title: Absolute calibration of neutron detectors on the C-2U advanced beam-driven FRC.
abstract: In the C-2U fusion energy experiment, high power neutral beam injection creates a large fast ion population that sustains a field-reversed configuration (FRC) plasma. The diagnosis of the fast ion pressure in these high-performance plasmas is therefore critical, and the measurement of the flux of neutrons from the deuterium-deuterium (D-D) fusion reaction is well suited to the task. Here we describe the absolute, in situ calibration of scintillation neutron detectors via two independent methods: firing deuterium beams into a high density gas target and calibration with a 2 × 107n/s AmBe source. The practical issues of each method are discussed and the resulting calibration factors are shown to be in good agreement. Finally, the calibration factor is applied to C-2U experimental data where the measured neutron rate is found to exceed the classical expectation.
authors.affiliation: Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Magee
authors.affiliation: Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688, USA.
authors.forename: R
authors.initials: R
authors.lastname: Clary
authors.affiliation: Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688, USA.
authors.forename: S
authors.initials: S
authors.lastname: Korepanov
authors.affiliation: Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688, USA.
authors.forename: F
authors.initials: F
authors.lastname: Jauregui
authors.affiliation: Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688, USA.
authors.forename: I
authors.initials: I
authors.lastname: Allfrey
authors.affiliation: Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688, USA.
authors.forename: E
authors.initials: E
authors.lastname: Garate
authors.affiliation: Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688, USA.
authors.forename: T
authors.initials: T
authors.lastname: Valentine
authors.affiliation: Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688, USA.
authors.forename: A
authors.initials: A
authors.lastname: Smirnov