Monte Carlo simulation of energy absorbed in phenolic ESR dosimeters added with gadolinium exposed to thermal, epithermal and fast neutrons

Longo, A.; Collura, Giorgio; Gallo, Salvatore; Bartolotta, A.; Marrale, Maurizio

doi:10.1016/j.nimb.2017.08.001

Cited by 3 publications

(2 citation statements)

References 86 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Monte Carlo N-Particle-MCNP5 (79) radiation transport code was used to estimate the average amount of energy deposition per unit mass into lithium formate dosemeters enriched with 6 Li or added with gadolinium oxide. The irradiation set-up adopted was analogous to that used in previous works (42,52,54,80) with the axial system symmetry (see for example Figure 1 of the article (54) ). The LFM samples and the dosemeter holder are cylindrical (diameter = 1 cm) and coaxial.…”

Section: Irradiation Set-upmentioning

confidence: 99%

Improvement of neutron sensitivity for lithium formate EPR dosemeters: a Monte Carlo analysis

D’Oca,

Collura,

Gagliardo

et al. 2023

Radiation Protection Dosimetry

View full text Add to dashboard Cite

This work presents the computational analysis of the sensitivity improvements that could be achieved in lithium formate monohydrate (LFM) electron paramagnetic resonance (EPR) dosemeters exposed to neutron beams. Monte Carlo (MC) simulations were performed on LFM pellets exposed to neutron beams with different energy spectra at various depths inside a water phantom. Various computations were carried out by considering different enrichments of 6Li inside the LFM matrix as well as addition of different amounts of gadolinium oxide inside the pellet blend. The energy released per unit mass was calculated with the aim of predicting the increase in dose achievable by the addition of sensitizers inside the pellets. As expected, a larger amount of 6Li induces an increase of energy released because of the charged secondary particles (i.e. 3H ions and α-particles) produced after neutron capture. For small depths in water phantom and low-energy neutron spectra the dose increase due to 6Li enrichment is high (more than three orders of magnitude with respect to the case of with 7Li). In case of epithermal neutron beams the energy released in 6Li-enriched LFM compound is smaller but larger than in the case of fast neutron beams. On the other hand, the computational analysis evidenced that gadolinium is less effective than 6Li in improving neutron sensitivity of the LFM pellets. Discussion based on the features of MC transport code is provided. This result suggests that 6Li enrichment of LFM dosemeters would be more effective for neutron sensitivity improvement and these EPR dosemeters could be tested for dosimetric applications in Neutron Capture Therapy.

show abstract

Section: Irradiation Set-upmentioning

confidence: 99%

Improvement of neutron sensitivity for lithium formate EPR dosemeters: a Monte Carlo analysis

D’Oca,

Collura,

Gagliardo

et al. 2023

Radiation Protection Dosimetry

View full text Add to dashboard Cite

show abstract

“…Dosimetric ma te ri als of differ ent types have been stud ied over the de cades to as sess their dosimetric per for mance for var i ous ra di a tion beams. Among the var i ous dosimetric sys tems, there are di a mond de tec tors [3], ion iza tion cham bers [4][5][6], scin tilla tors [7], semi con duc tor de tec tors [8], ra dio-chro mic film [9], ESR do sim e ters [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24], thermoluminescent do sim e ters (TLD) [25][26][27][28], and scin til la tion do sim e ters [29]. Of ten these dosimetric sys tems are aided by Monte Carlo sim u la tions that also pro vide many de tails on the par ti cle types and en ergy spec tra [17,30,31].…”

Section: Introductionmentioning

confidence: 99%

Preliminary magnetic resonance relaxometric analysis of Fricke gel dosimeters produced with polyvinyl alcohol and glutaraldehyde

Gallo

Collura

Iacoviello³

et al. 2017

NUCL TECH RAD PROT

View full text Add to dashboard Cite

This work de scribes the pre lim i nary anal y sis of Fricke gels do sim e ters char ac ter ized by a new for mu la tion mak ing use of a ma trix of poly vi nyl al co hol cross-linked by add ing glutaraldehyde and an a lyzed by means of nu clear mag netic res o nance relaxometry. In pre vi ous op ti cal stud ies, these gels have shown prom is ing dosimetric fea tures in terms of pho ton sen si tiv ity and low diffu sion of fer ric ions pro duced af ter ir ra di a tion. In this work, we used a por ta ble nu clear mag netic res o nance relaxometer to mea sure the re laxation times (which are im por tant for dosimetric ap pli ca tions) of these gel ma te ri als. For this pur pose, we per formed a study for op ti miz ing the ac qui si tion pa ram e ters with a nu clear magnetic res o nance relaxometer. Gel sam ples were ex posed to clin i cal 6 MV pho tons in the dose range be tween 0 and 20 Gy. Nu clear mag netic res o nance relaxometry mea sure ments were performed and the sen si tiv ity to pho ton beams was mea sured for var i ous val ues of the Fe 2+ ion con cen tra tion. The anal y ses pointed out that the MR sig nal in creases as the Fe 2+ con tent increases and the in crease is about 75 % when the con cen tra tion of Fe 2+ ions is in creased from 0.5 mM to 2.5 mM. Fur ther more, the sen si tiv ity im prove ment achieved with in creas ing the Fe 2+ con cen tra tion is about 60 %. This pa per shows that the por ta ble nu clear mag netic res onance relaxometer used for anal y sis of po rous ma te ri als can be used for char ac ter iza tion of these dosimetric gels and this study can be con sid ered as the first step for the char ac ter iza tion of these do sim e ters which in fu ture could be used for 3-D dose map ping in clin i cal ap pli ca tions.

show abstract

Characterization of phenolic pellets for ESR dosimetry in photon beam radiotherapy

Gallo

Iacoviello²,

Panzeca

et al. 2017

Radiat Environ Biophys

View full text Add to dashboard Cite

» Download abstractWe report a study of the dosimetric features of phenolic compounds for applications in radiation therapy dosimetry of clinical photon beams by using ESR spectroscopy. After the optimization of the ESR readout parameters, basic dosimetric properties (such as intra-batch reproducibility, dose-response, sensitivity, linearity, dose rate dependence, tissueequivalence and signal stability) of laboratory-made phenolic dosimeters in form of pellets were investigated. Furthermore, these dosimeters were tested for measuring the depth dose profile of a 6 MV clinical photon beam. The results reported show that these dosimeters are promising materials for ESR dosimetric applications in radiation therapy.

show abstract

Monte Carlo simulation of energy absorbed in phenolic ESR dosimeters added with gadolinium exposed to thermal, epithermal and fast neutrons

Cited by 3 publications

References 86 publications

Improvement of neutron sensitivity for lithium formate EPR dosemeters: a Monte Carlo analysis

Improvement of neutron sensitivity for lithium formate EPR dosemeters: a Monte Carlo analysis

Preliminary magnetic resonance relaxometric analysis of Fricke gel dosimeters produced with polyvinyl alcohol and glutaraldehyde

Characterization of phenolic pellets for ESR dosimetry in photon beam radiotherapy

Contact Info

Product

Resources

About