X-rays from the mode-switching PSR B0943+10

TL;DR

This study presents simultaneous X-ray and radio observations of PSR B0943+10, revealing correlated thermal and non-thermal emissions and detecting X-ray pulsations during the pulsar's faint mode for the first time.

Contribution

It provides new constraints on the spectral and variability properties of PSR B0943+10 and reports the first detection of X-ray pulsations during its faint mode.

Findings

Detection of X-ray pulsations during the faint mode

Presence of both pulsed thermal and unpulsed non-thermal emissions in both modes

Correlated variability between thermal and non-thermal components

Abstract

New simultaneous X-ray and radio observations of the archetypal mode-switching pulsar PSR B0943+10 have been carried out with XMM-Newton and the LOFAR, LWA and Arecibo radio telescopes in November 2014. They allowed us to better constrain the X-ray spectral and variability properties of this pulsar and to detect, for the first time, the X-ray pulsations also during the X-ray-fainter mode. The combined timing and spectral analysis indicates that unpulsed non-thermal emission, likely of magnetospheric origin, and pulsed thermal emission from a small polar cap are present during both radio modes and vary in a correlated way.