Evidence for <i>L</i>-dependence generated by channel coupling: ¹⁶O scattering from ¹²C at 115.9 MeV

Background: In earlier work, inversion of S matrix for 330 MeV 16O on 12C resulted in highly undulatory potentials; the S matrix resulted from the inclusion of strong coupling to states of projectile and target nuclei. L-independent S-matrix equivalent potentials for other explicitly L-dependent potentials have been found to be undulatory. Purpose: To investigate the possible implications of the undulatory dynamic polarization potential for an underlying L dependence of the 16O on 12C optical potential. Methods: S matrix to potential, SL → V (r), inversion which yields local potentials that reproduce the elastic channel S matrix of coupled channel (CC) calculations, will be applied to the S matrix for 115.9 MeV 16O on 12C. Further, SL for explicitly L-dependent potentials are inverted and the resulting L-independent potentials are characterized and compared with the undulatory potentials found for 16O on 12C. Results: Some of the undulatory features exhibited by the potentials modified by channel coupling for 115.9 MeV 16O on 12C can be simulated by simple parameterized L-dependent potentials. Conclusions: The elastic scattering of 16O by 12C is a particularly favorable case for revealing the effective L dependence of the potential modified by channel coupling. Nevertheless, there is no reason to suppose that undularity is not a generic property leading in many cases to the choice: nucleus-nucleus potentials are (i) smooth and L-dependent, (ii) L-independent and undulatory, or (iii) both

Electronic integrator for gyro rate output voltages

Circuit which integrates spacecraft gyro output voltages to provide analog position signals has been developed. Accurate integration is provided by all solid state system which uses no choppers and takes advantage of commercially available flight qualified components

Suppression of Hall-Term Effects by Gyroviscous Cancellation in Steady Collisionless Magnetic Reconnection

The formation of an ion-dissipation region, in which motions of electrons and ions decouple and fast magnetic reconnection occurs, is demonstrated during a steady state of two-dimensional collisionless driven reconnection by means of full-particle simulations. The Hall-term effect is suppressed due to the gyroviscous cancellation at scales between the ion-skin depth and ion-meandering-orbit scale, and thus ions are tied to the magnetic field. The ion frozen-in constraint is strongly broken by nongyrotropic pressure tensor effects due to ion-meandering motion, and thus the ion-dissipation region is formed at scales below the ion-meandering-orbit scale. A similar process is observed in the formation of an electron-dissipation region. These two dissipation regions are clearly observed in an out-of-plane current density profile

Glauber-model analysis of total reaction cross sections for Ne, Mg, Si, and S isotopes with Skyrme-Hartree-Fock densities

A systematic analysis is made on the total reaction cross sections for Ne, Mg, Si, and S isotopes. The high-energy nucleus-nucleus collision is described based on the Glauber model. Using the Skyrme-Hartree-Fock method in the three-dimensional grid-space representation, we determine the nuclear density distribution for a wide range of nuclei self-consistently without assuming any spatial symmetry. The calculated total reaction cross sections consistently agree with the recent cross section data on Ne$+^{12}$C collision at 240$A$\,MeV, which makes it possible to discuss the radius and deformation of the isotopes. The total reaction cross sections for Mg$+^{12}$C, Si$+^{12}$C and S$+^{12}$C cases are predicted for future measurements. We also find that the high-energy cross section data for O, Ne, and Mg isotopes on a $^{12}$C target at around 1000\,$A$MeV can not be reproduced consistently with the corresponding data at 240\,$A$MeV.Comment: 10 pages, 14 figure