Evenson P.Clem J.Mangeard P.S.Nuntiyakul W.Ruffolo D.Seripienlert A.Mahidol University2024-12-232024-12-232024-09-27Proceedings of Science Vol.444 (2024)https://repository.li.mahidol.ac.th/handle/20.500.14594/102491The BP28 BF3 proportional tube was specifically designed for the NM64 neutron monitor introduced to the cosmic ray community in 1964. This neutron monitor design has remained the standard to date. In 1999, during the construction phase of the Space-Ship Earth NM64 monitors, it was realized the cost of a highly efficient 3He filled proportional tube, manufactured by the LND company, was less than a BP28, and provided nearly the same sensitivity as a BP28 in a NM64 structure. Consequently, the LND 3He tubes were chosen for the new SSE NM64 stations, and to upgrade stations Thule, South Pole and Newark. Unfortunately, since then, the price of the 3He tubes has significantly increased, due to the rising cost of He3, and the original BP28 tubes are no longer manufactured. Consequently, we have embarked on an investigation to evaluate a suitable BF3 proportional tube to replace the original BP28. The investigation includes characterization of key performance parameters of two slightly different proportional tubes, with different anode wire and cathode tube thicknesses, while maintaining the same tube geometry, gas volume, pressure and purity. In this paper we present measurements and discuss the results.MultidisciplinaryConference PaperSCOPUS2-s2.0-8521226013818248039