In this episode, we sit down with Dr. Taverna to delve into the mysterious world of magnetars—neutron stars with ultra-strong magnetic fields. While magnetars are primarily observed at x-ray wavelengths, the precise mechanisms and geometry of the emitting regions have remained a puzzle.

Dr. Taverna discusses their ground-breaking research that has taken a novel approach to studying these celestial bodies: measuring the x-ray polarization of the magnetar 4U 0142+61. These measurements revealed a fascinating and complex picture. The polarization degree and angle both change as a function of x-ray energy, pointing towards two distinct emission regions.

The conversation dives into the preferred model where most of the x-rays are emitted by an equatorial band on the neutron star's surface. Some photons then undergo scattering to higher energies due to collisions with electrons in the surrounding magnetic field. This reprocessing of thermal radiation provides new insights into the properties of the magnetar's magnetic fields and surface.

Join us as we uncover the secrets of magnetar emissions, guided by the intriguing insights drawn from x-ray polarization. It's an astronomical journey you don't want to miss!

Key Words: Magnetars, Neutron Stars, X-ray Polarization, Emission Regions, Magnetic Fields, Scattering, 4U 0142+61, Equatorial Band, Charged Particles, Magnetosphere.

https://doi.org/10.1126/science.add0080