Filipe Costa

PhD Student
PhD Programme: Radiation Biology and Biophysics

Research Areas

PhD Thesis: “Dissociative processes induced by electron and radical impact with biologically " (2016-2020)

Adviser: Prof. Doutor Gustavo García

Absorbed dose is the reference magnitude for biomedical applications of radiation. It is proportional to the number of electron-ion pairs induced when living tissue (commonly assumed as water) is exposed to ionising radiation sources. However not all the ionising processes have the same relevance in the biological effect of the radiation. Dissociative processes generate neutral and ionic radicals which can damage essential molecules for living tissue as DNA and RNA components. This work intends to study the molecular dissociation induced electron and radical interactions with constituent molecules of DNA and RNA and similar molecular structures as purine, pyrimidine and pyridazine. Dissociative ionisation by electron impact will be determined by time of flight (TOF) analysis in crossed beam experiments. Total interaction cross section of positive and negative molecular fragments H+, H-, O+, O- with these molecules will be measured by using a transmission beam technique. Complementary energy loss spectra will be also obtained in order to obtain representative data collections for modelling purposes.