相关论文: Observations of solar scattering polarization at h…
[abridged] We investigate the effects of various AGN scattering region geometries on the polarized flux. We introduce a new, publicly available Monte Carlo radiative transfer code, Stokes, which models polarization induced by scattering off…
There is a thin transition region (TR) in the solar atmosphere where the temperature rises from 10,000 K in the chromosphere to millions of degrees in the corona. Little is known about the mechanisms that dominate this enigmatic region…
Spatial maps of the high-pass frequency filtered time-averaged root-mean-squared (RMS) Doppler velocities tend to show substantial decrements within regions of strong field and curiously, randomly distributed patches of enhancement in the…
Although the h and k lines of MgII are expected to be of great interest for probing the upper solar chromosphere, relatively little is known about their polarization properties which encode the information on the magnetic field. Here we…
The magnetic fields of the solar system planets provide valuable insights into the planets' interiors and can have dramatic consequences for the evolution of their atmospheres and interaction with the solar wind. However, we have little…
Theoretical investigations predicted that high spatio-temporal resolution observations in the Sr I 4607 A line must show a conspicuous scattering polarization pattern at the solar disk-center, which encodes information on the unresolved…
Recent observations with the HINODE satellite have found abundant horizontal magnetic fields in the internetwork quiet Sun. We compare the results on the horizontal fields with ground-based observations. We obtained 30 sec-integrated data…
This paper investigates the distribution of linear polarization signals in the quiet Sun internetwork using ultra-deep spectropolarimetric data. We reduce the noise of the observations as much as is feasible by adding single-slit…
Polarization speckle is a fine granular light pattern having spatially varying random polarization profile. We generate these speckle patterns by using the scattering of Poincar\'e beams, a special class of vector vortex beams, through a…
We report on spectropolarimetric observations across the Mg II h and k-lines at 2800 angstrom made by the Ultraviolet Spectrometer and Polarimeter onboard the Solar Maximum Mission satellite. Our analysis confirms the strong linear…
Hydrodynamic simulations of granular convection predict the existence of supersonic flows covering ~3-4% of the solar surface at any time, but these flows have not been detected unambigously as yet. Using data from the spectropolarimeter…
Here we report on the first observational investigation of the Zeeman effect in the G band around 4305 A. Our spectropolarimetric observations of sunspots with the Zurich Imaging Polarimeter at the IRSOL facility confirm our previous…
Magnetic field topology, thermal structure and plasma motions are the three main factors affecting the polarization signals used to understand our star. In this theoretical investigation, we focus on the effect that gradients in the…
In this work, we investigate if gravitational microlensing can magnify the polarization signal of a stellar spot and make it be observable. A stellar spot on a source star of microlensing makes polarization signal through two channels of…
A technique based on speckle contrast measurement is proposed and demonstrated to track the polarization rotation of an optical beam behind a scattering layer. It is shown that with the help of a reference speckle pattern with a known…
Scattering of anisotropic radiation by atoms, ions or molecules is sufficient to generate linear polarization observable in stars and planets atmospheres, circumstellar environments, and in particular in the Sun's atmosphere. This kind of…
We present measurements of circular polarization from rotational spectral lines of molecular species in Orion KL, most notably 12CO (J=2 - 1), obtained at the Caltech Submillimeter Observatory with the Four-Stokes-Parameter Spectra Line…
The detailed investigation of the polar magnetic field and its time evolution is one of the major achievements of Hinode. Precise measurements of the polar magnetic field are essential for understanding the solar cycle, as they provide…
When inverting solar spectra, image degradation effects that are present in the data are usually approximated or not considered. We develop a data reduction method that takes these issues into account and minimizes the resulting errors. By…
Direct imaging has paved the way for atmospheric characterization of young and self-luminous gas giants. Scattering in a horizontally-inhomogeneous atmosphere causes the disk-integrated polarization of the thermal radiation to be linearly…