A method to measure the angular differential cross section of (n, α) reactions using gridded ionization chamber and gas sample

AbstraktAbstract

A method to measure the angular differential cross section of (n, α) reactions using gridded ionization chamber (GIC) and gas sample was established. The anode signal rise time is used to get the projection length of the track in the direction of the electric field (related to the α emission angle). The anode signal amplitude is used to distinguish the events with the same anode signal rise time but different α emission angles because of the PHD (pulse height defect) effect. Using this method, the angular differential cross sections of the 16O(n, α0)13C reaction at 10.45 MeV were measured based on the HI-13 tandem accelerator of China Institute of Atomic Energy (CIAE). The GIC was used as the charged particle detector, with working gas of 3.0 atm Kr+4.0%CO2. The oxygen atoms in the CO2 were used as the sample. Anode signal amplitude vs the anode signal rise time two-dimensional spectrum was used in this method to determine the count of the 16O(n, α0)13C reaction events. A 238U3O8 sample inside the GIC was used to determine the neutron fluences and an EJ-309 scintillation detector was placed on the beam line to measure the neutron energy spectra to correct the events induced by the low-energy neutrons.

A method to measure the angular differential cross section of (n, α) reactions using gridded ionization chamber (GIC) and gas sample was established. The anode signal rise time is used to get the projection length of the track in the direction of the electric field (related to the α emission angle). The anode signal amplitude is used to distinguish the events with the same anode signal rise time but different α emission angles because of the PHD (pulse height defect) effect. Using this method, the angular differential cross sections of the 16O(n, α0)13C reaction at 10.45 MeV were measured based on the HI-13 tandem accelerator of China Institute of Atomic Energy (CIAE). The GIC was used as the charged particle detector, with working gas of 3.0 atm Kr+4.0%CO2. The oxygen atoms in the CO2 were used as the sample. Anode signal amplitude vs the anode signal rise time two-dimensional spectrum was used in this method to determine the count of the 16O(n, α0)13C reaction events. A 238U3O8 sample inside the GIC was used to determine the neutron fluences and an EJ-309 scintillation detector was placed on the beam line to measure the neutron energy spectra to correct the events induced by the low-energy neutrons.