NRS stands for nuclear resonant scattering and is a technique that is used to study the hyperfine transition in atoms. The first step in NRS is to excite the nucleus to a higher energy level, which is done with synchrotron radiation. These synchrotron radiation has a relative large energy spread, meaning that all the different hyperfine states will be occupied. These excited states then decay towards the ground state with a characteristic lifetime by emitting photons. These photons are captured by a detector over time and plotted on a so called time spectrum. However, since the difference in photon energies is very small, interference can occur. Using Fourier transformation, the energy spectrum can be deformed to a frequency spectrum. On this turn, from the frequency the hyperfine parameters can be deduces: hyperfine magnetic field, quadrupole splitting, isomer shift.