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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

The photon of an incident laser pulse(pump) is, by a nonlinear optical crystal, divided into two lower-energy photons.  6, record 1, English, - nonlinear%20optical%20crystal

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 CONT

Une source laser émet une impulsion sur un cristal non linéaire, ce qui crée des paires de photons.  4, record 1, French, - cristal%20optique%20non%20lin%C3%A9aire

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 CONT

Detection efficiency. The intrinsic detection efficiency of any device operated in pulse mode is defined as the probability that a quantum of radiation incident on the detector will produce a recorded pulse. Especially for radiations of low intensity, a high detection efficiency is important to minimize the total time needed to record enough pulses for good statistical accuracy in the measurement. Detection efficiency is further subdivided into two types : total efficiency and peak efficiency. The total efficiency gives the probability that an incident quantum of radiation produces a pulse, regardless of size, from the detector. The peak efficiency is defined as the probability that the quantum will deposit all its initial energy in the detector. Since there are almost always ways in which the quantum may deposit only part of its energy and then escape from the detector, the total efficiency is generally larger than the peak efficiency.  1, record 2, English, - peak%20efficiency

Record number: 2, Textual support number: 1 OBS

This excerpt can be found in an article entitled “Radiation measurement” in the Britannica Encyclopaedia online.  2, record 2, English, - peak%20efficiency

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 CONT

Parmi toutes les particules émises par la source, une fraction seulement arrive dans le détecteur (en fonction de l’angle solide, des absorbants éventuels entre la source et le détecteur) et, parmi celles-ci, toutes n’intéragissent pas dans son volume utile (cas des photons en particulier). Pour accéder au nombre de particules émises par la source, il faut donc connaître l’efficacité du détecteur utilisé pour les particules détectées. On distingue : — l’efficacité absolue […] l’efficacité intrinsèque […] souvent on ne s’intéresse qu’à la surface des pics. On parle alors d’efficacité au pic (absolue ou intrinsèque).  1, record 2, French, - efficacit%C3%A9%20au%20pic

Record 2,  Textual support,  Spanish

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 CONT

Energy spectroscopy. For energy analysis the output current pulse from a PMT [photomultiplier tube] or from a semiconductor detector is often applied to a charge-sensitive preamplifier. The preamplifier produces a voltage pulse with a peak amplitude that is proportional to the total charge in the current pulse, which is proportional to the energy absorbed from the incident radiation. Amplifiers and filters are used to expand the range of the peak amplitude and to shape the signal from the preamplifier, a process that maximizes the signal-to-noise ratio for the system. For energy analysis the peak amplitude of the shaped pulse represents the information of interest. Discriminators and single-channel analyzers(SCA) can be used, following the signal shaping system, to determine the presence of certain energies of detected radiation. A discriminator produces an output logic pulse if it's input signal exceeds a preset threshold level. An SCA produces an output logic pulse if the peak amplitude of it's input signal falls within the energy window that is established with two preset threshold levels.  1, record 3, English, - energy%20spectroscopy

Record 3,  Textual support,  French

Record number: 3, Textual support number: 1 CONT

[Dans un détecteur fonctionnant en impulsion] La mesure de la hauteur d’impulsion fournit […] l’information énergie puisque celle-ci est proportionnelle aux charges créées dans le détecteur. Ce mode de fonctionnement est utilisé en spectroscopie d’énergie.  1, record 3, French, - spectroscopie%20d%26rsquo%3B%C3%A9nergie

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  French

Record 4,  Textual support,  Spanish