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Spherical Accretion onto Neutron Stars Revisited: Are Hot Solutions Possible ?

Roberto Turolla·Luca Zampieri·Monica Colpi·Aldo Treves
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Abstract

Stationary, spherical accretion onto an unmagnetized neutron star is here reconsidered on the wake of the seminal paper by Zel'dovich \& Shakura (1969). It is found that new ``hot'' solutions may exist for a wide range of luminosities. These solutions are characterized by a high temperature, $10^{9}÷10^{11}$ K, and arise from a stationary equilibrium model where the dominant radiative mechanisms are multiple Compton scattering and bremsstrahlung emission. For low luminosities, $\mincir 10^{-2} \ L_{E}$, only the ``cold'' (à la Zel'dovich and Shakura) solution is present.

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Roberto Turolla, Luca Zampieri, Monica Colpi, Aldo Treves. 1994-02-21. Spherical Accretion onto Neutron Stars Revisited: Are Hot Solutions Possible ?. https://doi.org/10.1086/187333

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