Dynamics of methyl radical formation by 266 nm photolysis of xylenes and mesitylene

The 266 nm photodissociation of three xylene isomers and mesitylene leading to the formation of methyl radical was examined. The kinetic energy release profiles for the methyl radical were almost identical for all the three isomers of xylene and mesitylene, while substantial differences were observed for the corresponding profiles of the co-fragment produced by loss of one methyl group. This observation be attributed to the formation of the methyl radical from alternate channels. The total kinetic energy distribution profiles were rationalized based on the dissociation of {sp2}C–C{sp3} bond in the cationic state, wherein the {sp2}C–C{sp3} bond dissociation energy is lowered relative to the ground state. The dissocaiton in the cationic state follows a resonant three-photon absorption process, resulting in maximum total kinetic energy of about 1.6 – 1.8 eV for the photofragments. A results in. Fitting of the TKER distribution profiles to empirical function reveals that the dynamics of {sp2}C–C{sp3} bond dissociation is insensitive to the position of substitution but marginally dependent on the number of methyl groups.

Monte Carlo simulation of the measurement by the 2E technique of the average prompt neutron multiplicity as a function of the mass of fragments from thermal neutron-induced fission of 239Pu

Using a Monte Carlo method, we simulate the measurement, by the 2E technique, of the average prompt neutron multiplicity as a function of the mass of fragments from the thermal neutron-induced fission of 239Pu. The input data for the simulation, associated with the primary fragment mass (A), consist of the yield (Y), the distribution of the total kinetic energy characterized by its average ((TKE) ̅) and its standard deviation (σ_TKE), the average prompt neutron multiplicity (ν ̅_s, a sawtooth approach of experimental data), and the slope of neutron multiplicity against total kinetic energy (dν_s/d<TKE>). The output data, associated with the simulated as the fragment mass measured by the 2E technique (µ), consist of the yield (y), the distribution of the total kinetic energy characterized by its average ((tke) ̅) and its standard deviation (σ_tke), and the average prompt neutron multiplicity (ν ̅_µ). In the mass regions A≈115 and A>150, ν ̅_µ is higher than ν ̅_s. This result suggests that, in those mass regions, the 2E experimental values associated with the average neutron multiplicity are overestimated, referred to the corresponding to the primary fragments.

COMPUTING THE COMPLEX RADIUS DEPENDENCY AND THE TWO ANGLES VERSUS TIME IN THE HYDROGEN ATOM

Using the definition of the velocity of vacuum particles or streamlines from the Schrödinger equation, it was possible to determine the dependence of the radius and two angles on time. In the general case, several complex values of the radius and two angles were obtained as a function of time. But using continuous coordinates, it was possible to determine the change in the complex radius and two angles for the hydrogen atom. The resulting total kinetic energy of the atom differs from its own electrical energy, which provides the radiation of the atom.

Total kinetic energy release in the fast neutron induced fission of actinide nuclei

The total kinetic energy (TKE) release in the fast neutron-induced fission of various actinide nuclei was measured for neutron energies for En =2.6-100 MeV at the Weapons Neutron Research facility of the Los Alamos National Laboratory. The data are compared to the GEF model of the fission process. The variances of the TKE distributions appear to decrease with increasing Z and A of the fissioning systems.