Jean-Francois Clergeau

arXiv2013

Investigation of gamma-ray sensitivity of neutron detectors based on thin converter films

Currently, many detector technologies for thermal neutron detection are in development in order to lower the demand for the rare 3He gas. Gas detectors with solid thin film neutron converters readout by gas proportional counter method have been proposed as an appropriate choice for applications where large area coverage is necessary. In this paper, we investigate the probability for gamma-rays to generate a false count in a neutron measurement. Simulated results are compared to measurement with a 10B thin film prototype and a 3He detector. It is demonstrated that equal gamma-ray rejection to that of 3He tubes is achieved with the new technology. The arguments and results presented here are also applicable to gas detectors with converters other than solid 10B layers, such as 6Li layers and 10BF3 gas.

physics.ins-det↗

arXiv2006

An Electrostatic Lens to Reduce Parallax in Banana Gas Detectors

Cylindrical "banana" gas detectors are often used in fixed-target experiments, because they are free of parallax effects in the equatorial plane. However, there is a growing demand to increase the height of these detectors in order to be more efficient or to cover more solid angle, and hence a parallax effect starts to limit the resolution in that direction. In this paper we propose a hardware correction for this problem which reduces the parallax error thanks to an applied potential on the front window that makes the electrostatic field lines radially pointing to the interaction point at the entrance window. A detailed analytical analysis of the solution is also presented.

physics.ins-det↗