Simulation Project tripleaxis: Energy resolution

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Investigate the energy resolution of your spectrometer by performing a scan of the energy transfer. Vary \(E_{\rm i}\) by moving TTM/OMM, keeping all other angles constant. Use 5.0 meV for \(E_{\rm f}\) and a non-zero value for TT. Plot the simulated intensity (e.g. E-monitor with only one channel) as a function of \(\hbar\omega\) and find the energy resolution (FWHM of the peak) using MatLab.

Where would you place the Be filter in such an experiment?

Hint

Remember to stretch the lambda interval in the source to allow for the change in \(E_{\rm i}\). If it is a help, you can safely assume that the optimal curvature does not change significantly over the scan. Multiple McStas simulations can be run from the command line by typing a series of mcrun commands into a file and the excecuting the file by the command source ./<filename>. The syntax for the McStas command line mcrun is given in the manual.