Reasons most of the theoretical work has been done on deriving limitingĪnd/or averaged forms that can be easily included in the modeling ofĪstrophysical objects. Of the particle and photon spectra contribute significantly to theĬompton scattering in one given astrophysical situation. The exact cross section is quite complex and does not give any physical General formulae must be able to deal simultaneously with very small and very large energies. The energy of photons also spans a wide range: in the case of AGN for instance, it goes from low energy synchrotron photons (įor some sources). ), and to high energy cosmic rays (up to E > 100 TeV, i.e. The energy of particles spans from the veryĬold electrons of pulsars winds to the hot gas in the corona of X-ray The many varied applications result in different energy regimes for the Synchrotron self-Compton radiation that is thought to play a major roleįor example in AGN ( Tavecchio et al. More recently, much effort has been spent on high energy media in relativistic sources such as -rayīursts, AGN, and X-ray binaries. It is also responsible for the up-scattering of low energy photons from the microwave background radiation ( Zeldovich et al. Strong radiation field of X-ray or relativistic sources ( Levich & Syunyaev 1971). It was then used to model gases of high energy electrons in the Interacting with thermal stellar photons ( Follin 1947 Donahue 1951 Feenberg & Primakoff 1948,Įtc.). It was first introduced in the context of electron cosmic rays More than half a century, it has been applied to a large variety ofĪstrophysical situations, particularly in high energy, low density Key words: radiation mechanisms: general - plasmas - methods: numerical - galaxies: active - X-rays: binaries - X-rays: galaxiesĬompton scattering has become a major process in astrophysics, and for Expressions describing this combination are given. Section over the photon and particle distributions and a Fokker-PlanckĪpproximation. The most efficient way to solve the kineticĮquations is a method combining a direct integration of the cross Here allows for accurate and fast numerical evaluation for any photonĪnd electron energy. The regimes where existing cross sections can beĮvaluated numerically are given. Solve the kinetic equations using this cross section are studied. Investigated and compared to other formulae. An exact form of the isotropic Compton cross sectionįree of numerical cancellations is derived. The computation of the Compton scattering contribution to the timeĮvolution of interacting photon and particle populations. In this paper we investigate numerical issues related to Situations but are often not addressed properly.Īims. These can be severe in some astrophysical Section is simple in principle, its practical evaluation is often prone Although the numerical computation of the Compton cross Sophisticated codes that deal with all kinds of interactions in Point where they enable the direct use of exact formulae in ![]() Numerical capabilities have now developed to a Sections are often complex, and essentially asymptotic expressions haveīeen used in the past. It is well known and has been studied inĭetail for the past fifty years. Compton scattering is involved in manyĪstrophysical situations. Received 20 November 2007 / Accepted 7 July 2009Ĭontext. Rayonnements), Université de Toulouse, 9 Av. ![]() Numerical computation of isotropic Compton scattering Astronomical objects: linking to databases.Including author names using non-Roman alphabets.Suggested resources for more tips on language editing in the sciences Punctuation and style concerns regarding equations, figures, tables, and footnotes
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