China's Insight-HXMT Records Strongest Magnetic Field in Universe, Measuring Over 1.6 Billion Tesla

In a groundbreaking discovery, scientists have recorded the strongest ever magnetic field in the universe. It was recently measured by the Chinese astronomy satellite Insight-HXTM, which is said to have broken its own record of detecting the strongest magnetic fields.

When it comes to magnetic fields, neutron stars are said to posses the strongest ones in the universe. Scientists usually measure the power of these fields by observing the cyclotron absorption lines in their X-ray energy spectra.

Previously, the strongest magnetic field was detected in 2020, which had a magnitude of around 1 billion Tesla. Following this, the world record for the strongest magnetic field and the highest energy cyclotron were revised significantly.

Now, the Insight-HXTM team has spotted a cyclotron absorption line in the neutron star X-ray binary Swift J0243.6+6124 having the energy of 146 keV. This was corresponding to a surface magnetic field with a magnitude of more than 1.6 billion Tesla.

The discovery was made jointly by the Key Laboratory for Particle Astrophysics at the Institute of High Energy Physics (IHEP) of the Chinese Academy of Sciences and the Institute for Astronomy and Astrophysics, Kepler Center for Astro and Particle Physics, University of Tubingen (IAAT).

As per the findings, published in Astrophysical Journal Letters, the outburst of Swift J0243.6+6124 was observed in detail and its cyclotron absorption lines were discovered by the Insight-HXMT. The Swift J0243.6+6124 is the Milky Way galaxy's first ultraluminous X-ray pulsar.

The cyclotron line had energy up to 146 keV that corresponds to a surface magnetic field of more than 1.6 billion Tesla. The magnetic field detected is not only the strongest to be directly measured in the universe to date but also the first detection of the electron cyclotron absorption line in an ultraluminous X-ray source.

The findings serve as concrete evidence that the magnetic field of a neutron star is more complex than that of the traditional symmetric dipole field. In addition, it also offers the measurement of the nonsymmetric component of a neutron star's magnetic field for the first time.