This work reevaluates the ion detection efficiency of the Jet Counter nanodosimeter working with low-pressure nitrogen. SIMION simulations were used to model the trajectories of ions during their extraction from the interaction chamber. The study examined the relationship between efficiency vs. extraction voltage, gas density, and temperature. The highest detection efficiency (approximately 60%) was achieved at a high extraction voltage and low temperature. The findings were then used as a parameter in the Monte Carlo modeling of the Jet Counter operations, and the results were compared with experimental results, showing satisfactory agreement.
Precise evaluation of a gamma-ray’s interaction position in scintillator detectors is important for their application in medical and industrial imaging. Two approaches can be pursued in achieving this goal: pixelated detectors or monolithic detectors coupled to pixelated readouts. Here, we present the design of a thin monolithic position-sensitive detector for low-energy gamma-rays. Two distinct position-evaluation methods were developed and assessed in terms of accuracy, precision, and imaging capabilities. An analytical model based on a curve-fitting procedure established a performance baseline. A neural network model showed superior performance, offering notable improvements in both accuracy and precision. Qualitative evaluation of the imaging results provided insights into the inherent advantages and limitations of both models. The results demonstrate the ability of a thin monolithic scintillator detector to generate images that significantly surpass the resolution of the readout array for low-energy gamma-ray imaging.
To make precision particle mass measurements in charged spectrometers detailed understanding of the influence of detector effects is critical. In this paper the influence of detector-related uncertainties on the determination of the parent particle mass in two-body decays is investigated. It is shown how the dependence of observed mass shifts on the sum and difference of the daughter particle momenta can be used to determine the physical causes of a bias more rigorously than the ad hoc rules that are often adopted. The approach is illustrated using the case of measuring the Λ hyperon mass. This observable is of interest because our current knowledge relies on information from a single experiment that has not been updated to account for changes in the value of the K_s^0 mass used for calibration. With the approach developed in the paper it shown that the LHCb experiment has the capability to make a measurement of the Λ mass with systematic uncertainties from the tracking system controlled to 0.7keV/c^2. This allows a total precision of 2.2keV/c^2 to be achieved, dominated by the knowledge of the K_s^0 mass used for calibration. This would improve the current knowledge of the Λ hyperon mass by a factor of three.
We report on a novel design for a HPGe-BGO pair spectrometer with the aim to enhance the performance of existing HPGe detectors for high-energy γ-rays. In addition, the BGO shield as a standalone detector allows for a use with the selective detection of positron annihilation. The compact geometry was optimized to use it with ELIADE, the HPGe array at VEGA (ELI-NP). We present the design, results from two commissioning runs with high-energy γ-rays and an outlook to future applications.
This paper presents a comprehensive overview of the Machine Detector Interface (MDI) design developed for the FCC-ee Feasibility Study. It highlights novel studies related to the lightweight interaction region, including a mechanical model of the vacuum chambers, integration of the vertex detector, the MDI alignment system, and assessments of machine-induced backgrounds. The small beam pipe radius and thickness, as well as the high power to be dissipated, require state-of-the-art mechanical design. The integration of all mechanical elements and detectors is challenging, necessitating careful studies to allow fulfilling conflicting requirements. The optimisation of the machine detector interface against formidable backgrounds is presented.
