Tensor coupling and vector mesons in dense nuclear matter

The effects of magnetic interaction between vector mesons and nucleons on the propagation (mass and width) of the \rho-meson in particular moving through very dense nuclear matter is studied and the modifications, qualitative and quantitative, due to the relevant collective modes (zero-sound and plasma frequencies) of the medium discussed. It is shown that the \rho-mesons produced in high-energy nuclear collisions will be longitudinally polarized in the region of sufficiently dense nuclear matter, in the presence of such an interaction

Phase Transitions In Two Planar Lattice Models And Topological Defects: A Monte Carlo Study

Monte Carlo simulation has been performed in the planar P(_{2}) and P(_{4}) models to investigate the effects of the suppression of topological defects on the phase transition exhibited by these models. Suppression of the 1/2-defects on the square plaquettes in the P(_{2}) model leads to complete elimination of the phase transition observed in this model. However in the P(_{4}) model, on suppressing the single 1/2-defects on square plaquettes, the otherwise first order phase transition changes to a second order one which occurs at a higher temperature and this is due to presence of large number of 1/2-pair defects which are left within the square plaquettes. When we suppressed these charges too, complete elimination of phase transition was observed.Comment: Related work has been presented in 22 nd International Conference on Statistical Physics, STATPHYS22, IISC Bangalore, Indi

Compact analogue neural network: a new paradigm for neural based combinatorial optimisation

The authors present a new approach to neural based optimisation, to be termed as the compact analogue neural network (CANN), which requires substantially fewer neurons and interconnection weights as compared to the Hopfield net. They demonstrate that the graph colouring problem can be solved by using the CANN, with only O(N) neurons and O(N2) interconnections, where N is the number of nodes. In contrast, a Hopfield net would require N2 neurons and O(N4) interconnection weights. A novel scheme for realising the CANN in hardware form is discussed, in which each neuron consists of a modified phase locked loop (PLL), whose output frequency represents the colour of the relevant node in a graph. Interactions between coupled neurons cause the PLLs to equilibrate to frequencies corresponding to a valid colouring. Computer simulations and experimental results using hardware bear out the efficacy of the approach

Hall Mobility of Tellurium Films Deposited on BaTiO3 Crystal

The measurements of electrical resistivity and Hall coefficient of tellurium films deposited on polarised barium titanate single crystals have been reported; the results on glass and mica substrate are also included for comparison. The results yield a value of surface state density for tellurium to be 15 X 1O 14/cm2 volt and the energy of the surface states 0.09 e.v. below the mid gap position

Effect of Nutrients and Plant Growth Regulators on Fruit Retention, Yield and Physico-Chemical Characteristics in Aonla Cv. NA-10

To check pre-mature fruit drop in aonla cv. NA-10, an investigation was undertaken during 2007 and 2008 in a Seven year old private orchard at Jhargram, Paschim Midnapore, West Bengal, where the soil is red laterite and pH ranges between 4.5 and 5.5. Treatments included foliar spray of urea (0.2%) + DAP (0.2%), ZnSO4 (0.5%), Borax (0.4%), NAA (10 and 20 ppm), Vermiwash (3 ml/l), Humaur (2 ml/l) and water spray (control). Results of two years of investigation revealed that spray of NAA at 10 ppm was the best to increase fruit retention, followed by NAA 20 ppm, Vermiwash and Borax, which consequently resulted in the highest fruit yield of 54.9, 52.0, 46.8 and 36.2 kg/plant, respectively, against 13.8 kg in the control. Fruit weight was maximum with 0.5% ZnSO4 spray, followed by NAA 10 ppm. Fruit quality with regard to TSS, total sugar and ascorbic acid content was better in all the treated fruits compared to control