BEIJING, Aug. 20 (Xinhua) — Chinese scientists have discovered a new form of radiation emission from pulsars, called “dwarf pulsars”, by using the China FAST Telescope, a spherical radio telescope with a diameter of up to 500 meters.
The discovery was recently published in the journal Nature Astronomy.
According to the study, pulsars emit radio signals when they rotate. However, some ancient pulsars often stop radiating for some periods, a phenomenon called “nullification”. The mechanism responsible for this is still unknown, as it is difficult to probe the magnetosphere during the voiding state due to the lack of measurements of the radioactive emissions.
With the high sensitivity of the “Fast” telescope, scientists from the National Astronomical Observatories of the Chinese Academy of Sciences have detected sporadic, weak and accurate pulses in the state of invalidity of the “B2111 + 46” pulsar. They called this new form of pulses dwarf pulses, which are difficult to monitor with other radio telescopes.
Further analysis shows that the magnetic field structure in the dwarf emitting region remains unchanged compared to the magnetic field structure of the normal emitting region. It reveals the physical fact that the magnetic structure of a pulsar basically does not change when its radiation is almost extinguished, said Han Jinlin, a senior research scientist on the work with the National Astronomical Observatories.
The study notes that while the radio emission of normal pulses is radiated by a “thunderstorm” of particles in the magnetosphere, the dwarf pulses are produced by one or a few “raindrops” of particles in the magnetosphere.
Hahn said these pulses can help reveal the mysteries of pulsars’ radiation processes and the plasma extremes within those stars’ magnetospheres.
