Related papers: A Four-Stokes-Parameter Spectral Line Polarimeter …
Scattering polarization signals offer a unique diagnostics of the physical conditions in the solar atmosphere, in particular magnetic fields via the Hanle effect. However, their spatial structure remains poorly constrained due to the…
Magnetic fields are expected to play an important role in accretion processes for circumstellar disks. Measuring the magnetic field morphology is difficult, especially since polarimetric (sub)millimeter continuum observations may not trace…
Sr I 4607\AA spectral line shows one of the strongest scattering polarization signals in the visible solar spectrum. The amplitudes of these signals are expected to vary at granular spatial scales. This variation can be due to changes in…
We review the tools and procedures for the analysis of the data collected by X-ray photoelectric gas polarimeters, like the ones on-board the Imaging X-ray Polarimetry Explorer (IXPE). Although many of such tools are in principle common…
Magnetic fields of cool active stars are currently studied polarimetrically using only circular polarization observations. Including linear polarization in the reconstruction of stellar magnetic fields allows more information about the…
Wavelength-dependent polarization state of light carries crucial information about light-matter interactions. However, its measurement is limited to bulky, energy-consuming devices, which prohibits many modern, portable applications. Here,…
We completed observations with the Effelsberg 100-m radio telescope to measure the polarised emission from a complete sample of Compact Steep-Spectrum sources. We observed the sources at four different frequencies. We complemented these…
X-ray polarimetry promises to deliver unique information about the geometry of the inner accretion flow of astrophysical black holes and the nature of matter and electromagnetism in and around neutron stars. In this paper, we discuss the…
We report novel spectropolarimetric observations of sunspots carried out with the Tenerife Infrared Polarimeter (TIP) in a near-IR spectral region around 15410 A, which is known to contain two groups of prominent OH lines that show circular…
We developed a polarization modulation unit (PMU) to rotate a waveplate continuously in order to observe solar magnetic fields by spectropolarimetry. The non-uniformity of the PMU rotation may cause errors in the measurement of the degree…
An easily constructed and operated polarimeter precisely determines the relative Stokes parameters that characterize the polarization of laser light. The polarimeter is calibrated in situ without removing or realigning its optical elements,…
Nuclear physics experiments at Thomas Jefferson National Accelerator Facility's CEBAF rely on high polarization electron beams. We describe a recently commissioned system for prequalifying and studying photocathodes for CEBAF with a…
We use the POLARIS radiative transfer code to produce simulated circular polarization Zeeman emission maps of the CN $J = 1 - 0$ molecular line transition for two types of protostellar envelope magnetohydrodynamic simulations. Our first…
A telescope polarization model for the SST [Swedish 1-m Solar Telescope] is developed and the parameters of this model are fitted to polarization measurements made with a 1-meter linear polarizer in front of the entrance window. In this…
New linear polarization measurements (mainly in the V band) are presented for 203 quasi-stellar objects (QSOs). The sample is made up of 94 QSOs located in the North Galactic Pole (NGP) region and of 109 QSOs in the South Galactic Pole…
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…
We summarize in this paper the spectro-polarimetric methods used at the Pic du Midi Turret Dome in spectroscopic or imagery mode. The polarimeters and spectrograph allow the cartography of solar magnetic fields at high spatial resolution…
Many astronomical objects emit polarised light, which can give information both about their source mechanisms, and about (scattering) geometry in their source regions. To date (mostly) only the linearly polarised components of the emission…
We report Zeeman infra-red spectroscopy of electronic-nuclear levels of $^5$I$_8 \rightarrow ^5$I$_7$ transitions of Ho$^{3+}$ in the C$_{\rm 4v}$(F$^-$) centre in CaF$_2$ with the magnetic field along the $\langle 111\rangle$ direction of…
Aims. This research note presents a full analysis of the CAFOS polarimeter mounted at the Calar Alto 2.2m telescope. It also provides future users of this mode with all necessary information to properly correct for instrumental effects in…