In this study we present simultaneous low-resolution longitudinal magnetic field measurements and high-resolution spectroscopic observations of the cool single giant FK Com. The variation of the magnetic field over the rotational period of 2.4 days is compared with the starspot location obtained using Doppler imaging techniques, V-band photometry and V-I colours. The chromospheric activity is s...

Hanle-effect observations of forbidden coronal line transitions and recently also longitudinal Zeeman-effect measurements of coronal lines show quantitative signatures of the weak coronal magnetic field. The interpretation of these observations is, however, complicated by the fact that they are the result of line-of-sight integrations through the optically thin corona. We study by means of simu...

We investigate the charge and spin response functions of a bilayer quasi-two-dimensional system, spin polarized by a constant magnetic field BW . Terms beyond the random-phase approximation, the exchange and correlation interactions, are introduced by using generalized spin-dependent local field factors, Gs x (qW ,v). The self-consistent magnetic interaction among the electron spins determines ...

We present a method for removing the ambiguity in the transverse component of the photospheric magnetic field measured by vector magnetographs. The method is based upon the use of the divergence-free condition satisfied by the magnetic field in the sense of least squares. The method requires the measurement of the longitudinal component of the magnetic field at two depth levels in the photosphe...

Ferrite magnets have a long history. They are used in motors, magnetic fluids, drug delivery systems, etc. Herein we report a mesoscopic ferrite bar magnet based on rod-shaped ε-Fe2O3 with a large coercive field (>25 kOe). The ε-Fe2O3-based bar magnet is a single crystal with a single magnetic domain along the longitudinal direction. A wide frequency range spectroscopic study shows that the cry...

PURPOSE We investigated the temporal variation of the induced magnetic field due to the transverse and the longitudinal gradient coils in tungsten collimators arranged in hexagonal and pentagonal geometries with and without gaps between the collimators. METHODS We modeled x-, y-, and z-gradient coils and different arrangements of single-photon emission computed tomography (SPECT) collimators ...

We have completed a new study of the formation of hydrogen lines in dense magnetized plasmas. We have developed a global formalism including the effects of the magnetic field and of the motional electric field. The latter, resulting from the motion of the radiating hydrogen atom in the magnetic field, modifies the structure of the matrices appearing in the equation of transfer of the Stokes vec...

Magnetic behavior of a spin-1 Heisenberg dimer is analysed in dependence on both uniaxial single-ion anisotropy and XXZ exchange anisotropy in a zeroas well as non-zero longitudinal magnetic field. A complete set of eigenfunctions and eigenvalues of the total Hamiltonian is presented together with an exact analytical expression for the Gibbs free energy, longitudinal magnetization, longitudinal...