Aspects of the subject technology relate to a system configured to apply a voltage setting to a sensor of a downhole tool. The system is configured to identify an active gain control model for a temperature-sensitive sensor for a downhole tool, receiving temperature data for the downhole tool, and apply a high voltage setting for the first sensor based on the temperature data and the active gain control model. The system is further configured to collect sensor data from the sensor operating in a wellbore using the high voltage setting and update the active gain control model based on the sensor data.

A method is provided for determining the dose rate {dot over (H)} of nuclear radiation field, namely a gamma radiation field, with a radiation detection system (RDS), comprising a scintillator, a photodetector, an amplifier and a pulse measurement electronics. The pulse measurement electronics includes a sampling analog to digital converter, where the nuclear radiation deposes at least some of its energy in the scintillator, thereby producing excited states in the scintillation material, with the excited states decaying thereafter under emission of photons with a decay time . Photons are absorbed by the photodetector under emission of electrons, those electrons forming a current pulse, said current pulse being amplified so that the resulting current signal can be processed further in order to determine the charge of the pulse measured.

The present disclosure describes gain stabilization techniques for scintillation devices which do not require use of an intrinsic reference radiation source. Reference light pulses are emitted into the scintillation device to obtain a signal having a given magnitude. The magnitude of the signal is compared to the magnitude of a reference signal computed as a function of temperature and a degradation factor. A gain adjustment is computed with causes the magnitude of the signal to match the target reference magnitude. The gain adjustment is then used to adjust the system gain so that subsequent output signal amplitudes, measured when energetic photons interact in the scintillator, always correspond to the same energy.

Embodiments are directed generally to an ionizing-radiation beamline monitoring system that includes a vacuum chamber structure with vacuum compatible flanges through which an incident ionizing-radiation beam enters the monitoring system. Embodiments further include at least one scintillator within the vacuum chamber structure that can be at least partially translated in the ionizing-radiation beam while oriented at an angle greater than 10 degrees to a normal of the incident ionizing-radiation beam, a machine vision camera coupled to a light-tight structure at atmospheric/ambient pressure that is attached to the vacuum chamber structure by a flange attached to a vacuum-tight viewport window with the camera and lens optical axis oriented at an angle of less than 80 degrees with respect to a normal of the scintillator, and at least one ultraviolet (UV) illumination source facing the scintillator in the ionizing-radiation beam for monitoring a scintillator stability comprising scintillator radiation damage.

Embodiments are directed generally to an ionizing-radiation beamline monitoring system that includes a vacuum chamber structure with vacuum compatible flanges through which an incident ionizing-radiation beam enters the monitoring system. Embodiments further include at least one scintillator within the vacuum chamber structure that can be at least partially translated in the ionizing-radiation beam while oriented at an angle greater than 10 degrees to a normal of the incident ionizing-radiation beam, a machine vision camera coupled to a light-tight structure at atmospheric/ambient pressure that is attached to the vacuum chamber structure by a flange attached to a vacuum-tight viewport window with the camera and lens optical axis oriented at an angle of less than 80 degrees with respect to a normal of the scintillator, and at least one ultraviolet (UV) illumination source facing the scintillator in the ionizing-radiation beam for monitoring a scintillator stability comprising scintillator radiation damage.

Disclosed is a spectrometry method including: for at least one ionizing-radiation energy E.sub.i, obtaining, for each energy E.sub.i, a curve of the number of photons detected, during a measurement interval, as a function of time, by spectrometer; b) for each curve, computing a ratio of the number of photons detected defined and separate time periods to obtain, for each ionizing-radiation energy E.sub.i, a number a.sub.i, or for each curve, acquiring one or more fitting parameters PAJ.sub.i by making a fit to the corresponding curve with a fitting function; and comparing each number a.sub.i or each fitting parameter or set of fitting parameters PAJ.sub.i with reference constants a.sub.i or, respectively, with reference fitting parameters PAJ.sub.i associated with reference energies E.sub.i to determine, for each number a.sub.i or each fitting parameter or set of fitting parameters PAJ.sub.i, reference energy E.sub.i of the ionizing radiation for which the corresponding curve was measured.

Disclosed is a spectrometry method including: for at least one ionizing-radiation energy E.sub.i, obtaining, for each energy E.sub.i, a curve of the number of photons detected, during a measurement interval, as a function of time, by spectrometer; b) for each curve, computing a ratio of the number of photons detected defined and separate time periods to obtain, for each ionizing-radiation energy E.sub.i, a number a.sub.i, or for each curve, acquiring one or more fitting parameters PAJ.sub.i by making a fit to the corresponding curve with a fitting function; and comparing each number a.sub.i or each fitting parameter or set of fitting parameters PAJ.sub.i with reference constants a.sub.i or, respectively, with reference fitting parameters PAJ.sub.i associated with reference energies E.sub.i to determine, for each number a.sub.i or each fitting parameter or set of fitting parameters PAJ.sub.i, reference energy E.sub.i of the ionizing radiation for which the corresponding curve was measured.

An online real-time correction method and system for a positron emission tomography (PET) detector. The method includes: acquiring a drifted channel number of a peak position of a full-energy peak in a drifted energy spectrum after a gain value of a PET detector system has changed and a ratio of a currently accumulated energy of each signal channel to a current total accumulated energy of all signal channels; substituting the above parameters, an initial channel number of the peak position of the full-energy peak in an initial energy spectrum and a ratio of an initially accumulated energy of each signal channel to a total initially accumulated energy of all of the signal channels in the PET detector system into a gain adjustment ratio calculation formula to calculate a gain adjustment ratio; and adjusting, according to the gain adjustment ratio, a gain value of the PET detector system.

An online real-time correction method and system for a positron emission tomography (PET) detector. The method includes: acquiring a drifted channel number of a peak position of a full-energy peak in a drifted energy spectrum after a gain value of a PET detector system has changed and a ratio of a currently accumulated energy of each signal channel to a current total accumulated energy of all signal channels; substituting the above parameters, an initial channel number of the peak position of the full-energy peak in an initial energy spectrum and a ratio of an initially accumulated energy of each signal channel to a total initially accumulated energy of all of the signal channels in the PET detector system into a gain adjustment ratio calculation formula to calculate a gain adjustment ratio; and adjusting, according to the gain adjustment ratio, a gain value of the PET detector system.

Provided is a radiation monitor, including: a radiation detection unit which includes a radiation detection element, the radiation detection element emitting light of a predetermined light emission wavelength; a light emission unit which emits light of a wavelength different from the light emission wavelength; a wavelength selection unit which passes the light of the light emission wavelength, and is set to a first mode to block the light from the light emission unit; an optical transmission line which transmits the light; a light detection unit which converts the light passing through the wavelength selection unit into an electric pulse; and a control unit which measures a count rate of the electric pulse, and determines whether at least the light emission unit is degraded on the basis of the count rate and a light intensity of the light emission unit.