A search for near infrared counterparts of 3 pulsar wind nebulae

TL;DR

This study searched for near-infrared counterparts of three pulsar wind nebulae in the Galactic plane but found no extended emission or new counterparts, highlighting the need for further observations and more precise positions.

Contribution

First near-infrared imaging attempt to identify counterparts of three PWN systems, setting constraints and guiding future observations.

Findings

No extended emission detected in any of the three PWN fields.

Confirmed the magnitude of a previously identified counterpart for IGR J18490-0000.

Further observations needed for definitive associations.

Abstract

While pulsar wind nebulae (PWNe) and their associated isolated pulsars are commonly detected at X-ray energies, they are much rarer at near infrared (nIR) and optical wavelengths. Here we examine three PWN systems in the Galactic plane - IGR J14003-6326, HESS J1632-478 and IGR J18490-0000 - in a bid to identify optical/nIR emission associated with either the extended PWNe or their previously detected X-ray point sources. We obtain optical/nIR images of the three fields with the ESO - New Technology Telescope and apply standard photometric and astrometric calibrations. We find no evidence of any extended emission associated with the PWNe in any of the fields; neither do we find any new counterparts to the X-ray point sources, except to confirm the magnitude of the previously identified counterpart candidate of IGR J18490-0000. Further observations are required to confirm the association of the nIR source to IGR J18490-0000 and to detect counterparts to IGR J14003-6326 and HESS J1632-478, while a more accurate X-ray position is required to reduce the probability of a chance superposition in the field of the latter.