New pulsar wind nebula and its associated pulsar detected

A composite image of the galactic plane and the Potoro region. The red layer shows the 1368 MHz ASKAP full-intensity image, and the green and blue layers represent the 12 μm and 22 μm WISE infrared images, respectively. Known galaxy SNRs are marked with red circles (Green, 2019, 2022) and known galaxy HII regions are marked with green circles (Anderson et al., 2014). The table highlights the most interesting sections. The inset is an enlarged ASKAP image showing the potoro, with a red cross indicating the position of the X-ray source and a red dashed line representing the potoro’s axis of symmetry, which corresponds to the tail length studied in this article. Masu. Photo courtesy of arXiv (2023). DOI: 10.48550/arxiv.2312.06961

Astronomers discovered the pulsar candidate, designated PSR J1638-4713, using the Parkes Ultra Wide Low (UWL) receiver system. Additional observations of PSR J1638-4713 confirmed that it was powering Potoro.

Astronomers from Australia’s Western Sydney University and elsewhere have reported the discovery of a new pulsar wind nebula and the pulsars that feed it. The discovery, announced in a paper published on the preprint server arXiv on December 12, was made using the Australian Square Kilometer Array Pathfinder (ASKAP) with the MeerKAT and Parkes radio telescopes. A pulsar wind nebula (PWNe) is a nebula driven by pulsar winds. Pulsar winds are made up of charged particles. PWNs occur in a pulsar’s environment, especially when it collides with slowly expanding supernova ejecta.

Particles in PWNe lose energy due to radiation, and their energy decreases with increasing distance from the central pulsar. Multiwavelength studies of these objects (including his X-ray observations, especially using spatially integrated spectra in the X-ray band) have the potential to reveal important information about particle fluxes within these nebulae. there is. This may provide important insights into the nature of PWNe in general.

Now, a team of astronomers led by Sanja Lazarevic from Western Sydney University has discovered a new pulsar wind nebula using continuous radio surveys with ASKAP and MeerKAT. They named the new PWN “Potoroo,” after a small marsupial native to Australia. We then used the Parkes Ultra Wide Low (UWL) receiver system to discover a pulsar candidate designated PSR J1638-4713. Additional observations of PSR J1638-4713 confirmed that it was powering Potoro. Observations show that Potoro has a unique cometary morphology in both the radio and X-ray bands. This suggests that pulsars precede PWNs and are moving at supersonic speeds through the environment.

“For a pulsar propelling supersonically through its environment, the pressure converts the PWN into an arc burst. This process restricts the pulsar’s winds in the opposite direction of the pulsar’s motion, forming a type of comet. “The shape of the tail fin,” the author of the article explained. According to the study, Potoro is at least 32,500 light-years away, with a radius of about 68.5 light-years, but the X-ray appears to be less than a tenth of its size. This means Potoroo has the longest PWN radio title ever known. The results suggest that Potro’s overall radio spectrum is unusually steep, with a value of -1.27. This is below the known typical value of his PWNe. Astronomers suspect that such a significant overall spectral index is due to the backshock of the parent supernova and its interaction with the PWN.

source: https://arxiv.org/abs/2312.06961