Beamed Emission from a Neutron-star ULX in a GRRMHD Simulation
David Abarca, Kyle Parfrey, Włodek Kluźniak
Abstract
Abstract We perform a global 2.5D general-relativistic radiation magnetohydrodynamic simulation of supercritical accretion onto a neutron star with a 2 × 10 10 G dipolar magnetic field, as a model of a neutron-star-powered ultraluminous X-ray source (ULX). We compute a lower limit on the total luminosity of ∼2.5 L Edd , and find the radiation to be highly beamed by the accretion disk outflows. The apparent isotropic luminosity, which is a function of the viewing angle, reaches a maximum above 100 L Edd , consistent with the luminosities observed in ULXs.
Topics & Concepts
PhysicsAstrophysicsNeutron starMagnetohydrodynamic driveLuminosityRadiationBlack-body radiationAccretion (finance)IsotropyAccretion discDipoleLimit (mathematics)Magnetic fieldComputational physicsPhotonMagnetic dipoleNeutronFunction (biology)OpticsSupercritical fluidMagnetic momentMagnetohydrodynamicsSynchrotron radiationAstronomyLuminosity functionMagnetic monopoleAstrophysical Phenomena and ObservationsAstrophysics and Cosmic PhenomenaAstrophysics and Star Formation Studies