We suggest that the recently discovered, enigmatic pulsar with a period of 18.18 minutes, GLEAM-X J162759.5-523504.3, is most likely a hot subdwarf (proto white dwarf). A magnetic dipole model explains the observed period and period-derivative for a highly magnetized (∼108G), hot subdwarf of typical mass ∼0.5M⊙ and radius ∼0.3R⊙, and an age of ∼3×104yr. The subdwarf spin is close to its breakup speed and its spindown luminosity is near its Eddington limit, likely as a result of accretion from a companion.
@article{arxiv.2202.04949,
title = {A Hot Subdwarf Model for the 18.18 Minute Pulsar GLEAM-X},
author = {Abraham Loeb and Dan Maoz},
journal= {arXiv preprint arXiv:2202.04949},
year = {2022}
}
Comments
4 pages, accepted for publication in Research Notes of the American Astronomical Society