Astronomy and Astrophysics – Astrophysics
Scientific paper
2002-12-03
Astrophys.J. 585 (2003) 955-974
Astronomy and Astrophysics
Astrophysics
20 pages, 12 figures, 1 table. Compared to v1 (and to the journal version), the bibliography updated and a typo corrected. Com
Scientific paper
10.1086/346150
We present an equation of state and radiative opacities for a strongly magnetized hydrogen plasma at magnetic fields B, temperatures T, and densities \rho typical for atmospheres of isolated neutron stars. The first- and second-order thermodynamic functions, monochromatic radiative opacities, and Rosseland mean opacities are calculated and tabulated, taking account of partial ionization, for 8x10^{11} G < B < 3x10^{13} G, 2x10^5 K < T < 10^7 K, and a wide range of \rho. We show that bound-bound and bound-free transitions give an important contribution to the opacities at T < (1-5)x10^6 K in the considered range of B in the outer neutron-star atmosphere layers, which may substantially modify the X-ray spectrum of a typical magnetized neutron star. In addition, we re-evaluate opacities due to free-free transitions, taking into account the motion of both interacting particles, electron and proton, in a strong magnetic field. Compared to the previous neutron-star atmosphere models, the free-free absorption is strongly suppressed at photon frequencies below the proton cyclotron frequency. The latter result holds for any field strength, which prompts a revision of existing theoretical models of X-ray spectra of magnetar atmospheres. Note added in v4: for free-free photoabsorption (Appendix B), equivalent but much simpler expressions are available in Appendix B of Potekhin & Lai, arXiv:astro-ph/0701285.
Chabrier Gilles
Potekhin Alexander Y.
No associations
LandOfFree
Equation of state and opacities for hydrogen atmospheres of neutron stars with strong magnetic fields does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Equation of state and opacities for hydrogen atmospheres of neutron stars with strong magnetic fields, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Equation of state and opacities for hydrogen atmospheres of neutron stars with strong magnetic fields will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-495687