Both observations and modeling of magnetic fields in the diffuse interstellar gas of spiral galaxies are well developed but the theory has been confronted with observations for only a handful of individual galaxies. There is now sufficient data to consider statistical properties of galactic magnetic fields. We have collected data from the literature on the magnetic fields and interstellar media...

It has been nearly half a century since optical pumping techniques pioneered by Kastler1, Dehmelt2, and Bell and Bloom3,4 have been applied to sensitive measurements of magnetic fi elds5,6. Th e general idea of the method is that light that is near-resonant with an optical transition creates long-lived orientation and/or higher-order moments in the atomic ground state, which subsequently underg...

the rotation curves of a sample of 46 low- and high-surface brightness galaxies are considered in the context of milgrom's modi_ed dynamics (mond) to test a new interpolating function proposed by zhao et al. (2010) [1] and compare with the results of simple interpolating function. the predicted rotation curves are calculated from the total baryonic matter based on the b-band surface photometry,...

it is inferred from the symmetrical and luminous x-ray emission of fossil groups that they are mature, relaxed galaxy systems. cosmological simulations and observations focusing on their dark halo and inter-galactic medium properties confirm their early formation. recent photometric observations suggest that, unlike the majority of non-fossil brightest group galaxies (bggs), the central early-t...

We present a microscopic theory for multiple light scattering occurring in inhomo-geneous 3D media subject to an external magnetic eld. Magneto-optical eeects (the Faraday eeect and the Cotton-Mouton eeect) occur inside the small inhomogeneities. We thereby take into account the spatial anisotropy, time-reversal-symmetry breaking and birefringence caused by the magnetic eld, and discuss the con...

The strong increase in the ̄ux of relativistic electrons during the recovery phase of magnetic storms and during other active periods is investigated with the help of Hamiltonian formalism and simulations of test electrons which interact with whistler waves. The intensity of the whistler waves is enhanced signi®cantly due to injection of 10±100 keV electrons during the substorm. Electrons which...

We present data of proper motions of OH masers in the massive star-forming regions ON 1, K3-50, and W51 Main/South. OH maser motions in ON 1 are consistent with expansion at approximately 5 km s−1, likely tracing the expanding ultracompact H II region. Motions in K3-50 are faster and may be indicating the final stages of OH maser emission in the source, before the OH masers turn off as the H II...

X-ray spectroscopy performed by diierent astronomical spacecrafts has shown that many active late-type stars possess coronae. For such reason, the magnetic structure of stellar coronae has raised considerable interest and, by analogy with the Sun, it is generally assumed that stellar coronae are structured by magnetic elds having the shape of arcades. Most of those coronal magnetic eld conngura...

Giant pulsations are nearly monochromatic ULF-pulsations of the Earth's magnetic ®eld with periods of about 100 s and amplitudes of up to 40 nT. For one such event ground-magnetic observations as well as simultaneous GEOS-2 magnetic and electric ®eld data and proton ̄ux measurements made in the geostationary orbit have been analysed. The observations of the electromagnetic ®eld indicate the exc...

Imaging polarimetry of the 850 km continuum emission in the NGC 7538 region, obtained with the SCUBA Polarimeter, is presented. The polarization map is interpreted in terms of thermal radiation by magnetically aligned dust grains. Two prominent cores associated with IRS 1 and IRS 11, IRS 1(SMM), and IRS 11(SMM), are found in the surface brightness map. Although these cores look similar in surfa...