Energy response of glass bead TLDs irradiated with radiation therapy beams

Feasibility study of silica bead thermoluminescence detectors (TLDs) in an external radiotherapy dosimetry audit programme

“…However, all the values are within measurement uncertainty and so it is not possible to form a firm conclusion. The density of silica beads is less than that of diodes [15], which are routine dosimeters for clinical dosimetry [29], hence if there is over response it is expected to be much less than that of the diodes which is reported by Huang et al [30].…”

“…Linearity of dose response covering the range of radiotherapy dose levels (1cGy to 50Gy), had a correlation coefficient of R 2 ≥ 0.999; therefore, the large dose differences between reference dose measurement and the audit dose levels can be considered to have a negligible calibration error. Energy response was fairly uniform across the MV photon beams and the maximum percentage difference compared to that obtained at 6 MV photons being -3.8% for 15 MV photons [15]. The energy response is considered of relevance for the use of dosimeters in postal audit situations where each institution may have slightly different quality index (QI) for their respective photon energies thus ensuring that the calibration may still be considered valid when same nominal beam energy is used.…”

“…A batch of transparent silica beads, 2 mm diameter and 1 mm thick outer shell (Petite: Stock#: G42010, Mill Hill, Japan) with material composition (by weight): C-8.93%, O-42.18%, Na-10.55%, Al-1.3%, Si-33.62%, K-1.09%, Ca-1.92%, Fe-0.37% [15] was selected for this work. The silica beads were initially produced as jewellery silica beads and preparation was required for them to be used as TLDs.…”

“…Silica beads have previously been characterised as novel high spatial resolution micro TLDs [14,15,16,17,18]. The particular silica beads employed have several potentially favourable physical characteristics as dosimeters in postal dosimetry audit of advanced radiotherapy.…”

ESR dosimeter material properties of phenols compound exposed to radiotherapeutic electron beams

“…Among the various dosimetric systems there are ionization chambers [1], semiconductor detectors [2], radiochromic films [3][4][5][6], thermoluminescence (TLD) and optically stimulated luminescence dosimeters (OSL) [7][8][9][10][11][12][13][14], scintillation dosimeters [15][16][17][18] and gel dosimetry [19][20][21][22][23][24][25][26], all of which have advantages and disadvantages [27].…”