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![These maps show the degree of polarization of a face-on spiral galaxy at the observing frequency 8.5 GHz. (a) Map of the degree of polarization without including depolarization models. (b) Wavelengthindependent depolarization model with isotropic turbulent magnetic fields [equation (6)]. (c) Wavelength-independent depolarization model with anisotropic turbulent magnetic fields [equation (4)].](publication/366961605/figure/fig3/AS:11431281111836444@1673229072861/These-maps-show-the-degree-of-polarization-of-a-face-on-spiral-galaxy-at-the-observing.jpg)
These maps show the degree of polarization of a face-on spiral galaxy at the observing frequency 8.5 GHz. (a) Map of the degree of polarization without including depolarization models. (b) Wavelengthindependent depolarization model with isotropic turbulent magnetic fields [equation (6)]. (c) Wavelength-independent depolarization model with anisotropic turbulent magnetic fields [equation (4)].
Source publication
Studies of the three-dimensional structures of galactic magnetic fields are now entering a new era, with broad-band, highly sensitive radio observations and new analysis methods. To reveal the magnetic field configuration from the observed intensities integrated along the line of sight, it is necessary to derive an appropriate model involving vario...
Contexts in source publication
Context 1
... map reflects the magnetic spiral arm structure of the galactic disk and is consistent with our previous study (Machida et al. 2018). Figure 4 shows the effects of wavelength-independent depolarization. Panels (a), (b), and (c) show the case with no depolarization, with isotropic turbulence, and with anisotropic turbulence, respectively. ...
Context 2
... the energy of the turbulent magnetic field is calculated assuming a Gaussian distribution, the azimuthal turbulent magnetic field is also the dominant component. In figure 4c, the wavelength depolarization is calculated taking into account anisotropic turbulence. In this case, the degree of polarization exceeds 0.6 over the entire region due to the weakened effect of depolarization. ...
Context 3
... we consider depolarization effects using pseudoobservations at 0.15 GHz ( figure 14). We assume that these are observations of IC 342 at a resolution of 25 . ...
Context 4
... real galactic gas disks form high-density, cold gas disks, and these regions have strong magnetic fields. In fact, the central region in figure 14 where the polarization intensity shows a maximum value should be composed of cold gas. Such a high-density region would be expected to have stronger depolarization than the current model. ...
Context 5
... in order to calculate the depolarization effect correctly, a multi-temperature disk must be taken into account. Compared with the three-dimensional structure of polarized radiation shown in figure 13, the right panel of figure 14 shows that the magnetic field structure of the halo is being observed, as shown in the previous section. If LOFAR were used to observe with the NL-remote, even 3σ detection of such weak halo magnetic fields requires an observation time of 10 5 h or more (van Haarlem et al. 2013). ...
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