An attempt is made to give a consistent account of observed properties of the low-lying levels of the mirror nuclei 13C and 13N. In the first stage of this analysis, least squares fits of the data are made using R-matrix formulae in the one- and two-level approximations; in the second stage, the resultant parameter values are compared with shell model predictions. Fitted properties include level widths, neutron scattering data, El radiative widths and El capture cross sections .. The R-matrix formulae include external contributions to the El transition matrix elements, calculated using wavefunctions with the correct asymptotic forms. Acceptable fits are obtained for channel radii in the range 4-6 fm, with the lower values preferred. The parameter values obtained in these fits agree with shell model predictions, except for quantities involving the t - levels. Level displacement energies are calculated from the fitted parameter values. A reasonable account is given of two notable asymmetries between 13C and 13N-the very different excitation energies of the first excited states and the very different strengths of the El decays of these states.

This paper gives a survey of the alpha-nucleon interaction and then describes experimental work on angular distributions of differential scattering cross sections and polarizations in proton-alpha and neutron-alpha scattering. The phenomenological approach, which includes the study of both local and nonlocal potentials reproducing the experimental alpha-nucleon scattering data, is discussed. Basic studies of the alphanucleon interaction attempting to build an interaction between an alpha particle and a nucleon from first principles are then described. The authors then present a critical discussion of the results with some concluding remarks suggesting the direction for further investigation.

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Liquefaction can intensify the destruction caused by an earthquake; thus, a region with high liquefaction potential could be more disastrous. Bangladesh is surrounded by the Indo-Burma Folded Belt in the east, the Dauki Fault and Himalayan Syntaxis in the north that are known to have occurred high magnitude earthquakes (e.g., M w > 7) in the past. Therefore, assessing seismic hazards in the regions that are economically growing fast is of great interest. Among many other hazard assessment parameters, soil liquefaction potential index (LPI) can be used to assess seismic hazards. In this study, we have assessed the seismic hazard potential for a small town (Moulvibazar) in the northeast Bangladesh documenting liquefaction potential indices for different surface geological units using an earthquake of moment magnitude M w 8 having a peak horizontal ground acceleration (PGA) of 0.36 g. Twenty-five standard penetration test (SPT) boreholes were completed within the study area to obtain SPT-N values for two surface geological units: (1) Holo-Pleistocene low elevated terrace deposits (Zone 1) and (2) Holocene flood plain deposits (Zone 2). Using the SPT-N values, the LPI values have been calculated for the soil profile of each borehole. The LPI values in the town vary from 0 to 42.33, whereas values from 1.42 to 7.52 are in Zone 1 and values from 0 to 42.34 are in Zone 2. It has been predicted that 42% and 78% areas of Zone 1 and Zone 2, respectively, might exhibit surface manifestation of liquefaction. The results of this study can be used for seismic risk management of Moulvibazar town.

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