UV emission from young and middle-aged pulsars: Connecting X-rays with the optical

TL;DR

This study analyzes UV, optical, and X-ray data of three nearby pulsars to understand their multiwavelength emission properties and surface layer differences, revealing significant variability among middle-aged neutron stars.

Contribution

It provides new UV spectroscopy and timing data for three pulsars and connects their multiwavelength properties, highlighting differences in surface layers and thermal components.

Findings

Significant variability in multiwavelength properties among middle-aged pulsars.

Distinct thermal component differences between Geminga, B0656+14, and radio-quiet neutron stars.

Surface layer properties may explain observed emission differences.

Abstract

We present the UV spectroscopy and timing of three nearby pulsars (Vela, B0656+14 and Geminga) recently observed with the Space Telescope Imaging Spectrograph. We also review the optical and X-ray properties of these pulsars and establish their connection with the UV properties. We show that the multiwavelengths properties of neutron stars (NSs) vary significantly within the sample of middle-aged pulsars. Even larger differences are found between the thermal components of Ge-minga and B0656+14 as compared to those of radio-quiet isolated NSs. These differences could be attributed to different properties of the NS surface layers.