spin is considered in §5, and it is shown that the deviation from the Okubo-Iizuka rule is small for the strong decay of a meson into two mesons. Analytic properties of the contribution of the super exclusion principle are also investigated. It is shown that they give an imaginary part for exotic channels as well as for nonexotic channels and destroy duality.

A method is presented for analyzing data on nucleon-nucleon scattering in the energy region where absorption processes cannot be neglected. The imaginary parts of the phase shifts are estimated from data on pion production with the use of the (3/2, 3/2) resonance model. Secondly the scattering data are analyzed to obtain real phase shifts. The search is made for real phase shifts in the phase shift space which is restricted by extrapolating the solution established below about 400 Mev. An analysis is made, according to this scheme, for p-p scattering at 660 Mev, and the following results are obtained. 1) The absorption occurs mainly in the initial P, D and F states. ii) Data on elastic differential cross section, polarization and depolarization can be reproduced by a set of phase shifts which is smoothly connected with the solution of the Stapp No. 1 type below about 400 Mev. The Cnn(90°) and CKP(90°) values recently measured are also consistent with those predicted by the solution obtained. (iii) An example of solutions is as follows: where r = exp (−2δI), δI being the imaginary parts of the phase shifts, and phase shifts are nuclear-bar phase shifts.

A study is made of polarization effects in high-energy scattering. Consideration in the limiting case of complete absorption or of the absence of real phase shifts leads to the possibility of obtaining information on two-baryon elastic interactions from polarization experiments at high energies. An approach to two-baryon interactions at close distance is briefly described.

A systematic theory of weak interactions is presented on the assumption that the primary weak interaction is the one between the intermediate boson and the weak currents. Assuming that the regularities of asymmetry parameters of hyperon nonleptonic decays reflect a certain fundamental law, we consider the doublet spin to be of primary importance. Properties of currents assumed in the present work are the following: Vectorpart of the strangeness conserving current is conserved; there exist two kinds of strangeness violating currents, scalar and vector in the doublet spin space respectively, and both of them are of γµ-type, i. e. do not include γµγ5-type interaction. It is assumed that the primary weak intereactions conserve the doublet spin, the K-spin and the strangeness. Main conclusions of our theory are the following: (a) There exist two sets of intermediate bosons, each set consisting of the particles with +, − and 0 charges and their antiparticles (different from particles); (b) intermediate bosons have dual properties, like schizon, concerning the doublet spin, the K-spin and the strangeness; (c) transitions with |ΔS| ≧ 2 do not occur in the first order of weak interactions; (d) isospin selection rule, |ΔT| = 1/2, does hold for nonleptonic decays. Asymmetry parameters have the following regularities: α (Σ+ → n + π+) = 0, α (Σ+ → n + π+) = 0, α (Σ− → n + π−) = 0, α (Σ+ → p + π0) = −α (Λ → p + π−) = α (Ξ− → Λ + π−) ; (e) |ΔT| = 1/2 does not hold for leptonic decays of hyperons and kaons, and both of processes with ΔS = ±ΔQ occur; (f) matrix elements for K0 → l+ + νl + π− and for K0 → l− + νl + π+ are identical. K20 → l± ± νl + π∓ and K0 → l+ + νl + π0 occur via corrections to the doublet approximation, and the order of magnitude of the ratios of the decay rates of these processes to that of K10 → l± ± νl + π∓ are expected to be (g) if we assume the universality of coupling constants of the primary interactions, leptonic decay rates of hyperons become approximately 1/8 for Λ and 1/16 for Σ, respectively, of those calculated from the universal V - A four fermion interaction. In this case, occur with the same probability; (h) the Ξ-nucleon parity has to be odd; (i) the parity is conserved in the baryon-baryon scatterings with ΔS = 0 even when the first order weak interactions are included. An apparent violation or conservation, in the weak interaction processes, of the doublet spin, the K-spin and the strangeness are regarded in our theory to be the manifestation of the dual natures of the intermediate bosons concerning the corresponding quantities.

Effects of virtual nucleon pairs to the electromagnetic structure of the nucleon are calculated covariantly in the charge independent pseudoscalar meson theory. A rigorous expression for the vertex operator is derived in §2, which is strongly reminiscent of the old-fashioned first- and second-order perturbation theory. Our method of approximation is to replace the complete set of eigenfunctions of the total Hamiltonian by some suitable functions, which are chosen in this paper so as to take into account the main contribution from the virtual nucleon pairs. These effects are proved, regardless of the magnitude of the coupling constant, to reveal itself only through the renormalization factors, which affect the relative magnitudes of the isotopic scalar and vector parts of the nucleon-current contributions and the meson-current contributions. Numerical results are almost the same with those obtained by cutting off the momentum integration at the nucleon mass in the second order perturbation calculation both for the ratio of the anomalous magnetic moments of the proton and the neutron and the mean-square radii of the charge distributions.

Nonstatic nuclear potential due to one-pion-exchange process is derived in the momentum space without using the expansion with respect to the inverse of the mass of the nucleon. Close examinations of its properties show that it can be expressed with good accuracy by a local potential in x-space at low energies (below nearly 300 Mev). Nonstatic parts of the potential have different signs accordings as whether the assumed coupling between the pion and the nucleon is pseudoscalar or pseudovector. Comparison with the experimental phase shifts is briefly discussed. It is shown in the case of the pseudoscalar coupling that the nonstatic one-pion-exchange potential derived in this paper is almost exact from the theoretical point of view when the distance between two nucleons is far enough (large compared with one third of the pion Compton wavelength). It is also argued on some physical assumptions that the potential will in fact be exact in the case of the pseudovector coupling too.

The method of the theory of the nuclear forces proposed by Taketani, Nakamura and Sasaki is developed to clarify the present stage of the theory of the nuclear forces and to discuss the aims, as well as the important results obtained up to present, of the theoretical investigations which are now in progress by our group.

General types of the mesonic correction to the β-decay are obtained from the invariance requirements. Explicit calculations are performed, using Feynman-Dyson method, up to the second order of meson-nucleon coupling constants for the synmetrical pseudoscalar meson theory with both pseudoscalar and pseudovector couplings. It is shown that the mesonic correction is small and does not affect the selection rules and spectra in the Konopinski's forbidden theory.

We discuss on the validity and approximation method of the adiabatic nuclear potentials, especially of the fourth order nuclear potential derived from pseudoscalar meson theory. In §2, it is shown that effects of time component of pseudovector coupling on the pseudoscalar meson potential are not large when distance between two nucleons is larger than about half of the force range. In §3, time variation of nucleon spin and τ-spin are evaluated for phenomenological and meson potentials, and critical radii for their applicability are derived. In §4, implications of the velocity-dependent forces in the interior region are discussed, and largeness of the purely quantum mechanical effects in the meson theory is pointed out. Hamiltonian for a two nucleon system in the intermediate coupling approximation is given. In §5, features of the meson-nucleon interaction are compared with that of the photon-electron interaction. It is pointed out that the transition matrix of the nucleon-nucleon collision is not analytic with respect to nucleon energy at the threshold for meson production. An ambiguity occurs when one intend to calculate the sixth order nuclear potential.

Adopting the new method of the theory of nuclear forces proposed by one of us (M.T) and others, the deuteron ground state and low energy neutron-proton scattering have been investigated. The symmetrical pseudoscalar π-meson potentials including second- and fourth-order terms are assumed in the outside region, while in the inside region where the static meson potential becomes meaningless, phenomenological potentials represented by square well are adopted. It is shown that we can then account for the experimental data, if we take the value 0.09 ∼ 0.10 as the magnitude of the coupling constant between π-meson and nucleon. Saturation does not result from these potentials in the static approximation.

In this paper hadrons are assumed to be composed of urbaryons which obey definite statistics. The exclusion principle, acting between pairs of urbaryons or antiurbaryons contained in the different hadrons in the s-, t- and u-channel, gives definite contributions to reaction amplitudes for hadronic processes (which may be called the “super exclusion principle”). Calculations are performed, assuming that the urbaryons are represented by a local field with the Fermi-Dirac statistics for definiteness. Effects of the super exclusion principle are expressed, in the short range approximation discussed in §2, by the original amplitude smoothed by the convolution with the Fourier transform of the internal wave function of the hadron. Effects depend critically on the number of urbaryons and anti-urbaryons contained in the hadrons: and are shown generally to appear in the low partial waves at low energies. The largest effect appears in the S-state with the sign inverse to the original S-wave amplitude. By using the Veneziano amplitude as the original amplitude, it is shown that the effects of the super exclusion principle damp very rapidly at high energies. An exception is the case of meson-meson scattering where the effects have the same energy dependence as the original amplitude. Therefore we expect the existence of the low partical wave (or S-wave) anomaly for most hadronic processes. This anomaly seems to exist actually for KN, πN and NN scattering, and is considered to be the strong support for the composite theory of hadrons. Comparison of the effects of the super exclusion principle with experimental data are made semi-quantitatively for KN, KN, πN and NN scatterings. Unitary spin is considered in §5, and it is shown that the deviation from the Okubo-Iizuka rule is small for the strong decay of a meson into two mesons. Analytic properties of the contribution of the super exclusion principle are also investigated. It is shown that they give an imaginary part for exotic channels as well as for nonexotic channels and destroy duality.

The one-pion-exchange contribution to the Λ-N interaction is investigated. This is expected to be appropriate for investigation of the violation of the charge independence in the strong interaction, because this contribution has a long force range, which is twice as large as that of the charge independent interaction, and moreover has an unambiguous functional form, the strength of which is of equal magnitude and of opposite sign for the Λp and Λn interactions. Effects of this interaction on the scattering lengths and effective ranges for singlet and triplet S states are evaluated for typical values of the parameters. Results are given in Eq. (7·5).

It is shown that the pattern of Regge trajectories of hadrons becomes very much simpler and more regular than the usual Chew-Frautschi plot when one uses the orbital angular momentum of the quarks in a hadron instead of the spin of the meson and the spin minus 1/2 of the baryon, as the Reggeized angular momentum. Available data on particles and resonances are classified by means of the quark-orbital Regge trajectories, and as a result of it, the following pattern appears: there are linear rising quark-orbital trajectories with the universal slope for each irreducible representation of SU(6); actual hadron spectra are reproduced by adding the spin- and unitary spin-exchange interactions and the mass shift of the λ-quark. The Gell-Mann-Okubo mass formula holds rather good including resonances with high mass. Effects of the spin-orbit interaction are clearly recognized and its magnitude is nearly of the same order as those of the spin- and unitary spin-exchange interactions for mesons, whereas they are not so obvious for baryons. It follows from this splitting pattern of the quark-orbital Regge trajectories that the exchange degeneracies hold better for mesons than for baryons and that many “parity doublets” exist apparently and several parity partners should not appear, in conformity with experimental data. Classification of resonances using the orbital angular momentum between incoming two hadrons does not show much regularity. It is suggest from these results that strong interactions are essentially characterized by the degree of freedom of the spatial motion at the urbaryon level.

The statistical potential moel for high energy elastic scattering is proposed in order to account for large angle scattering in a unified framework describing the real part of the forward elastic scattering amplitude. The whole amplitude is considered to be decomposed into two parts: one is the pure imaginary shadow scattering amplitude and the other the statistical potential scattering amplitude. The statistical potential scattering amplitude T(c) is formulated under the assumption that many scattering centers are produced when the central collision occurs, and that the distribution of these scattering centers is determined by a distribution function subject to some statistical law. The amplitude T(c) can be treated in analogy to the theory of neutron scattering by crystal. Some empirical formulas can be reproduced from rather natural assumptions on the correlation function of the above system of scattering centers.

Effects of the “Structure” of the pion to the pion-nucleon scattering are discussed. A formal expression of the interaction kernel for the nucleon-antinucleon propagator is given, from which the “effective Hamiltonian” for the emission and absorption of one pion and that for two pions are derived respectively. Effects of two pion vertex, which is characteristic of the structure of pion, seem to be not necessarily negligible compared with the effects of one pion vertex, according to a very rough estimate of the order of magnitude of the “coupling constant” appearing in the interaction kernel for the nucleon-antinucleon propagator. At present two standpoints are recognized with respect to the theory of pion, i.e., the compound theory of the pion and the conventional local pion field theory. However, we intended to discuss some important properties burried under both theories by using the above method, and obtained the qualitative properties concerning the isospin dependence of the pion-nucleon scattering matrix elements. Quantitative evaluation of the possible effects are not made, since for that purpose it is necessary to attack the details of the structure of the pion. Such an attempt is not made in the present paper. It is shown, in the Appendix, that the crossing symmetry for the pion-nucleon scattering holds even if the pion is considered to be composed of arbitrary number of fermion pairs and bosons, provided that the primary interaction Lagrangian satisfies the integrability condition to assure the existence of propagators.