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Scattering of electrons and positrons by molecules

Electrons

  • Cold plasmas - microelectronics, biomass, etching processes and chemical vapor deposition. The knowledge of the electron scattering cross sections by the gas molecules is important for the discharge modeling. More!
  • Astrophysics - Prebiotic molecules. Planetary atmospheres bombarded by photons and charged particles. Understanding atmospheric reentry physics in space programs. More!
  • Dissociative electron attachment - molecules of biological relevance. Low energy (secondary) electrons are responsible for breaking single- and double-strands in DNA. In this process, the electron is captured in some part of the molecule, forming a temporary negative ion (resonance), and begins the process of breaking a given chemical bond. This is a known process in electron-molecule collisions. More!
  • Metodologia - variational method to the scattering amplitude, the Schwinger multichannel method. More!

Positrons

  • Positron emission tomography (PET) - maging technique used in the diagnosis of tumors. A molecule containing a redioisotope (positron emitter) is placed in the patient's bloodstream and lodges in regions where there is high cellular activity (for example in a tumor). Through the annihilation of the electron-positron pair there is emission of gamma radiation, which is transformed into an image. More!
  • Theory - difficulties in the treatment of polarization and in the positronium formation channel. More!
  • Metodologia - variational method to the scattering amplitude, the Schwinger multichannel method. More!