SIMBAD references

2020MNRAS.494.3611K - Mon. Not. R. Astron. Soc., 494, 3611-3615 (2020)

Pulsing and non-pulsing ULXs: the iceberg emerges.


Abstract (from CDS):

We show that ultraluminous X-ray sources (ULXs) with coherent X-ray pulsing (PULXs) probably have neutron-star spin axes significantly misaligned from their central accretion discs. Scattering in the funnels collimating their emission and producing their apparent super-Eddington luminosities is the most likely origin of the observed correlation between pulse fraction and X-ray photon energy. Pulsing is suppressed in systems with the neutron-star spin closely aligned to the inner disc, explaining why some ULXs show cyclotron features indicating strong magnetic fields, but do not pulse. We suggest that alignment (or conceivably, field suppression through accretion) generally occurs within a fairly short fraction of the ULX lifetime, so that most neutron-star ULXs become unpulsed. As a result we further suggest that almost all ULXs actually have neutron-star accretors, rather than black holes or white dwarfs, reflecting their progenitor high-mass X-ray binary and supersoft X-ray source populations.

Abstract Copyright: © 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society

Journal keyword(s): accretion, accretion discs - black hole physics - binaries: close - pulsars: general - X-rays: binaries

Simbad objects: 13

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2020MNRAS.494.3611K and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact