Characterization of an extrapolation chamber for low-energy X-rays: Experimental and Monte Carlo preliminary results

The extrapolation chamber is a parallel-plate ionization chamber that allows variation of its air-cavity volume. In this work, an experimental study and MCNP-4C Monte Carlo code simulations of an ionization chamber designed and constructed at the Calibration Laboratory at IPEN to be used as a secondary dosimetry standard for low-energy X-rays are reported. The results obtained were within the international recommendations, and the simulations showed that the components of the extrapolation chamber may influence its response up to 11.0%.

► A homemade extrapolation chamber was studied experimentally and with Monte Carlo. ► It was characterized as a secondary dosimetry standard, for low energy X-rays. ► Several characterization tests were performed and the results were satisfactory. ► Simulation showed that its components may influence the response up to 11.0%. ► This chamber may be used as a secondary standard at our laboratory.