Galactic magnetic fields

Linear polarization peaking in the visible Asymmetric particles aligned in galactic magnetic fields... 

Oort reported on Some Topics Governing the Structure and Evolution of Galaxies and described the latest knowledge concerning our Galaxy. Woltjer discussed the Galactic Magnetic Field. ... 

Because of interest at the time of writing, molecular ions in intense magnetic fields are treated briefly, with a comparison between terrestrial behaviour and electronic structure in intense galactic magnetic fields. In one of the Appendices, some related considerations on current density in atoms in magnetic fields will be studied. 

It is worth noting that the knee observed in the cosmic ray spectrum at 4 x 1015 eV may arise not in the sources but in the process of cosmic ray propagation in the Galaxy, e.g. as a result of interplay between ordinary and Hall diffusion in galactic magnetic fields [54], [Roulet 2004], Of course, this explanation requires the existence of a power-law source spectrum which extends without essential breaks up to about 1018 eV or even further. 

The propagation as described in diffusion models Kalmykov Pavlov 1999, Ogio Kakimoto 2003, Roulet 2004 yields (In A)-values presented in Fig. 6c. The models are based on the approach by Ptuskin et al. 1993, but take into account different assumptions on details of the propagation process, like the structure of galactic magnetic fields etc. This results in a more or less strong cut-off for the flux at the individual knees and, consequently, in a more or less strong increase of (In A). The model by Kalmykov Pavlov 1999 has been used to describe the observed spectra in Fig. 4. 

Stepanov R., Frick P., Shukurov A., Sokololf D.. Wavelet tomography of the Galactic magnetic field. I. The method Astronomy and Astrophysics. 2002 391 361-368. 

Polarization this polarization can be explained by an alignment of the non spherical dust particles due to the galactic magnetic field. 

The discovery of very strong magnetic fields in compact galactic objects, namely white dwarf stars (see, for instance, the review of Garstang [1]) and neutron stars ([2] see also [3] and references therein) has led to substantial efforts to understand the electronic structure of atoms subjected to such fields. 

At the current time in our Galaxy, it appears that star formation takes place in massive interstellar clouds, with dimensions 10 pc, density 5 x 109 atomsm-3, and temperature ss 10 K. The Galaxy is pervaded by a magnetic field aligned approximately parallel to the galactic plane. This magnetic field is strongly tied to the ionized plasma in the interstellar medium. 

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