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Abstract: We attempt a general phenomenological analysis of the neutral weak current in the inclusive neutrino reactions using the parton model as a tool. From the recently reported data on these processes we determine the strengthH of the neutral-current interaction as well as the amount of theVA interference. We find (H/G)2=0·54±0·06 whereG is the Fermi coupling constant and theVA interference contribution turns out to be 33±23%. We also discuss the comparison of the data with various models for the neutral hadronic current.

We give plausible interpretations of the unusual events seen in the proton decay detector at Kolar Gold Fields indicating the existence of a massive (≳2GeV) long lived (10−8−10−9s) particle. We show that it is possible to accommodate the particle in the standard model as a fourth generation neutrino, or inE6grand unified theory as a neutral fermion occurring in27representation or in supersymmetric theory as a scalar neutrino. However, there is a difficulty in explaining the large production rate for the particle.

Abstract: In order to reconcile the life time of the new particle observed in the cosmic ray neutrino experiment with its production rate, it is proposed that the particle has a new quantum number (κ) which may be assigned to leptons and hadrons. In the production of the new particle, assumed to be a heavy charged lepton,κ is conserved by creating an associated lepton-hadron pair. Suppression of theκ-violating interaction is invoked to interpret the long life time of this particle.

Abstract: On the basis of some general assumptions on the deep inelastic structure functions, such as scaling and chiral symmetry we determine the values of {(H V3)2+(H A3)2}+η{(H V0)2+(H A0)2} andH V3 H A3+ηH V0 H A0 whereH V3,0 andH A3,0 are the four coupling constants characterizing the hadronic neutral current andη is the ratio of the isoscalar to isovector structure functions. General expressions are given for the kinematical averages 〈v〉 and 〈Q 2〉 for the neutral-current reactions in terms of the coupling constants. This analysis does not depend on the validity of the quark-parton model.

Abstract: We show that experimental data on inclusive neutrino reactions can be used to obtain general bounds on the coupling constants of the isovector part of the hadronic weak neutral current provided this isovector current is related to the charged current by isospin rotation. These bounds are free from the assumption of a specific model for the neutral current as well as any dynamical assumption on the hadronic structure functions. We derive upper bounds on the coupling constants which involve only the cross sections for isospin-averaged nucleon target as well as lower bounds which require a knowledge of the cross sections for proton and neutron separately.

Abstract: It is pointed out that the coupling characterizing theψ-γ vertex must change substantially between the limits,ψ on mass-shell which occurs inψ→e + e − and photon on mass-shell which is relevant in radiative decays likeψ→ππγ, ψ→ηγ and photoproduction ofψ. This has the consequence that the value ofψN total cross section must be larger than what is inferred from the use of naive vector dominance in photoproduction.

Abstract: The possible presence of anI=0 axial vector piece in the hadronic neutral current may be detected by looking for an asymmetry in the emission of the recoil deuterons in elastic scattering of neutrinos or antineutrinos on polarized deuterons. It is estimated that this asymmetry could be about 40% with the incident neutrinos in the energy range of tens of MeV.

Total photon mass attenuation coefficients in C, Al, S, Ti, B2O3, LiF, ZnO, Y2O3and H8O2C5(perspex) are measured on a good geometry set-up using proportional counter, Si(Li) and Ge(Li) detecting systems in the energy region from 6.47 to 52.014 keV employing x-rays and gamma rays from radioactive sources. The deduced photoelectric cross-sections are found to agree with the theoretical values of Storm and Israel, Scofield and semiexperimental values of Veigele wherever available within a few percent. The photo-electric cross-sections in elements, S, Ti and Y at their respectiveK-edges obtained by extrapolation technique agree with the theoretical values of Storm and Israel and Scofield at the respectiveK-edges except in S. In the case of S both the theoretical values atK-edges are found to be underestimations, more in the case of Scofield evaluations.

Abstract: A connection between the elastic scattering and the inclusive one-particlek T 2 distribution is pointed out in the context of thes channel unitarity. One of the implications of this connection is that the slope of thek T 2 distribution atk T 2 =0 is about a factor two larger than the slope of the elastic scattering att=0.

Abstract: The prong-number distributions in $$\bar pp$$ collisions at relatively low laboratory momenta (≾7 GeV/c) exhibit the same type of scaling which has been observed in pp and π-N collisions at momenta ≿ 50 GeV/c.