Revealing Cosmic Magnetism with Radio Polarimetry
نویسنده
چکیده
While gravitation sustains the on-going evolution of the cosmos, it is magnetism that breaks gravity’s symmetry and that provides the pathway to the non-thermal Universe. By enabling processes such as anisotropic pressure support, particle acceleration, and jet collimation, magnetism has for billions of years regulated the feedback vital for returning matter to the interstellar and intergalactic medium. After reviewing recent results that demonstrate the unique view of magnetic fields provided by radio astronomy, I explain how the Square Kilometre Array will provide data that will reveal what cosmic magnets look like, how they formed, and what role they have played in the evolving Universe.
منابع مشابه
Magnetic Visions: Mapping Cosmic Magnetism with Lofar and Ska
The origin of magnetic fields in the Universe is an open problem in astrophysics and fundamental physics. “Cosmic Magnetism” has been accepted as Key Science Project both for the Low Frequency Array (LOFAR, under construction) and the planned Square Kilometre Array (SKA). At low frequencies LOFAR and SKA will allow to map the structure of weak magnetic fields in the outer regions and halos of g...
متن کاملMagnetic fields in nearby galaxies: prospects with future radio telescopes
The origin of magnetic fields in the Universe is an open problem in astrophysics and fundamental physics. Our present-day knowledge is limited to regions of strong magnetic fields and to starforming disks of galaxies. Cosmic-ray electrons emitting at high (GHz) radio frequencies can propagate only a few kpc from their places of origin due to their lifetime limited by energy losses. Low-energy e...
متن کاملInterferometric polarimetry of the cosmic microwave background: Methodology
Interferometry has long been used in radio astronomy to enable imaging of astronomical sources with angular resolutions exceeding the diffraction limit of a single aperture. In the past decade, interferometry of the CMB has been carried out with instruments such as the CBI, DASI and VSA which exploited the inherent instrumental stability and simplicity of ell-space analysis of interferometer da...
متن کاملTransport of cosmic rays in the nearby starburst galaxy NGC 253 ⋆
Radio halos require the coexistence of extra-planar cosmic rays and magnetic fields. Because cosmic rays are injected and accelerated by processes related to star formation in the disk, they have to be transported from the disk into the halo. A vertical large-scale magnetic field can significantly enhance this transport. We observed NGC 253 using radio continuum polarimetry with the Effelsberg ...
متن کامل