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Yes of course. There are techniques which allow astronomers and astrophysicists to calculate these quantities quite efficiently and correctly and it depends on the spectrum, the luminosity and the distance of the star. In fact, from just the luminosity and the distance, one can compute almost everything important about the star including its age, ...


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As Arthur Desrosiers mentions, there are 3 main interactions which govern the deposition of energy into the detector. These, however, are not the reason for the effect you are describing. The increase in FWHM is due to the statistical fluctuation of electron-hole pairs created and their contribution to a small current created in the detector, converted to a ...


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The gamma photon energy is a function of the energy levels in the nucleus. There is some uncertainty in these levels. However, the data that you present in the chart is the amount of energy deposited in a detector, where the uncertainty is determined by the uncertainty in the interaction of the photon with the material of the detector and the processing of ...


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If light of intensity $I_0$ is incident on a sample or a dielectric interface, at the boundary the following equation will hold: $$I_0 = I_T + I_R + I_A$$ where $I_T$ is the transmitted light, $I_R$ is the reflected light and $I_A$ is the fraction of light which is absorbed by be medium. The absorption is usually calculated from the Beer–Lambert law $$\phi_T ...


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The rule against $0\rightarrow0$ transitions is the strongest of all selection rules on spectroscopy. It has a simple explanation. The photon has $J=1$, and you cannot remove one unit of angular momentum from a system with $J=0$ and still have $J=0$. Such transitions then typically have to involve more than one photon. That makes them difficult to ...



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