• DOI:10.1093/mnras/stad274
• Corpus ID: 256080754

Evolutionary implications of a magnetar interpretation for GLEAM-X J162759.5-523504.3

@inproceedings{Suvorov2023EvolutionaryIO,
  title={Evolutionary implications of a magnetar interpretation for GLEAM-X J162759.5-523504.3},
  author={Arthur George Suvorov and Andrew Melatos},
  year={2023}
}

• A. Suvorov, A. Melatos
• Published 20 January 2023
• Physics

The radio pulsar GLEAM-X J162759.5–523504.3 has an extremely long spin period ( P = 1091 . 17 s), and yet seemingly continues to spin down rapidly ( ˙ P < 1 . 2 × 10 − 9 ss − 1 ). The magnetic field strength that is implied, if the source is a neutron star undergoing magnetic dipole braking, could exceed 10 16 G. This object may therefore be the most magnetised neutron star observed to date. In this paper, a critical analysis of a magnetar interpretation for the source is provided. (i) A minimum polar magnetic field strength of B ∼ 5 × 10 15 G appears to be necessary for the star to activate as a radio pulsar, based on conventional ‘death valley’ assumptions. (ii) Back-extrapolation from magnetic braking and Hall-plastic-Ohm decay suggests that a large angular momentum reservoir was available at birth to support intense field amplification. (iii) The observational absence of X-rays constrains the star’s field strength and age, as the competition between heating from field decay and Urca cooling implies a surface luminosity as a function of time. If the object is an isolated, young ( ∼ 10 kyr) magnetar with a present-day field strength of B (cid:38) 10 16 G, the upper limit ( ≈ 10 30 erg s − 1 ) set on its thermal luminosity suggests it is cooling via a direct Urca mechanism.