Slow neutron time-of-flight spectrometry with a pseudo-random input signal

Calibration of the modulation transfer function of surface profilometers with binary pseudorandom test standards: expanding the application range to Fizeau interferometers and electron microscopes

“…[40][41][42] Alternatively, such sequences are referred to in literature as pseudonoise sequences or m-sequences. 40 Particular methods for generation of pseudorandom sequences 43,44 were developed in connection with communication and encryption processes, 45 acoustics, 46 and pseudorandom chopping of a beam in time-of-flight experiments with slow neutrons [47][48][49][50][51][52] and molecular beams. [53][54][55] The maximum duty cycle (relative number of 1's and 0's) of approximately 50% is obtained with a maximum-length pseudorandom sequence (MLPRS).…”

Calibration of the modulation transfer function of surface profilometers with binary pseudo-random test standards: expanding the application range

“…[25][26][27] Alternatively, such sequences are referred to as pseudo-noise sequences or m-sequences. 25 Particular methods for generation of pseudo-random sequences 28,29 were developed in connection with communication and encryption processes, 30 acoustics 31 , and pseudo-random chopping of a beam in time-of-flight experiments with slow neutrons [32][33][34][35][36][37] and molecular beams. [38][39][40] The maximum duty cycle (relative number of 1's and 0's) of approximately 50%…”

“…URAs are widely used as optimal mask patterns for coded aperture imaging techniques. 26 Analogous to the time-of-flight technique based on 1D BPR sequence chopping, [32][33][34][35][36][37][38][39][40] an imaging technique based on the 2D URAs allows one to obtain a better signal-to-noise ratio, keeping the high angular resolution characteristic of a single pinhole aperture. [42][43][44] Similar to the 1D BPR sequences, the URAs possess both high throughput (50%) and a delta-function-like cyclical autocorrelation function that corresponds to a flat 2D PSD spectrum.…”

Implementation of cross correlation for energy discrimination on the time-of-flight spectrometer CORELLI

“…One approach to achieve energy discrimination is to utilize the cross-correlation technique, whereby the incident beam is modulated in time in a pseudorandom way. This method was intensively investigated 50 years ago, mainly for steady-state sources and beam modulation achieved with mechanical choppers (Pá l et al, 1968;Skö ld, 1968;Von Jan & Scherm, 1970;Price & Skö ld, 1970;Gompf et al, 1968;Virjo, 1969), but was also considered for periodically modulated sources, such as long-pulse reactors (Matthes, 1968;Amadori & Hossfeld, 1972). The technique was later applied to the new generation of short-pulsed spallation neutron sources and a proof of the principle was carried out at the Intense Pulsed Neutron Source at Argonne National Laboratory (Crawford et al, 1986).…”