New measurement record for the strongest known universe magnetic field

An item that rotates inside a rotating neutron star is known as a “pulsar” or GRO J1008-5. Jocelyn Bell made observations of a 1.33-second regular radio pulse before making the initial discovery. The item was given the ironic designation LGM1 after it was determined that the pulses did not originate from humans (“Little Green Men”). A beam of energy is projected along the magnet poles of a rotating neutron star. Similar to the beams of a rotating lighthouse, the beam sweeps across space as it spins. Depending on the star’s position, these beams might cover the whole field of view for Earth. They have the ability to generate an energy “pulse” with each star spin. Neutron stars are the most powerful galaxies. It is possible to establish their surface magnetic field from X-ray energy data. Their spectra also exhibit the cyclotron spectral lines. Swift J0243.6+6124 is a neutron-star X-ray binary that has just been discovered by Insight HXMT. It contains a cyclotron-absorbing band with a value of 146 keV.

A surface magnetism of far more than 1.6 trillion Tesla would be the equivalent. The measurements of that field as well as the new world records for the largest cyclotron amplification factor in the world have indeed been established. At a flux density of roughly 1 billion Tesla, this measurement was made.

These observations, which were jointly acquired by the University of High Energy Physics of the Chinese Academy of Sciences’ Key Laboratory for Particle Astrophysics and the Institution for Astrophysics and Astronomy of the University of Tubingen have been published in the Astrophysical Journal. The paper’s founders were Prof. Zhang Shuangnan and Prof. Zhang Shuangda from IHEP. The University of Tubingen’s Professor Andrea Santangelo (and Dr. Victor Doroshenko) were key to this discovery.

A neutral star and its companion help compensate for a neutron binary number system with X-ray neutron stars. Gas from the companion stars falls towards the neutron star under the intense gravitational pressure of the neutron star, creating an accretion disc. Until it reaches the neutron star’s surface, the plasma that forms the accretion circle will drop following magnetic lines. Here, a strong X-ray wave is generated. The neutron star’s rotation causes these recurring X-ray radiation pulses.

This object’s X-ray radiation bands contain an absorption structure, according to numerous observations. The cyclotron absorption lines are these. Resonant dispersion and electron movement along large magnet fields are expected to be the main causes of this phenomenon. The effect of the magnetic field on the surface of the neutron star is highly related to the energy of this absorption structure.

Ultra-luminous X-ray pulsars are an entity class whose X-ray luminosity is considerably higher than that of classical X-ray absorption pulsars. They have already been found in various distant galaxies from the Night Sky. Although there is no concrete proof, astronomers have theorized that their Pulsars have strong magnetic fields.

The cyclotron absorbing line of Swift J0243.6+6124, the Milky Way’s first ultra-luminous X-ray pulsar, was definitely discovered by Insight-HXMT via extensive and broad-band studies of its outburst. With a detection significance of almost 10 times the standard deviation, this line revealed energy up to 146 keV, which is equal to a surface magnetic field of much more than a billion Tesla. The neutron star’s surface magnetic field can be directly measured due to the discovery of the first electron cyclotron amplification factor in an ultra-luminous X-ray source, making it not only the known universe’s strongest magnetic force to date.

Some hypotheses suggest that the surface magnetic fields of neutron stars have complicated structures. They might consist of dipole or multipole fields that only have an impact on the neutron star’s direct proximity. However, only the dipole fields have been included in indirect estimates of neutron star magnetic fields in the past.

The Horizons team discovered in 2020 that a neutron star inside the X-ray binary star system GRO J1008-57 once benefitted from a 90 keV cyclotron that was comparable to a global magnetism of one billion Tesla. For the accurate observation of the strongest magnetic field in the solar program at the moment, this discovery set a new world record. Later, Insight-HXMT found an unexplored cyclotron absorption line at 1A 0535+262 from a different neutron star, with a peak power of about 100 keV. Insight-HXMT already has shown that it has remarkable freedom to discover the energy range by smashing its own records for cyclotron absorption line discoveries.

Prof. LI Taipei and Prof. Wu Mei suggested the idea for Insight HXMT at IHEP in 1993, and it was officially deployed on June 15, 2017. Its system is achieved by the China National Space Council, CAS, and CAS. IHEP was responsible for this mission’s scientific study, ground sections, and satellite payloads. Creating the satellite system was the task of the China Institute of Space Travel. The ground segment and payload were both developed with help from Tsinghua University. Beijing Normal University and the NASA Space Science Center collaborated on the mission. The calibration of Insight HXMT’s detectors is made possible by Max Planck Institute for extra-terrestrial Physics.