Conveners
Polarization and stars
- Gianpiero Tagliaferri (INAF / Brera Astronomical Observatory)
Polarization and stars
- Gianpiero Tagliaferri (INAF / Brera Astronomical Observatory)
Polarization and stars
- Gianpiero Tagliaferri (INAF / Brera Astronomical Observatory)
-
Claudia Rodrigues (Instituto Nacional de Pesquisas Espaciais - INPE/Brazil)29/08/2022, 15:50Oral
This talk presents a revision of the literature relative to optical polarimetric measurements of cataclysmic variables (CVs). It is briefly introduced this kind of objects and the historical relevance of the detection of circular polarization in magnetic CVs. It is then discussed how polarization can be used to estimate important properties of those objects as the white-dwarf magnetic field,...
Go to contribution page -
Veronique Petit (University of Delaware, Bartol Research Institute)29/08/2022, 16:50Oral
Magnetic fields can be found at the surface of non-degenerate stars all over the HR diagram. Their nature is split between those contemporaneously generated by dynamo mechanism (e.g. low mass MS stars) and those of fossil origins (e.g. high mass MS stars). This means that there are fundamental differences in their observed properties — for example, while magnetic fields of low-mass stars are...
Go to contribution page -
Prof. Jamie Lomax (Department of Physics, U.S. Naval Academy)29/08/2022, 17:25Oral
Massive stars in WR+O systems are in a unique phase of their evolution; their strong and dense winds are thought to significantly affect their future evolution into GRBs, SNe, and ultimately inspiraling compact objects. Our team is carrying out an observational spectropolarimetric study of southern, WR+O star, colliding wind binaries to characterize their shock and wind structures using the...
Go to contribution page -
Andrew Hughes (University of Alberta)29/08/2022, 18:00Oral
Accretion-powered relativistic jets are a ubiquitous element of systems with accreting black holes. Despite the ubiquity of these jets, we have yet to construct a complete picture of the underlying mechanisms that control their evolution. In these jets, synchrotron emission leads to partial linear polarization, with fractional polarization levels and polarization angles that depend on the...
Go to contribution page -
Matheus Zaghi (Univsersidade de São Paulo)29/08/2022, 18:20Oral
About 10% of the known massive stars have strong, dipolar magnetic fields. Magnetohydrodinamical simulations show that the combination of strong magnetic fields and fast rotation can lead to the formation of co-rotating magnetospheres around these objects.
Go to contribution page
A theoretical model (the Ridigly Rotating Magnetosphere model, RRM) is available for the case of very strong magnetic fields. This model... -
Christi Erba (East Tennessee State University)30/08/2022, 09:00Oral
Massive stars are characterized by their intense luminosities and powerful, radiatively driven stellar winds. About 7% of massive stars also host strong (~1 kG), global magnetic fields, with stable, nearly dipolar magnetic topologies. These fields channel the stellar wind into a complex magnetosphere which has a significant impact on the star’s evolution. It is therefore critical to measure...
Go to contribution page -
Mr Ayan Biswas (National Centre for Radio Astrophysics)30/08/2022, 09:20Oral
Although > 6% of isolated massive stars are magnetic, a magnetic field is rarely observed (<1.5%) in the case of close hot binaries. Among them, $\epsilon$ Lupi A is the only close hot binary where both the components are magnetic. The stars have anti-aligned dipoles pointing to interacting magnetic fields, and orbit close enough that their magnetospheres are predicted to overlap, leading to...
Go to contribution page -
Richard Ignace30/08/2022, 09:40Oral
Massive star binaries are important for measuring stellar masses and stellar wind mass-loss rates. One obstacle is inferring viewing inclination and extracting information about the colliding wind interaction (CWI) region. Polarimetric variability from electron scattering in the winds and CWIs of massive stars provides information about system inclination and the geometry of the colliding wind...
Go to contribution page