Abstract: A measuring system includes a detector having an optical waveguide including a primary dopant capable of transmuting, by neutron capture, into a stable secondary dopant that is less neutron-absorbent than the primary dopant, a moderation layer suitable for slowing down fast neutrons, and an analysis device connected to the detector. The analysis device is configured to inject, into the waveguide, an interrogation wave having a wavelength corresponding to an absorption peak of the secondary dopant, detect a response wave emitted by the waveguide, calculate, from the detected response wave, a piece of information relating to a concentration of secondary dopant in the waveguide, and, based on the information relating to the calculated concentration of secondary dopant, determine a fluence of fast neutrons during a predetermined secondary period.

Abstract: The invention relates to a scintillator for detecting neutrons and/or gamma photons, characterized in that it comprises a structure consisting of two undoped plastic materials for detecting neutrons and which contain different fluorescent complexes, a first plastic material containing at least one fluorescent complex able to produce a fluorescence light having a first relaxation time and the second plastic material containing at least one fluorescent complex able to produce a fluorescence light having a second relaxation time higher than the first relaxation time.

Abstract: A turbomachine casing including a substantially cylindrical wall and an annular one-piece acoustic insulation panel mounted inside the wall, the panel including an annular surface that is radially external opposite a radially internal annular surface of the wall, wherein the wall includes on its internal angular surface first projecting members which bear axially against second projecting members belonging to the external annular surface of the panel and which are fixed to these second members in a dismountable manner.

Abstract: A method for detecting a radioactive source moving on a linear path substantially parallel to an alignment of N detectors. The method includes: forming N×Nt pulse counting values Mi,t (i=1, 2, . . . , N and t=1, 2, . . . , Nt) from N×Nt detection signals delivered by the N detectors in the form of a succession over time of Nt sets of N signals simultaneously detected by the N detectors over a same duration ?t, a pulse counting value representing a number of pulses detected by a detector over a duration ?t; and computing, using a computer: a set of Nt correlation products Rt, a static mean R of the N×Nt counting values, a correlation condition for each correlation product Rt.

Abstract: A method and a device for compensation-based measurement of the alpha and/or beta radioactivity in a gamma background noise comprising a compensation probe comprises a first sensor allowing the measurement of the alpha and/or beta and gamma radioactivity and a second sensor not allowing the measurement of the alpha and/or beta radioactivity but allowing the measurement of the gamma radioactivity; wherein the sensors are arranged to be exposed substantially to the same gamma background noise; measurement biases being associated with the geometric arrangement of the sensors on account of the anisotropy of the gamma radiation; the measurement system determines the alpha and/or beta radioactivity by compensation comprising a subtraction between the measurement of alpha and/or beta and gamma radioactivity and the gamma measurement, the compensation minimizing the measurement biases associated with the geometric arrangement of the sensors.

Abstract: A device for processing signals detected by a set of n neutron detectors, the device including: n switches each including an input and an output, each switch receiving, on its input, a detected signal coming from a different detector, outputs of the n switches being linked to each other; and a clock generator including a clock circuit and a sequential counter controlled by the clock circuit and configured to deliver a plurality of pulse series, each pulse series of the plurality of pulse series constituting a control signal of a different switch, the pulses of any two pulse series of the plurality of pulse series being disjointed.

Abstract: A method for detecting a radioactive source moving on a linear path substantially parallel to an alignment of N detectors. The method includes: forming NxNt pulse counting values Mi,t (i=1, 2, . . . , N and t=1, 2, . . . , Nt) from NxNt detection signals delivered by the N detectors in the form of a succession over time of Nt sets of N signals simultaneously detected by the N detectors over a same duration ?t, a pulse counting value representing a number of pulses detected by a detector over a duration ?t; and computing, using a computer: a set of Nt correlation products Rt, a static mean R of the NxNt counting values, a correlation condition for each correlation product Rt.

Abstract: The invention relates to a scintillator for detecting neutrons and/or gamma photons, characterised in that it comprises a structure consisting of two undoped plastic materials for detecting neutrons and which contain different fluorescent complexes, a first plastic material containing at least one fluorescent complex able to produce a fluorescence light having a first relaxation time and the second plastic material containing at least one fluorescent complex able to produce a fluorescence light having a second relaxation time higher than the first relaxation time.

Abstract: A turbomachine casing including a substantially cylindrical wall and an annular one-piece acoustic insulation panel mounted inside the wall, the panel including an annular surface that is radially external opposite a radially internal annular surface of the wall, wherein the wall includes on its internal angular surface first projecting members which bear axially against second projecting members belonging to the external annular surface of the panel and which are fixed to these second members in a dismountable manner.

Abstract: A smoothing method associated with the on-line measurement of a signal output by an ionizing radiation detector comprising the following steps: detect pulses contained in successive samples of said signal, count the numbers Ni of pulses detected, apply non-destructive filtering to said signal using a variable detection threshold, and apply adaptive smoothing to the filtered signal using non-linear processing as a function of the state of change of said signal so as to obtain a smoothed count rate for said pulses.