Photon energy dependent studies

Recently, a group in the United Kingdom started to study the effect of vacuum UV photons using the Daresbury synchrotron facility. They measured the yields of ssb and dsb in plasmid DNA, and proposed that the mechanism or a precursor to produce both types of strand breaks are common, because the photon energy dependence is similar for both types, although the absolute yield differed by 50-fold [17]. They confirmed that double... 

Data on the photon energy dependence of the biological effect has been accumulated fairly well with strand-break induction in plasmid DNA, and with an inactivation of the spore of a bacterium. These studies gave us many clues to understand the induction mechanism of biological effects in cells. However, for a complete understanding, research in the following areas should be highly promoted. 

The interaction of a photon with an atom changes the structure of the atom, and the photon-energy-dependent change in the observables is called the dynamics in the photon-atom interaction. Therefore, in the present context of the study of photoionization processes using electron spectrometry and synchrotron radiation, the observations that can be made on the emitted electrons are all studies of dynamical properties. In the light of the foregoing discussion on the forces in the atom and the transition operator it can be concluded that photoprocesses in atoms provide a unique opportunity for fundamental investigations which explore the dynamics of many-body effects, because both the forces and the interaction... 

Stars and radioactivity induced by photons Energy dependence. From studies with... 

Davis et al. reported the successful etching of PTFE using single-photon energies in the quartz UV (308 nm and a pulse duration of 25 ns) by sensitizing the fluoropolymer with polyimide. 72 The number of pulses varied depending on fluence and material composition in order to achieve ablated features whose depths were reproducible as measured by a stylus-type profilometer. The pulse repetition rate was on the order of about 200 Hz. In that study, dopant levels... 

G(X) and quantum yield of the product used for the calculation, respectively. Two possible sources of errors should be mentioned. One is the energy dependence of the photodecomposition. In order to obtain intrinsic yield should be measured at photon energies as close as possible to the absorption onset, or appropriate corrections should be used [154,155]. Both photon emission and photodecomposition studies show that the energy dependence is more severe for the smaller molecules than for the larger ones. Therefore, G(Si) for the larger molecules can be estimated with higher accuracy. The second source of error is that X may not solely form in Si molecule transformation. 

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