Humanity has discovered only 31 magnetic neutron stars or magnetic, stellar objects with incredible magnetism. The new observations of one of these stars are not bizarre, but report behavior that has never been seen before, suggesting that these subjects may have more complex magnetic fields than previously thought.
The star is as Swift J1818.0-1607 or J1818 for short. It discovered just over a year ago and known as the fastest and youngest magnet, as well as a pulsar, a vibrating neutron star that has already received a lot of media attention. To this list of achievements, a new study published in the monthly notices of the Royal Astronomical Society adds another: it is the first magnet with a distorted magnetic pole.
J1818 is an incredible object. After discovered in March 2020, researchers noticed that it was becoming a “radio-loud”, reflecting the vibrations of radio waves like pulsars. In the summer, its emissions were a bright state and a choice between the weak. In July, the team saw a flashback between a “pulsar-like” state and a more classic “magnetic national” state.
“This bizarre behavior has never been seen before in any other radio-loud magnetic field,” lead author and graduate researcher at the University of Swinburne, Marcus Lower, said in a statement. “This only seems to be a short-term phenomenon as our next observation is that it was permanently located in this new magnetic nation state.”
The general idea of how magnets formed is by looking at the magnetic field at the opposite end of the star in a great north-south pole configuration. Instead the magnetic poles of J1818 are found close to each other near the equatorial region, the south dominating the radio emission.
“From our observations we have seen that the magnetic axis of J1818 does not converge with its axis of rotation,” Lower said. “Instead, the radio-emitting magnetic pole is located in the southern hemisphere just below the equator. Most other magnets have magnetic fields that combine with their spin axis or are somewhat obscure.”
The findings coincided with other studies that looked at magnets at wavelengths beyond radio. X-ray observations highlighted a single magnetic distortion. This could be two small but close distance poles as radio observations seem to suggest. The team plans to monitor regularly for any other changes in the magnetic field. Further studies could be something unique: mapping the magnetic field of a magnet for the first time.
