X-ray observations of the Large Magellanic Cloud pulsar PSR B0540-69 and its PWN

TL;DR

This paper presents a comprehensive X-ray analysis of the young pulsar PSR B0540-69 in the Large Magellanic Cloud, revealing spectral curvature and emission contributions from the pulsar and its PWN, with implications for pulsar emission models.

Contribution

It provides the first detailed spectral and timing analysis of PSR B0540-69 across multiple X-ray observatories, highlighting spectral curvature and emission component contributions.

Findings

Pulse shape shows no significant energy variation.

Pulsed spectrum is best fitted by a log-parabolic model.

Total emission analysis distinguishes pulsar and PWN contributions.

Abstract

PSR B0540-69 is a young pulsar in the Large Magellanic Cloud that has similar properties with respect to the Crab Pulsar, and is embedded in a Pulsar Wind Nebula. We have analyzed the complete archival RXTE dataset of observations of this source, together with new Swift-XRT and INTEGRAL-IBIS data. Accurate lightcurves are produced in various energy bands between 2 and 60 keV, showing no significant energy variations of the pulse shape. The spectral analysis shows that the pulsed spectrum is curved, and is best fitted up to 100 keV by a log-parabolic model: this strengthens the similarities with the Crab pulsar, and is discussed in the light of a phenomenologic multicomponent model. The total emission from this source is studied, the relative contributions of the pulsar and the PWN emission are derived, and discussed in the context of other INTEGRAL detected pulsar/PWN systems.