Cyclotron harmonics in opacities of isolated neutron star atmospheres

Abstract

Some of X-ray dim isolated neutron stars (XDINS) and central compact objects in supernova remnants (CCO) show absorption features in their thermal soft X-ray spectra. It has been hypothesized that these features could be due to the periodic peaks in free-free absorption opacities, caused by either Landau quantization of electron motion in magnetic fields B<10^{11} G or analogous quantization of ion motion in magnetic fields B>10^{13} G. Here, I review the physics behind cyclotron quantum harmonics in free-free photoabsorption, discuss different approximations for their calculation, and explain why the ion cyclotron harmonics (beyond the fundamental) cannot be observed.

12 pages, 5 figures. In v.5, a typo (missed sign factor) in Eq.(9) is fixed

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Cited by in corpus (15)

• Cyclotron lines in highly magnetized neutron stars
• Evolution of a buried magnetic field in the central compact object neutron stars
• Atmospheres and radiating surfaces of neutron stars
• Central Compact Objects in Supernova Remnants
• The Hidden Magnetic Field of The Young Neutron Star in Kesteven 79
• On the compactness of the isolated neutron star RX J0720.4-3125
• Constraining the Neutron Star Mass--Radius Relation and Dense Matter Equation of State with NICER. III. Model Description and Verification of Parameter Estimation Codes
• Phase resolved spectroscopic study of the isolated neutron star RBS 1223 (1RXS J130848.6+212708)
• Neutron stars - thermal emitters
• Low-magnetic-field magnetars
• Magnetized neutron star atmospheres: beyond cold plasma approximation
• Opacities and spectra of hydrogen atmospheres of moderately magnetized neutron stars
• A joint NICER and XMM-Newton view of the "Magnificent" thermally emitting X-ray Isolated Neutron Star RX J1605.3+3249
• QED Phenomena in an Ultrastrong Magnetic Field. II. Electron-Positron Scattering, $e^{\pm }$-Ion Scattering, and Relativistic Bremsstrahlung
• Mean opacities of a strongly magnetized high temperature plasma