The dose–response of Harshaw TLD-700H

Abstract

Harshaw TLD-700H (7LiF:Mg,Cu,P) was previously characterised for low- to high-dose ranges from 1 microGy to 20 Gy. This paper describes the studies and results of dose-response and linearity at much higher doses. TLD-700H is a near perfect dosimetric material with near tissue equivalence, flat energy response, and the ability to measure beta, gamma and X rays. These new results extend the applicability of Harshaw TLD-700H into more dosimetric measurement environments. The simple glow curve structure provides insignificant fade, eliminating special oven preparation methods experienced by other materials. The work presented in this paper quantifies the performance of Harshaw TLD-700H in extended ranges.

Alpha particle and proton relative thermoluminescence efficiencies in LiF:Mg,Cu,P:is track structure theory up to the task?

“…Low-dose measurements of f (D) following low-LET irradiation indicate decreased TL efficiency for peak 4 beginning at 1 Gy with reported values of f(D)¼0.91+0.01 (1 SD) (49) at 5 Gy in MCP-N and f (D)¼0.96 for TLD-700H (manufactured by Thermo Electron Corporation) at 10 Gy (50) . These slight differences are to be expected in various forms of the material and different methods of analysis (51) .…”

A comprehensive dosimetric evaluation of using RapidArc volumetric‐modulated arc therapy for the treatment of early‐stage nasopharyngeal carcinoma

“…TLD 700H (LiF:Mg,Cu,P) pellets measuring 3.6 mm diameter by 0.38 mm thick were chosen for this experiment. They are of high sensitivity, minimal photon energy dependence and exhibit a lack of supralinearity which enables accurate measurements in low‐dose regions (17) . The Harshaw Model 5500 TLD reader (Thermo Fisher Scientific Inc., Waltham, MA) was used to provide a precise control of the heating regime.…”

The High Dose Response and Functional Capability of the DT-702/Pd Lithium fluoride Thermoluminescent Dosimeter

“…This 30-40% under-response is significantly higher than the 25% under-response for 75 Gy dose previously reported by Velbeck et al (2006) for bare LiF: Mg,Cu,P chips read on a manual planchet reader (Harshaw 3500), which challenges the finding that LiF: Mg,Cu,P would be "very suitable for high-dose measurements." First, when the DT-702/PD is irradiated to 100 Gy from electron or x-ray beams, it under-responds between 30-40% of the delivered dose using the current NDC algorithm.…”

“…The system uses four LiF: Mg, Cu,P-doped thermoluminescent elements that have varying thicknesses and compositions. It has been shown (Velbeck et al 2006) that LiF-700H ( 7 LiF:Mg,Cu,P) material in the form of a bare-pressed pellet of 3.6-mm diameter and 0.38-mm thickness has a useable linear dose range up to 20 Gy. The filters are placed within the 8840 holder such that each element is paired with a different filter.…”

“…As shown in Table 1, four filters are encapsulated within two 0.0048 cm Teflon® sheets (DuPont, Inc., Wilmington, DE, USA), which are mounted on an aluminum substrate (Delzer et al 2008). The Harshaw Model 3500 TLD reader used by Velbeck et al (2006) was a manual planchet reader with ohmic heating technique. The filters, being constructed of different materials, provide each element with a unique absorption thickness in order to allow an estimation of both deep and shallow dose exposures (Cassata et al 2002).…”