Related papers: Circumstellar Magnetic Field Diagnostics from Line…
The physics of the Hanle effect is briefly reviewed, and its application as a diagnostic of hot star magnetic fields is described. Emphasis is given to the practicalities of using spectropolarimetry of resolved wind emission lines to infer…
Magnetic fields are important for stellar photospheres and magnetospheres, influencing photospheric physics and sculpting stellar winds. Observations of stellar magnetic fields are typically made in the visible, although infrared…
In this paper I will discuss new magnetic field diagnostics and instrumentation for an area of astrophysics where magnetic field observations have been difficult - circumstellar material. Such diagnostics would be particularly relevant to…
The Hanle effect has been proposed as a new diagnostic of circumstellar magnetic fields for early-type stars, for which it is sensitive to field strengths in the 1-300 G range. In this paper we compute the polarized P-Cygni line profiles…
The only way to obtain reliable empirical information on the intensity and topology of the weak magnetic fields of the quiet solar chromosphere is via the measurement and rigorous physical interpretation of polarization signals in…
This paper focuses on the polarized profiles of resonance scattering lines that form in magnetized disks. Optically thin lines from Keplerian planar disks are considered. Model line profiles are calculated for simple field topologies of…
Magnetic fields in our Galaxy and nearby galaxies have been revealed by starlight polarization, polarized emission from dust grains and clouds at millimeter and submillimeter wavelength, the Zeeman effect of spectral lines or maser lines…
Stellar magnetic dynamos are driven by rotation, rapidly rotating stars produce stronger magnetic fields than slowly rotating stars do. The Zeeman effect is the most important indicator of magnetic fields, but Zeeman broadening must be…
Direct measurements of magnetic fields in low-mass stars of spectral class M have become available during the last years. This contribution summarizes the data available on direct magnetic measurements in M dwarfs from Zeeman analysis in…
Measurements of interplanetary magnetic fields have long relied on spacecraft measurements, which provide only in-situ sampling and therefore cannot capture the global magnetic structure. Faraday rotation of radio signals extends in-situ…
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…
Diagnostic techniques for stellar magnetic fields based upon spectropolarimetry. We propose and explore a new technique based upon the linear polarization emitted in Hanle-sensitive lines in disk-integrated stars where a dipolar magnetic…
Magnetic fields are observed everywhere in the universe. In this review, we concentrate on the observational aspects of the magnetic fields of Galactic and extragalactic objects. Readers can follow the milestones in the observations of…
Stellar Magnetism affects all spectral types and exists and varies throughout the evolution of stars. Magnetic fields can affect not only the interior of stars, but also their circumstellar environments. In this chapter, we concentrate on…
The degree to which the formation and evolution of clouds and filaments in the interstellar medium is regulated by magnetic fields remains an open question. Yet the fundamental properties of the fields (strength and 3D morphology) are not…
Magnetic fields have been detected on stars across the H-R diagram and substellar objects either directly by their effect on the formation of spectral lines, or through the activity phenomena they power which can be observed across a large…
Weak entangled magnetic fields with mixed polarity occupy the main part of the quiet Sun. The Zeeman effect diagnostics fails to measure such fields because of cancellation in circular polarization. However, the Hanle effect diagnostics,…
Magnetic fields are an important ingredient to cool star physics, and there is great interest in measuring fields and their geometry in order to understand stellar dynamos and their influence on star formation and stellar evolution. During…
Magnetism is one of the most important forces on the interstellar medium (ISM), anisotropically regulating the structure and star formation that drive galactic evolution. Recent high dynamic range observations of diffuse gas and molecular…
The measurement of Zeeman splitting in spectral lines---both in emission and absorption---can provide direct estimates of the magnetic field strength and direction in atomic and molecular clouds, both in our own Milky Way and in external…