Frontiers in Astronomy and Space Sciences (Jan 2024)

The high energy X-ray probe (HEX-P): magnetars and other isolated neutron stars

  • J. A. J. Alford,
  • G. A. Younes,
  • Z. Wadiasingh,
  • Z. Wadiasingh,
  • Z. Wadiasingh,
  • M. Abdelmaguid,
  • H. An,
  • M. Bachetti,
  • M. G. Baring,
  • A. Beloborodov,
  • A. Y. Chen,
  • T. Enoto,
  • J. A. García,
  • J. D. Gelfand,
  • E. V. Gotthelf,
  • A. K. Harding,
  • C-P. Hu,
  • A. D. Jaodand,
  • V. Kaspi,
  • C. Kim,
  • C. Kouveliotou,
  • L. Kuiper,
  • K. Mori,
  • M. Nynka,
  • J. Park,
  • D. Stern,
  • J. Valverde,
  • D. J. Walton

DOI
https://doi.org/10.3389/fspas.2023.1294449
Journal volume & issue
Vol. 10

Abstract

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The hard X-ray emission from magnetars and other isolated neutron stars remains under-explored. An instrument with higher sensitivity to hard X-rays is critical to understanding the physics of neutron star magnetospheres and also the relationship between magnetars and Fast Radio Bursts (FRBs). High sensitivity to hard X-rays is required to determine the number of magnetars with hard X-ray tails, and to track transient non-thermal emission from these sources for years post-outburst. This sensitivity would also enable previously impossible studies of the faint non-thermal emission from middle-aged rotation-powered pulsars (RPPs), and detailed phase-resolved spectroscopic studies of younger, bright RPPs. The High Energy X-ray Probe (HEX-P) is a probe-class mission concept that will combine high spatial resolution X-ray imaging (<5 arcsec half-power diameter (HPD) at 0.2–25 keV) and broad spectral coverage (0.2–80 keV) with a sensitivity superior to current facilities (including XMM-Newton and NuSTAR). HEX-P has the required timing resolution to perform follow-up observations of sources identified by other facilities and positively identify candidate pulsating neutron stars. Here we discuss how HEX-P is ideally suited to address important questions about the physics of magnetars and other isolated neutron stars.

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