They can produce beams of radio waves that sweep around the sky as the neutron star spins, producing routine flashes like cosmic lighthouses. Dr. Manisha Caleb, previously from The University of Manchester and now at the University of Sydney, who led the research study stated: “Amazingly we only detect radio emission from this source for 0.5% of its rotation period.” Amazingly we just discover radio emission from this source for 0.5% of its rotation period. It is currently uncertain how long this source has actually been releasing in the radio.” The radio emission from this neutron star is unlike any we have actually ever seen prior to,” explained Professor Ben Stappers at The University of Manchester and Principal Investigator of the MeerTRAP task.
Neutron stars are incredibly dense residues of a supernova explosion of a massive star. They can produce beams of radio waves that sweep around the sky as the neutron star spins, producing routine flashes like cosmic lighthouses. Scientists presently understand of about 3,000 of these in our own Milky Way galaxy. The brand-new discovery is unlike anything seen so far. The team thinks it could come from the theorized class of ultra-long period magnetars with incredibly strong electromagnetic fields.
South Africas MeerKAT telescope. Credit: South African Radio Astronomy Observatory (SARAO).
Dr. Manisha Caleb, formerly from The University of Manchester and now at the University of Sydney, who led the research study stated: “Amazingly we just discover radio emission from this source for 0.5% of its rotation duration. This means that it is extremely fortuitous that the radio beam converged with the Earth. It is for that reason likely that there are a lot more of these extremely gradually spinning sources in the Galaxy which has crucial implications for how neutron stars are born and age.
” The bulk of pulsar surveys do not search for durations this long therefore we have no concept how numerous of these sources there might be. In this case, the source was brilliant enough that we might identify the single pulses with the MeerTRAP instrument at MeerKAT.”.
” Amazingly we just spot radio emission from this source for 0.5% of its rotation duration. This means that it is extremely fortuitous that the radio beam converged with the Earth. It is therefore likely that there are many more of these extremely slowly spinning sources in the Galaxy which has important ramifications for how neutron stars are born and age.”.
— Dr. Manisha Caleb.
The recently found neutron star is called, PSR J0901-4046, and shows qualities of pulsars, (ultra-long period) magnetars, and even quick radio bursts. While the radio energy produced suggests a pulsar origin, the pulses with chaotic sub-pulse parts, and the polarization of the pulses are similar to magnetars.
While the spin duration of PSR J0901-4046 might be more consistent with a white dwarf, another less severe type of outstanding remnant, researchers do not see any multi-wavelength assistance for this. It is presently unclear for how long this source has actually been emitting in the radio. It was discovered in a well-studied part of the galaxy, but radio studies dont normally look for durations this long, or pulses that last more than a couple of 10s of milliseconds.
Dr. Manisha Caleb. Credit: University of Sydney.
” The radio emission from this neutron star differs from any we have actually ever seen prior to,” described Professor Ben Stappers at The University of Manchester and Principal Investigator of the MeerTRAP project. “We get to see it for about 300 milliseconds, which is much longer than for the majority of other radio giving off neutron stars. There seem to be at least 7 various pulse types, a few of which reveal highly routine structure, which might be translated as seismic vibrations of the neutron star. These pulses may be giving us vital insight into the nature of the emission mechanism for these sources.”.
” The sensitivity that MeerKAT offers, combined with the sophisticated searching that was possible with MeerTRAP and a capability to make simultaneous pictures of the sky made this discovery possible. Even then it took an eagle eye to acknowledge it for something that was potentially a genuine source due to the fact that it was so unusual looking!” stated Dr. Ian Heywood from the ThunderKAT group and the University of Oxford who collaborated on this study.
Spotting comparable sources is observationally challenging, which indicates that there might be a larger undiscovered population waiting to be revealed. This brand-new discovery contributes to the possibility of the existence of a new class of radio transients, the ultra-long period neutron stars, recommending a possible connection to the evolution of extremely magnetized neutron stars, ultra-long period magnetars, and quick radio bursts.
Reference: “Discovery of a radio-emitting neutron star with an ultra-long spin period of 76 s” by Manisha Caleb, Ian Heywood, Kaustubh Rajwade, Mateusz Malenta, Benjamin Willem Stappers, Ewan Barr, Weiwei Chen, Vincent Morello, Sotiris Sanidas, Jakob van den Eijnden, Michael Kramer, David Buckley, Jaco Brink, Sara Elisa Motta, Patrick Woudt, Patrick Weltevrede, Fabian Jankowski, Mayuresh Surnis, Sarah Buchner, Mechiel Christiaan Bezuidenhout, Laura Nicole Driessen and Rob Fender, 30 May 2022, Nature Astronomy.DOI: 10.1038/ s41550-022-01688-x.
Artist impression of the 76s pulsar (in magenta) compared to other more quickly spinning sources. Credit: Danielle Futselaar
A global team of astronomers has actually discovered an odd radio-emitting neutron star, which turns incredibly gradually, completing one rotation every 76 seconds.
The group of researchers says it is an unusual discovery as it lives in the neutron star graveyard where they do not expect to see any radio emission at all. The discovery was used the MeerKAT radio telescope in South Africa and published in the journal, Nature Astronomy on May 30, 2022. The research study was led by members of the ERC-funded MeerTRAP (More Pulsars and transients) group at The University of Manchester.
The source was at first discovered from a single flash, or pulse, by the MeerTRAP instrument whilst piggybacking on imaging observations being led by a different group, ThunderKAT. MeerTRAP and ThunderKAT then worked carefully together to puzzle out its origin. Combining the information from the 2 groups, it was then possible to validate the pulsations and get a precise position for the source, enabling detailed and more sensitive follow-up observations.
