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تسجيل مستخدم جديدMagnetized Atmospheres around Accreting Neutron Stars
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S. Zane
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We present a detailed investigation of atmospheres around accreting neutron stars with high magnetic field ($Bgtrsim 10^{12}$ G) and low luminosity ($Llesssim 10^{33}$ erg/s). We compute the atmospheric structure, intensity and emergent spectrum for a plane-parallel, pure hydrogen medium by solving the transfer equations for the normal modes coupled to the hydrostatic and energy balance equations. The hard tail found in previous investigations for accreting, non-magnetic neutron stars with comparable luminosity is suppressed and the X-ray spectrum, although still harder than a blackbody at the star effective temperature, is nearly planckian in shape. Spectra from accreting atmospheres, both with high and low fields, are found to exhibit a significant excess at optical wavelengths above the Rayleigh-Jeans tail of the X-ray continuum.
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