Magnetar

Artist's conception of a powerful magnetar in a star cluster

A magnetar is a type of neutron star with an extremely powerful magnetic field (~109 to 1011 T, ~1013 to 1015 G).[1] The magnetic-field decay powers the emission of high-energy electromagnetic radiation, particularly X-rays and gamma rays.[2]

The existence of magnetars was proposed in 1992 by Robert Duncan and Christopher Thompson.[3] Their proposal sought to explain the properties of transient sources of gamma rays, now known as soft gamma repeaters (SGRs).[4][5] Over the following decade, the magnetar hypothesis became widely accepted, and was extended to explain anomalous X-ray pulsars (AXPs). As of July 2021, 24 magnetars have been confirmed.[6]

It has been suggested that magnetars are the source of fast radio bursts (FRB), in particular as a result of findings in 2020 by scientists using the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope.[7]

  1. ^ Kaspi, Victoria M.; Beloborodov, Andrei M. (2017). "Magnetars". Annual Review of Astronomy and Astrophysics. 55 (1): 261–301. arXiv:1703.00068. Bibcode:2017ARA&A..55..261K. doi:10.1146/annurev-astro-081915-023329.
  2. ^ Ward; Brownlee, p.286
  3. ^ Duncan, Robert C.; Thompson, Christopher (1992). "Formation of Very Strongly Magnetized Neutron Stars: Implications for Gamma-Ray Bursts". Astrophysical Journal Letters. 392: L9. Bibcode:1992ApJ...392L...9D. doi:10.1086/186413.
  4. ^ Cite error: The named reference journal was invoked but never defined (see the help page).
  5. ^ Thompson, Christopher; Duncan, Robert C. (July 1995). "The soft gamma repeaters as very strongly magnetized neutron stars - I. radiative mechanisms for outbursts". Monthly Notices of the Royal Astronomical Society. 275 (2): 255–300. Bibcode:1995MNRAS.275..255T. doi:10.1093/mnras/275.2.255.
  6. ^ Cite error: The named reference mcgill was invoked but never defined (see the help page).
  7. ^ Starr, Michelle (1 June 2020). "Astronomers Just Narrowed Down The Source of Those Powerful Radio Signals From Space". ScienceAlert.com. Retrieved 2 June 2020.