Photoneutron spectrum measured with a Bonner sphere spectrometer in planetary method mode

• The photoneutrons spectrum of a 15 MV LINAC was measured.
• A Bonner sphere spectrometer with pairs of TLDs were used.
• Measurements were carried out with the BSS in Planetary method mode.
• Measured spectrum is compared with calculated spectrum.

The spectrum of photoneutrons produced by a 15 MV VARIAN iX linac working in Bremsstrahlung mode was measured a 100 cm from the IC located 5 cm-depth of a solid water phantom. The spectrum was measured with a Bonner spheres spectrometer with pairs of TLDs as thermal neutron detector. The measurements were carried out using the spectrometer in planetary method mode where a single shoot of the LINAC was required.