Astronomers from Nanjing University in China and elsewhere, using the Five Hundred Meter Aperture Spherical Radio Telescope (FAST), have discovered a radio pulsar known as CTB 87 in the supernova remnant, according to a paper published Feb. 1 by the preprint server arXiv . .

Pulsars are strongly magnetized, rotating neutron stars that emit a beam of electromagnetic radiation. They usually appear as short bursts of radio radiation; but some are also observed using optical, X-ray and gamma-ray telescopes.

CTB 87 is a plelerionic supernova remnant (SNR) with an X-ray luminosity in the range 0.15−3 keV that is almost 100 times fainter than the Crab Nebula. It hosts a pulsar wind nebula (PWN) with an X-ray delayed morphology. However, although PWNe are nebulae fed by the pulsar wind, no such object has been found at this SNR to date.

Recently, a team of astronomers led by Qian-Cheng Liu of Nanjing University investigated the X-ray point source in CTB 87, designated CXOU J201609.2+371110. They report that the use of fast radio pulses was detected in this source.

“We report the discovery of a radio pulsar (PSR J2016+3711) in the CTB 87 supernova remnant with a pulse value of ~10.8????, confirming the compact nature of the X-ray point source in CTB 87.” researchers wrote.

According to the article, PSR J2016+3711, located approximately 43,400 light-years away, has a rotation period of 50.8 milliseconds and a dispersion measure of approximately 428 pc/cm.³. The measured luminosity of the pulsar during rotation was 22 undecillion erg/s, and its characteristic age is estimated to be 11,100 years. Therefore, PSR J2016+3711 is the first pulsar detected by FAST at SNR.

The strength of the dipole magnetic field of the equatorial surface of PSR J2016+3711 was found to be 1.9 TG. The study also found that this pulsar’s radio pulse profile is narrow and does not have broad wings; This suggests that the radio beam emerging near the magnetic polar cap is narrow in nature or that the line of sight passes through a small portion of the wide beam. . .

Given that many pulsars also emit gamma rays, Liu’s team also analyzed data from NASA’s Fermi spacecraft to look for a possible gamma-ray pulsation from PSR J2016+3711. However, they were unable to detect a pulse of gamma radiation from this source. The researchers added that further observations are needed to definitively rule out PSR J2016+3711 as a gamma-ray emitter.

“Further follow-up radio observations over many years may be useful to obtain a more precise timing solution, which can then be used to narrow down the gamma-ray data and look for the pulse,” the study authors wrote.