Population synthesis of ultraluminous X-ray sources with magnetised neutron stars

Abstract

A model of population of ultraluminous X-ray sources with magnetised neutron stars (NULX) in a spiral galaxy with the star formation history similar to that in the thin disc of Milky Way is computed using a hybrid approach. First, applying analytical approximations (code BSE) we construct the ensemble of close binaries (CBS) which can be potential precursors of NULX. Next, evolution with accretion onto magnetised neutron stars (NS) is computed by the evolutionary code MESA. Accretion rate onto NS and X-ray luminosity are calculated for the models of sub- and supercritical discs and for the discs with advection. During accretion onto magnetised NS, super-Eddington luminosity $L_{\mathrm{X}}>10^{38}$ erg~s${}^{-1}$ is attained already at the subcritical stage, when the energy release at the inner boundary of the disc defined by the NS magnetosphere is sub-Eddington. It is shown that standard evolution of CBS with an account of the peculiarities specific for accretion onto magnetised NS allows us to explain quantitatively observed characteristics of NULX (X-ray luminosities, NS spin periods, orbital periods and masses of visual components) without additional model assumptions on the collimation of X-ray emission from NS with high observed super-Eddington luminosity. In a model galaxy with star formation rate 3--5 $M_{\odot }\mathrm{y}{\mathrm{r}}^{-1}$ there can exist several NULX. Discovery of a powerful wind from NULX with $L_{\mathrm{X}}\sim 10^{41}$ erg~s${}^{-1}$ would be a signature of super-Eddington accretion onto magnetised NS.

29 pages, 11 figures. Published in Astronomy Letters, v. 46, Issue 10, pp. 658-676, 2020 (doi:10.1134/S1063773720100084)

References in corpus (29)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Binary interaction dominates the evolution of massive stars
• An Ultraluminous X-ray Source Powered by An Accreting Neutron Star
• An accreting pulsar with extreme properties drives an ultraluminous x-ray source in NGC 5907
• Discovery of a 0.42-s pulsar in the ultraluminous X-ray source NGC 7793 P13
• A mass of less than 15 solar masses for the black hole in an ultraluminous X-ray source
• Masses, Beaming and Eddington Ratios in Ultraluminous X-ray Sources
• The discovery of weak coherent pulsations in the ultraluminous X-ray source NGC 1313 X-2
• Population Synthesis of Cataclysmic Variables: I. Inclusion of Detailed Nuclear Evolution
• Pulsing ULXs: tip of the iceberg?
• Winds from stripped low-mass Helium stars and Wolf-Rayet stars
• Ultra-luminous X-ray sources and neutron-star-black-hole mergers from very massive close binaries at low metallicity
• ULX spectra revisited: Accreting, highly magnetized neutron stars as the engines of ultraluminous X-ray sources
• A census of ultraluminous X-ray sources in the local Universe
• The ultraluminous X-ray source NGC 1313 X-2 - Its optical counterpart and environment
• A new, clean catalogue of extragalactic non-nuclear X-ray sources in nearby galaxies
• No magnetars in ULXs
• Super-Eddington accretion discs with advection and outflows around magnetized neutron stars
• M51 ULX-7: super-orbital periodicity and constraints on the neutron star magnetic field
• A Population of Ultraluminous X-ray Sources with An Accreting Neutron Star
• On the Formation of Ultraluminous X-ray Sources with Neutron Star Accretors: the Case of M82 X-2
• Super-Eddington accretion onto the Galactic ultraluminous X-ray pulsar Swift J0243.6+6124
• Next generation population synthesis of accreting white dwarfs: I. Hybrid calculations using BSE + MESA
• Insight-HXMT observations of Swift J0243.6+6124 during its 2017-2018 outburst
• Bright end of the luminosity function of high-mass X-ray binaries: contributions of hard, soft and supersoft sources
• CG X-1: an eclipsing Wolf-Rayet ULX in the Circinus galaxy
• Mass ratio in SS433 revisited
• Chandra and XMM-Newton discovery of the transient X-ray pulsar in the nearby spiral galaxy NGC2403
• The origin of the bimodal luminosity distribution of ultraluminous X-ray pulsars

Cited by in corpus (10)

• Ultraluminous X-ray sources
• Statistical study of a large and cleaned sample of ultraluminous and hyperluminous X-ray sources
• Formation of Mass-gap Black Holes from Neutron Star X-ray Binaries with Super-Eddington Accretion
• Populations of Neutron Star Ultraluminous X-ray Sources: Mind your b's and B's
• Bright X-ray pulsars as sources of MeV neutrinos in the sky
• Propeller states in locally super-critical ULXs
• High-Mass X-Ray Binaries with Be Donors as Ultraluminous X-Ray Sources
• Characteristics and evolution of Be-type high mass X-ray binaries as potential Ultraluminous X-ray Sources
• Populations of ultraluminous X-ray sources in galaxies: origin and evolution
• A Long-term Study of Ultraluminous X-ray Sources in NGC 891