120865802
High spin spectroscopy and shears mechanism in In 107
High spin states of $^{107}\mathrm{In}$ have been investigated using the reaction $^{94}\mathrm{Mo}$($^{16}\mathrm{O}$,$p2n$)$^{107}\mathrm{In}$ at a beam energy of $70$ MeV. A total of $62$ new $\ensuremath{\gamma}$ transitions have been placed in the level scheme and several $\ensuremath{\Delta}I=1$ sequences and one $\ensuremath{\Delta}I=2$ sequence have been found. Lifetime measurements using the Doppler-shift attenuation method (DSAM) have been carried out for band states of $\ensuremath{\Delta}I=1$ and $\ensuremath{\Delta}I=2$. A decreasing trend of $B(M1)$ strengths with increasing spin deduced for the $\ensuremath{\Delta}I=1$ band indicates the presence of a shears mechanism. The experimental data for this band are compared with the tilted axis cranking (TAC) calculations. The $\ensuremath{\Delta}I=2$ band has been found to be a deformed band with ${\ensuremath{\beta}}_{2}~0.2$.
116623275
Experimental study of nuclei in the vicinity of the 'island of inversion' through the fusion-evaporation reaction
We report the observation of high-spin states in nuclei in the vicinity of the 'island of inversion', populated via the {sup 18}O+{sup 18}O fusion reaction at an incident beam energy of 34 MeV. The fusion reaction mechanism circumvents the limitations of other reactions used so far to populate excited states in these nuclei. The level structures of {sup 33,34}P and {sup 33}S have been investigated and their level schemes were substantially extended. The intensities and branching ratios of the {gamma} transitions were measured. The observed {gamma} coincidence intensity anisotropy and polarization asymmetry were analyzed for a consistent assignment of the spins and parities of the nuclear levels. The 1876-keV transition in {sup 34}P that had an ambiguous multipolarity assignment has been confirmed to be a mixed transition. Truncated (1p-1h) shell model calculations within the 'sdpf' valence space were performed. These calculations reproduce the experimental excitation energies of {sup 34}P but fail to explain the observed mixing ratio for the 1876-keV transition.
14630427
Spectral distortions at super-kamiokande
We examine the effect of the rise in the survival probability of the electron neutrinos with the decrease in the neutrino energy on the recoil electron spectrum at Super-Kamiokande.
118619694
On nuclear stopping in asymmetric colliding nuclei
Abstract Using the isospin-dependent quantum molecular dynamics (IQMD) model, nuclear stopping is analyzed in asymmetric colliding channels by keeping the total reacting mass fixed. The calculations have been performed by varying the mass asymmetry of the colliding pairs with different neutron–proton ratios at an incident beam energy of 250 MeV/nucleon. We find sizable effects of mass asymmetry on nuclear stopping and on the equilibrium of the nuclear matter. A reasonable agreement is also observed between the experimental data and our present calculations.
116542469
Study of gold induced heavy ion collisions using isospin dependent QMD model
We have studied the fragment production mechanism in the set of four reactions 197Au79+12C6, 197Au79+26Al13, 197Au79+63Cu29 and 197Au79+208Pb82. The reactions are simulated at an energy 600 MeV/nucleon and collision geometry is varied from central to peripheral (= b/bmax = 0 to 1). A theoretical investigation has been carried out on the study of mass dependence of intermediate mass fragments (5\leqA\leqAtot/6) and other fragments. It is observed that multiplicity shows a good agreement for low Zbound, but it fails for high Zbound. This failure is due the method of analysis MST which we had used in our analysis, because MST method gives one heavy cluster at the time of high density. The discrepancy between theory and experiments can be removed by using reduced isospin dependent NN cross section and sophisticated clustrization algorithm SACA.
119399108
LAGRANGIAN AND HAMILTONIAN FORMULATIONS OF HIGHER ORDER CHERN–SIMONS THEORIES
We consider models involving the higher (third) derivative extension of the Abelian Chern–Simons (CS) topological term in D = 2 + 1 dimensions. The polarization vectors in these models reveal an identical structure with the corresponding expressions for usual models which contain, at most, quadratic structures. We also investigate the Hamiltonian structure of these models and show how Wigner's little group acts as a gauge generator.
117335698
Effect of isospin dependent cross-section on nuclear stopping
Nuclear stopping in heavy ion collisions (HIC) has been studied by means of rapidity distribution and asymmetry of nucleon momentum distribution. It is an important quantity in determining the outcome of a reaction. Fen Fu {\it et al.,} \cite{2} calculate both the radial flow and the degree of nuclear stopping in Pb + Pb and Ni + Ni at 0.4, 0.8 and 1.2 GeV/neucleon. They found that the expansion velocity as well as the degree of nuclear stopping are higher in the heavier system at all energies.