Magnetoresistance originated from charge-spin conversion in ferromagnet

Transverse magnetoresistance in a ferromagnetic/nonmagnetic/ferromagnetic trilayer originated from charge-spin conversion by anomalous Hall effect is investigated theoretically. Solving the spin diffusion equation in bulk and using the spin-dependent Landauer formula at the ferromagnetic/nonmagnetic interface, an analytical formula of the transverse resistivity is obtained. The charge-spin conversion by the anomalous Hall effect contributes to the magnetoresistance in a manner proportional to the square of the spin anomalous Hall angle. The angular dependence of the magnetoresistance is basically identical to that of planar Hall effect, but has an additional term which depends on the relative angle of the magnetizations in two ferromagnets.Comment: 10 pages, 1 figure, conference proceeding of MMM 201

Progenitors of GRB originated in the dense star cluster

The evidences are given for the origin of the GRB progenitors from the ready stellar remnants in result of the dynamical interaction in the dense star clusters. In this way the close binaries of compact objects may form and then merge, often after ejecting from the parent cluster. The GRB may trigger star formation in the gaseous partiall sphere and occurence of the GRB afterglows near the star formation regions may be connected with the successive GRB origins in the same parent cluster. The observed distributions of GRB afterglows in Z and in distance to the galactic centers are compatible with the origin of many GRBs in the (present day classical) globular clusters, which were younger than 2 Gyr at the time of many GRBs events.Comment: Paper presented to the Second Roma Workshop on GRB in the afterglow era, October 200