相关论文: Exploring the Magnetic Field Geometry in NGC 891 w…
Magnetic fields in the ionized medium of the disk and halo of the Milky Way impose Faraday rotation on linearly polarized radio emission. We compare two surveys mapping the Galactic Faraday rotation, one showing the rotation measures of…
NGC 891 is a nearby edge-on galaxy that is similar to the Milky Way and has a hot X-ray emitting halo that could arise from accretion, a galactic fountain, or a combination of the two. The metallicity of the gas can help distinguish between…
Broadband continuum images of the edge-on galaxy NGC 891 at 850 and 450 microns are presented. These images are qualitatively very similar to the 1300 micron and CO images obtained by others. With respect to the 850 micron continuum, CO is…
The HH 1-2 region in the L1641 molecular cloud was observed in the near-IR J, H, and Ks bands, and imaging polarimetry was performed. Seventy six point-like sources were detected in all three bands. The near-IR polarizations of these…
We present a high-resolution VLA study of the total power and polarized radio continuum emission at 8.46 and 4.86 GHz of the irregular galaxy NGC 4449, known for its weak rotation and non-systematic gas motions. We found strong galaxy-scale…
Bursts of localized star formation in galaxies can levitate material from their midplanes. Spiral galaxies that are edge-on allow clear distinction of material that is levitated off the galaxies' midplanes. We used SOFIA to measure the…
We present neutral hydrogen observations of the nearby edge-on spiral galaxy NGC891 which show extended extra-planar emission up to distances of 15 kpc from the plane. 3D modeling of the galaxy shows that this emission comes from halo gas…
Galaxies are thought to grow through accretion; as less massive galaxies are disrupted and merge over time, their debris results in diffuse, clumpy stellar halos enveloping the central galaxy. Here we present a study of the variation in the…
We present 21-cm observations and models of the HI kinematics and distribution of NGC 4244, a nearby edge-on Scd galaxy observed as part of the Westerbork Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) survey. Our models give insight into…
Neutral gas is commonly believed to dominate over stars in the outskirts of galaxies, and investigations of the disk-halo interface are generally considered to be in the domain of radio astronomy. This may simply be a consequence of the…
Millimeter-wavelength polarization measurements offer a promising method for probing the geometry of magnetic fields in circumstellar disks. Single dish observations and theoretical work have hinted that magnetic field geometries might be…
The neutral hydrogen line profiles along the major axis of the nearby spiral galaxy NGC 2403 show a wing towards the sytemic velocity. This asymmetry can be explained with the presence of an abnormally thick HI disk (FWHM ~ 5 kpc) or with a…
The study of gas outside the plane of disc galaxies is crucial to understanding the circulation of material within a galaxy and between galaxies and the intergalactic environment. We present new HI observations of the edge-on galaxy NGC891,…
The polarized synchrotron data of the northern C-BASS survey show a surprisingly low linear polarization fraction, $\Pi\simeq 3\%$, while the magnetic field polarization features coherent structures over rather large angular scales. The low…
A sample of large northern Spitzer Infrared Nearby Galaxies Survey (SINGS) galaxies was recently observed with the Westerbork Synthesis Radio Telescope (WSRT) at 1300-1760 MHz. In Paper II of this series, we described sensitive observations…
After a short introduction on how we get information of the magnetic fields from radio observations I discuss the results concerning the magnetic field structure in galaxies: Large-scale regular magnetic field pattern of spiral structure…
Most of the visible mass in a typical spiral galaxy is distributed in a thin disk, with a radial extent much larger than its thickness. While the planar disk structure, including non-axisymmetric features such as spiral structure, has been…
Context. The distribution of elements in galaxies forms an important diagnostic tool to characterize the system's formation and evolution. This tool is however complex to use in practice, as galaxies are subject to a range of simultaneous…
Spiral galaxies host dynamically important magnetic fields which can affect gas flows in the disks and halos. Total magnetic fields in spiral galaxies are strongest (up to 30 \muG) in the spiral arms where they are mostly turbulent or…
We present a study of ionized gas, PAHs, and molecular hydrogen emission in the halos of three edge-on galaxies, NGC 891, NGC 5775 and NGC 3044, based on 10-20 micron Spitzer Space Telescope spectra. The [Ne III]/[Ne II] ratio, an excellent…