[en] Average s- and p-wave neutron resonance spacings (D_o, D₁) have long been one of the main sources of nuclear level density information. This paper is centered on the high resolution neutron total cross section measurements on ⁵²Cr, ⁵⁴Cr, ⁶⁷Zn and ⁸⁹Y isotopes made from a few eV to 1 MeV using pulsed neutron time of flight spectroscopy at Oak Ridge Electron Linear Accelerator (ORELA). R-matrix analysis of the data resulted in individual resonance parameters (E_o,J^π,g^τn) and average quantities like S_o, S₁, D_o, D₁. The experimental ratios of s- to p- wave level spacings were found to be in disagreement with the theoretical predictions. This indicates that the underlying assumptions ρ (l,J) α (2J+1) and ρ(l+1, J) ρ(l,J) are not valid in the theoretical expression. However, the (2J+1) spin dependence of level density has been checked over the years and found valid. Recently the data on D_o and D₁, for various nuclei have been compiled and the analysis indicates compelling evidence that level density depends on parity. The possible implication of the parity dependence of level density at high excitation energy in the calculation of compound and pre-compound contributions to the nuclear reactions along with theoretical aspects is presented

[en] Short communication. 5 refs., 1 fig

[en] In the present work, the level density parameters 'a' have been determined for a number of atoms within the frame work of Fermi gas model (FGM), Shifted Fermi gas model (SFM) and Independent Pairing model (IPM) using the latest precise values (corrected for missing levels) of D₀ (s-wave level spacing) based on high resolution neutron resonance spectroscopy

[en] E₂-transition probabilities between 4sub(g)sup(+)→2sub(g)sup(+), 2sub(g)sup(+)→0sub(g)sup(+) and 2sub(γ)sup(+) in even-even deformed nuclei of rare earth and actinide regions have been estimated using the asymmetric rotor model of Davydov and Rostovsky. The predictions of this model have been compared with the experimental values. From this comparison it has been found that the DR estimates are quite close to the experimental rates. The variations of the ratios B(E₂, 4sub(g)sup(+)→2sub(g)sup(+))sub(exp)/B(E₂, 4sub(g)sup(+))sub(DR), B(E₂, 2sub(g)sup(+)→0sub(g)sup(+))sub(exp)/B(E₂, 2sub(g)sup(+)→0sub(g)sup(+))sub(DR), B(E₂, 2sub(γ)sup(+)→0sub(g)sup(+))sub(exp)/B(E₂, 2sub(γ)sup(+)→0sub(g)sup(+))sub(DR) and B(E₂, 2sub(g)sup(+)→0sub(g)sup(+))sub(exp)/B(E₂, 2sub(g)sup(+)→0sub(g)sup(+))sub(SP) with non-axiality parameter 'γ₀' have been studied. (auth.)

[en] There is a well established need for accurate neutron capture and gamma ray production cross-section in the field of nuclear astrophysics, reactor design and materials damage estimation. The real challenge now is not to refine the well established statistical model, but to provide all the required ingredients like particle and γ-transmission coefficients, level density of excited states as reliable a way as possible

[en] In the present work, the fluctuations of Γ_f for 15 nuclei have been analysed with the emphasis on the best available data by a statistical procedure, maximum likelihood method (MLH) and graphical method (histogram)

[en] Short communication. 4 refs

[en] Published in summary form only

[en] Self supporting samples of Metglass 2204 (Ti₅₀Be₄₀Zr₁₀) and substrate bound samples of Metglass 2705M (Co₆₉B₁₂Si₁₂Fe₄Mo₂Ni₁) have been irradiated with 260 MeV ¹⁰⁷Ag and 130 MeV ²⁸Si ions, respectively at liquid nitrogen temperature. The surfaces have been examined by Scanning Electron Microscopy prior to and after irradiation. It is found that the surfaces have been smoothened after irradiation in both cases. The heights of the 'hills' have been decreased and the 'valleys' have been filled, without any detectable mass loss. The observed surface smoothing has been explained on the basis of shear flow mechanism within the framework of the viscoelastic model

[en] Short communication. 3 refs., 1 fig