Astronomers from Western Sydney University in Australia and elsewhere have reported the discovery of a new pulsar wind nebula and the pulsar that powers it. The discovery was presented in a paper published on the preprint server on December 12. arXiv It was made using the Australian Square Kilometer Array Pathfinder (ASKAP) and the MeerKAT and Parkes radio telescopes.

Pulsar wind nebulae (PWNe) are nebulae powered by the pulsar wind. The pulsar wind consists of charged particles; A PWN develops when the pulsar collides with its environment, specifically a slowly expanding supernova eruption.

Particles in PWNe lose their energy through radiation and become less energetic as they move further away from the central pulsar. Multiwavelength studies of these objects, including X-ray observations, especially using spatially integrated spectra in the X-ray range, have the potential to reveal important information about the particle flow in these nebulae. This could provide important insights into the nature of PWNe in general.

Now, a team of astronomers led by Sana Lazarevic from Western Sydney University has found a new pulsar wind nebula in ASKAP and MeerKAT’s radio continuum surveys. They named the new PWN “Potoroo” after the small marsupial that is native to Australia.

Then, using the Parkes Ultra Wideband Low (UWL) receiver system, they discovered a pulsar candidate called PSR J1638-4713. Subsequent observations of PSR J1638-4713 confirmed that it was feeding on Potoroo.

Observations show that Potoru exhibits characteristic comet morphology in both the radio and X-ray bands. This indicates that the pulsar is leading the PWN and is moving supersonic through the medium.

“For pulsars moving at supersonic speeds in the medium, the resulting shock pressure transforms the PWN into a shock. This process restricts the pulsar wind in the direction opposite to the direction of motion of the pulsar, creating a comet-like tail,” explained the authors of the paper.

According to the research, Potoru is at least 32,500 light-years away, with a radio magnitude of about 68.5 light-years, while its X-ray magnitude appears to be 10 times smaller. Thus, Potoru has the longest PWN radio paths known to date.

The results show that Potoru has an extremely steep total radio spectrum at -1.27. This is below typical values ​​for known PWNe. Astronomers suggest that such a sharp total spectral index may be the result of the interaction of the parent supernova’s rebound with the PWN.

PSR J1638-4713 has a spin period of 65.74 milliseconds and a dispersion measure of 1553 pc/cm.³ — the second largest of all known radio pulsars. Observations have shown that PSR J1638-4713 is a young pulsar (with a characteristic age of 24,000 years) with a high rotation luminosity and a large estimated speed exceeding 1000 km/s.