相关论文: Observations of solar scattering polarization at h…
Super-Eddington accretion onto compact objects is expected to produce optically thick outflows with a funnel-shaped cavity that may collimate the emission. At inclinations higher than the grazing angle of the funnel, the central source is…
The near-Earth space weather is driven by the quick release of magnetic free energy in the solar corona. Probing this extremely hot and rarified region of the extended solar atmosphere requires modeling the polarization of forbidden and…
We study the inverse Compton scattering of solar photons by Galactic cosmic-ray electrons. We show that the gamma-ray emission from this process is substantial with the maximum flux in the direction of the Sun; the angular distribution of…
The Planck survey provides unprecedented full-sky coverage of the submillimetre polarized emission from Galactic dust, bringing new constraints on the properties of dust. The dust grains that emit the radiation seen by Planck in the…
Modern radio spectrometers make measurement of polarized intensity as a function of Faraday depth possible. I investigate the effect of depolarization along a model line of sight. I model sightlines with two components informed by…
We study the broadband polarization of hydrogen lines produced by scattering of radiation, in the presence of isotropic electric fields. In this paper, we focus on two distinct problems: a) the possibility of detecting the presence of…
Solar limb observations sometimes reveal the presence of a satellite lobe in the blue wing of the Stokes I profile from pixels belonging to granules. The presence of this satellite lobe has been associated in the past to strong line of…
The distribution and evolution of the magnetic field at the solar poles through a solar cycle is an important parameter in understanding the solar dynamo. The accurate observations of the polar magnetic flux is very challenging from the…
Stellar prominences detected in rapidly rotating stars serve as probes of the magnetism in the corona of cool stars. We have synthesized the temporal evolution of the Stokes profiles generated in the He I 10830 and 5876 A triplets during…
The observation of the polarization emerging from a rotating star at different phases opens up the possibility to map the magnetic field in the stellar surface thanks to the well-known Zeeman Doppler Imaging. When the magnetic field is…
Using turbulent MHD simulations (magnetic Reynolds numbers up to 8000) and Hinode observations, we study effects of turbulence on measuring the solar magnetic field outside active regions. Firstly, from synthetic Stokes V profiles for the…
This paper reviews some recent advances in the development and application of polarized radiation diagnostics to infer the mean magnetization of the quiet solar atmosphere, from the near equilibrium photosphere to the highly non-equilibrium…
The polarimetry of the light scattered by planetary surfaces is a powerful tool to provide constraints on their microstructure. To improve the interpretation of polarimetric data from icy surfaces, we have developed the POLarimeter for ICE…
Given that dynamically significant magnetic fields in at least some massive stars have now been measured, our contribution addresses the question, to what extent can fields be directly detected in circumstellar gas? The question speaks…
Context. Investigations of the magnetism of the quiet Sun are hindered by extremely weak polarization signals in Fraunhofer spectral lines. Photon noise, straylight, and the systematically different sensitivity of the Zeeman effect to…
Although the magnetic fields in the quiet Sun account for the majority of the magnetic energy in the solar photosphere, inferring their exact spatial distribution, origin, and evolution poses an important challenge because the signals lie…
We report on a new phenomenon of `alignment' of supergranulation cells in the polar regions of the Sun. Recent high-resolution datasets obtained by the Solar Optical Telescope onboard the Hinode satellite enabled us to investigate…
We present a comprehensive polarimetric study of 26 nearby molecular clouds in four far-infrared bands (53 $\mu$m to 214 $\mu$m) using 52 archival SOFIA/HAWC+ datasets. Far-infrared dust polarization observations probe the plane-of-sky…
Birmingham Solar Oscillations Network (BiSON) instruments use resonant scattering spectrometers to make unresolved Doppler velocity observations of the Sun. Unresolved measurements are not homogenous across the solar disc and so the…
Context: The scattering polarization of the infrared (IR) triplet of neutral oxygen (O\,\textsc{i}) near 777\,nm provides a powerful diagnostic of solar atmospheric conditions. However, interpreting such polarization requires a rigorous…