Prof. ZHOU Xia from the Xinjiang Astronomical Observatory of the Chinese Academy of Sciences, along with her collaborators, has published a study in the Monthly Notices of the Royal Astronomical Society (MNRAS). The result sheds light on the formation mechanism of long-period radio pulsars.

Radio pulsars are rapidly rotating neutron stars whose electromagnetic radiation can be detected by telescopes on Earth. Prior to 2018, discovered pulsars exhibited rotational periods ranging from milliseconds to a few seconds, while long-period pulsars (with periods greater than 10 seconds) had not been found. With the continuous advancements in observational equipment in recent years, several radio pulsars with rotational periods exceeding 10 seconds have been discovered, posing new challenges to the understanding of pulsar formation and evolution.

The researchers investigated the formation mechanisms of three long-period pulsars (PSRs J0250+5854, J2251-3711, and J0901-4046). They explored the effects of three classical braking mechanisms—magnetic field decay, fallback disks, and r-mode instabilities—on the formation and evolution of long-period radio pulsars.

By comparing model predictions with multi-wavelength observational data, including rotational periods, period derivatives, and upper limits on thermal radiation luminosity, the researchers found that these braking mechanisms could reasonably explain the rotational periods and period derivatives of these pulsars within certain parameter ranges. Although the magnetic field decay model predicted a thermal radiation luminosity exceeding the upper limit for PSR J0901？4046, the predictions for the other two pulsars were within reasonable limits.