Determination of gamma dose component in thermal column of Pavia Triga reactor by using alanine ESR...

Determination of gamma dose component in thermal column of Pavia Triga reactor

by using alanine ESR detectors

Saverio Altieri

Department of Physics University of Pavia , Italy and

National Institute for Nuclear Physics (INFN)

BNCT preclinical studies at Pavia Triga reactor

• research of new boron carrier

• boron carrier up-take measurements in vitro and vivo in animal models

• test of effectiveness and toxicity of BNCT by irradiation of cell cultures, and animal model of rats and mice treated with new boron compounds

Irradiation position Li-6 neutron shields

low gamma dose irradiation position

Characterization of the irradiation position: neutron flux

nuclear reactor broad energy spectrum Energy range Detector Technique

Thermal (< 0.5 eV)

1/v detector Cd + bare foils

Epithermal (0.5 eV – 10 keV)

Resonance detector

Multifoil set-up

Fast (> 10 keV)

Threshold detector

B + covered foil

multifoil activation + unfolding algorithm

Protti et al., Transactions of the American Nuclear Society, San Diego, California, November 11-15, 2012

Characterization of the irradiation position: microdosimetry

gamma

Dose components

neutrons

BNCT

Colautti et al., Applied Radiation and Isotope (2013)

microdosimetric measurements (mini-TEPCLNL)

Characterization of the irradiation position: gamma dose

in collaboration with University and INFN of Palermo

Alanine dosemeters

Irradiation channel

Simulations of photon background and dose components

MCNP

in the alanine detectors

Simulations of photon background and dose components

MCNP

Simulations of photon background and dose components

MCNP

CPE and calibration

Characterization of the irradiation position: CPE

Characterization of the irradiation position: calibration

Radiotherapy unit in Palermo

Characterization of the irradiation position: calibration

at radiotherapy unit in Palermo

Characterization of the irradiation position: gamma dose

Thermal neutron attenuation 10-3

Characterization of the irradiation position: gamma dose

Characterization of the irradiation position: gamma dose

Characterization of the irradiation position: gamma dose

Characterization of the irradiation position: gamma dose

Characterization of the irradiation position: gamma dose

using non shieded data

Characterization of the irradiation position: gamma dose

and putting RE = 0.4 for thermal neutron

POS 1 Sim 34.82 Gy

Exp 36.76 Gy

POS 2 Sim 14.27 Gy

Exp 14.13 Gy

POS 3 Sim 6.89 Gy

Exp 6.29 Gy

Characterization of the irradiation position: conclusions

Using alanine dosimiters we were able to measure gamma dose in a mixed field (thermal neutron + gamma)

The separation of gamma dose from thermal neutron one was possible thanks to the lithium carbonate shield

We evaluated the alanine RE value for thermal neutrons

Italian BNCT network

University and INFN of PAVIA University of PALERMO University of TORINO University of Piemonte Orientale University of FIRENZE Universitiy of POTENZA Oncological Institute of Veneto (IOV) LNL-INFN

International collaborations

CNEA, Argentina: very active researchers exchange for computational dosimetry, treatment planning, beam design, B concentration measurement methods inter-comparison INL, Idaho, USA: neutron spectrometry in irradiation facilities

http://www.bnct.it

Thank you for your attention

Simulations of photon background and dose components

MCNP