Abstract
The central problem in Quasielastic Neutron Spectroscopy (QNS) is the recovery of the scattering function S(Q,ω) or the recovery of the intermediate scattering function S̃(Q,t). Either of these two functions characterize the dynamics of the target under investigation. Time-of-Flight (TOF) spectroscopy aims at retrieving S(Q, ω) by performing a deconvolution involving the Point Spread Function (PSF) of the TOF instrument. The current TOF data analysis involves Least Squares Fitting (LSF) of strongly nonlinear parameters (e.g. linewidths) pertaining to phenomenological models. Neutron Spin-Echo (NSE) spectroscopy consists essentially in measuring S̃(Q,t) and subsequently Laplace transforming the intermediate scattering function to obtain a distribution of relaxation rates. This is a very ill-conditioned problem, for which LSF is known to yield very poor results. Now, in both the TOF and NSE cases, the data are expressed as linear forms of the sought scattering or distribution functions, for which the Maximum Entropy Method (MaxEnt) is known to yield a unique solution. This method was therefore used to analyze computer-simulated noisy data as well as real experimental data and it is shown to be quite successful for both TOF and NSE spectroscopies.
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© 1989 Springer Science+Business Media Dordrecht
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Papoular, R.J., Livesey, A.K. (1989). Quasielastic Neutron Scattering Data Evaluation Using the Maximum Entropy Method. In: Skilling, J. (eds) Maximum Entropy and Bayesian Methods. Fundamental Theories of Physics, vol 36. Springer, Dordrecht. https://doi.org/10.1007/978-94-015-7860-8_14
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DOI: https://doi.org/10.1007/978-94-015-7860-8_14
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