Conveners
Exploring the Galaxy: Pulsars and Pulsar Wind Nebulae: Parallel-11
- Christo Venter (North-West University Potchefstroom Campus)
Fermi gamma-ray source lists have led to the discovery of many "spider" pulsars, tight binary systems in which the pulsars are evaporating their companions. Most of these have been found in radio searches targeting the Fermi sources, because the computational effort to find the pulsations by directly searching the gamma-ray data is tremendous. Using novel search methods, optical observations...
The Fermi Large Area Telescope (LAT) has detected ~250 gamma-ray pulsars in its > 10 years of operation. The gamma-ray emission from most of these pulsars peaks in the GeV range, where the LAT is most sensitive; perhaps not surprisingly, only a handful of them fall in the "soft" gamma-ray category. While Fermi pulsars are teaching us much about the pulsar mechanism, the full picture is still...
The ground-based discovery of pulsed $\gamma$-ray emission from four pulsars has marked the beginning of a new era in pulsar science. Recent kinetic simulations sparked a debate regarding the emission mechanism responsible for pulsed $\gamma$-ray emission from pulsars. Detection of the Vela pulsar up to $\sim$~100 GeV by H.E.S.S.\ and Fermi Large Area Telescope (LAT) provides evidence for a...
We report the modelling of the optical polarized emission of the white dwarf pulsar in the binary system AR Scorpii (AR Sco) in the framework of the striped pulsar wind model constrained by optical photopolarimetric data. One of the main goals of this work is to constrain the parameters, which describe the white dwarf pulsar magnetic field geometry. Besides, we determine the location of the...
Marsh et al. (2016; M16) detected radio and optical pulsations from the binary system AR Scorpii (AR Sco). This system, with an orbital period of 3.55h, is composed of a cool, low-mass star and a white dwarf with a spin period of 1.95min. X-ray pulsations have also been detected from this source (Takata et al. 2018). Optical observations by Buckley et al. (2017) showed that optical pulsations...
Axion-like particles (ALPs) are hypothetical very light neutral spin-zero bosons predicted by superstring theory which can oscillate into photons in the presence of external magnetic fields. ALPs are attracting increasing interest in the high- and very-high-energy (VHE) astrophysics, since they can explain several issues: they mitigate Universe transparency at VHE, explain why flat spectrum...
