The Vela pulsar and its likely counter-jet in the K_s band

TL;DR

This study presents the first high-resolution near-infrared imaging of the Vela pulsar in the K_s band, detecting it firmly and revealing an extended feature likely associated with its X-ray counter-jet, providing new insights into its infrared emission.

Contribution

First high-resolution near-infrared imaging of the Vela pulsar in the K_s band, confirming the pulsar's flux and identifying a likely infrared counterpart to its X-ray counter-jet.

Findings

Pulsar detected at K_s ≈ 21.8 magnitude.

Extended feature likely associated with the X-ray counter-jet.

No strong infrared flux excess beyond the optical spectrum.

Abstract

We report the first high spatial resolution near-infrared imaging of the Vela pulsar in the $K_s$ band obtained with the new adaptive optics system recently mounted on the Gemini-South telescope. For the first time, we have firmly detected the pulsar in this band with $K_s$ $\approx$ 21\fm8, and have resolved in detail an extended feature barely detected previously in the immediate vicinity of the pulsar in the $J_sH$ bands. The pulsar $K_s$ flux is fully consistent with the extension of the flat optical spectrum of the pulsar towards the infrared and does not confirm the strong infrared flux excess in the pulsar emission suggested earlier by the low spatial resolution data. The extended feature is about two times brighter than the pulsar and is likely associated with its X-ray counter-jet. It extends $\sim$ 2\asec southwards of the pulsar along the X-ray ounter-jet and shows knot-like structures and a red spectrum.