Fundamentals of Materials, Techniques, and Instrumentation for OSL and FNTD Dosimetry

Abstract

The optically stimulated luminescence (OSL) technique has already become a successful commercial tool in personal radiation dosimetry, medical dosimetry, diagnostic imaging, geological and archeological dating. This review briefly describes the history and fundamental principles of OSL materials, methods and instrumentation. The advantages of OSL technology and instrumentation in comparison with thermoluminescent technique are analyzed. Progress in material and detector engineering has allowed new and promising developments regarding OSL applications in the medical field. Special attention is dedicated to Al 2 O 3 :C as a material of choice for many dosimetric applications. Different aspects of OSL theory, materials optical and dosimetric properties, instrumentation, and data processing algorithms are described. The next technological breakthrough was done with Fluorescent Nuclear Track Detectors (FNTD) that have some important advantages in measuring fast neutron and high energy heavy charge particles that have become the latest tool in radiation therapy. New Mg-doped aluminum oxide crystals and novel type of imaging instrumentation for FNTD technology are discussed with regard to application in mixed neutron-gamma fields, medical dosimetry and radiobiological research.

An interlaboratory comparison of dosimetry for a multi-institutional radiobiological research project: Observations, problems, solutions and lessons learned

“…Exposure errors recorded with OSL dosimeters implanted into mouse carcasses were uniformly on the high side, suggesting perhaps that they were over responding to relatively low energy x-rays, a phenomenon that has been well-documented with maximum photon energies falling below ~125 KeV (MS Akselrod, personal communication): e.g., at ~100 KeV of photon energy OSL dosimeter signals can be ~1.5 times higher than those OSL signals recorded at substantially higher photon energies, i.e., 150 KeV or greater (Akselrod 2011). Although the dosimetry service provider, Landauer Inc., had attempted to correct for the use of relatively low energy X-rays (OSL signal correction was for 125 KeV) based on the information (or lack thereof) they received back from participating laboratories, these corrections appeared to be insufficient.…”

“…( http://www.landauer.com/uploadedFiles/InLight_nanoDot_FN.pdf). Further details concerning the nature, analytics and calibrations of these OSL dosimeters can be obtained by the reference articles by Akselrod (Akselrod 2011) and Yukihara and McKeever (Yukihara and McKeever 2008, 2011). …”

To Luminesce or to Change Valence? Insight into the Wavelength Dependency of the Reversible Valence Switching of Europium in Sr3SiO5

“…58 Similar phenomena are more common in OSL materials, and high-temperature annealing may be required to address this issue. 59 For example, in the OSL dosimeter phosphor MgB 4 O 7 :Ce 3+ ,Li + , optical bleaching is not able to empty all trapping centers, which can affect the OSL sensitivity. 60,61 Consequently, residual signals due to incompletely bleached trapping centers appear in the following measurement.…”

TL Properties of Pure Al₂O₃ Grown by the Micro-Pulling down Method

“…However, other groups proposed that the 330-nm emission band is originated from a self-trapped exciton (STE) or interstitial Al + I ion [15]. F and F + -centers in Al 2 O 3 :C are known to play a key role in TL and OSL measurement [16,17].…”

“…These Al 2 O 3 crystals were prepared by sintering for ceramics or grown by Al 2 O 3 crystals can be produced by different crystal growth techniques, the most common methods are Czochralski (Cz), Edge-defined Film Growth (EFG or Stepanov), Kiropoulus, Bridgman, Heat Exchange Method (HEM) [17]. We have developed original crystal growth method named a micro-pulling down (µ-PD) method [18,19], and the crystal growth is quickly by 1-2 orders of magnitude than the above methods such as the Cz method.…”