access icon openaccess Monte–Carlo simulation of wall correction factor of graphite cavity ionisation chamber

The purpose of this article is to discuss the method of determining the wall correction factor of graphite cavity ionisation chamber. The method is the ‘equal effect wall thickness’ simulation and direct calculation of the wall correction factor of the std10cm3 and std30cm3 spherical graphite cavity ionisation chamber in the national air-specific kinetic energy reference group (National Institute of Standards and Technology NIST), respectively, in the NIST10cm3 and NIST30cm3 spherical graphite cavity ionisation chamber. The calculated results are in agreement with the values released by NIST in 0.1%. Conclusions of the equivalent wall thickness simulation method and the direct calculation simulation method meet each other's requirements, which provide a new idea for the determination of wall correction factor.

Inspec keywords: Monte Carlo methods; graphite; ionisation chambers

Other keywords: graphite cavity ionisation chamber; equivalent wall thickness simulation method; National Institute of Standards and Technology; wall correction factor; equal effect wall thickness; national air-specific kinetic energy reference group; spherical graphite cavity; direct calculation simulation method; NIST; monte–Carlo simulation

Subjects: Ionisation chambers; Particle and radiation detection and measurement

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