Glow Curve Analysis Applied to the Discrimination of X Ray Versus Proton Irradiation

2002 ◽  
Vol 101 (1) ◽  
pp. 99-102 ◽  
Author(s):  
M. Skopec ◽  
J. L. Price ◽  
N. Guardala ◽  
M. Loew ◽  
M. Moscovitch
Keyword(s):  
Glow Curve ◽  
Proton Irradiation ◽  
Curve Analysis ◽  
X Ray

Glow Curve Analysis: A Method for Improving TLD Reliability

1992 ◽  
Vol 43 (1-4) ◽  
pp. 143-146 ◽  
Author(s):  
A. Delgado ◽  
J.M. Gómez Ros
Keyword(s):  
Glow Curve ◽  
Curve Analysis

The Performance of Channel Cut Collimators for Precision X-Ray Diffraction Studies of Epitaxial Layers

1990 ◽  
Vol 208 ◽  
Author(s):  
Neil Loxley ◽  
D. Keith Bowen ◽  
Brian K. Tanner
Keyword(s):  
Grazing Incidence ◽  
Curve Analysis ◽  
Epitaxial Layers ◽  
Angular Divergence ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
Experimental Performance ◽  
Low Background ◽  
X Ray ◽  
Angle Scattering

ABSTRACTReplacement of the pinhole collimator on a double axis X-ray diffractometer with a device incorporating a channel-cut crystal permits the beam to be pre-conditioned in angular divergence. We examine the merits of such devices, known as channel-cut collimators (CCC's), of different materials and reflections. The experimental performance of InP 004 and Si 022 CCC's is presented.With a reference crystal on the first axis, set in the dispersive peometry with respect to the CCC, conditioning in wavelength spread is achieved. Dispersion broadening is effectively eliminated and no resetting of the reference crystal is required when changing specimen materials or reflections. The devices have extremely low background and reduced Bragg tails. Application of the 4-reflection CCC to rocking curve analysis of thin epitaxial layers, ultra-low angle scattering from biological systems, grazing incidence reflectometry and triple axis diffraction of semi-conductors is discussed.

scholarly journals Влияние толщины пленки Pt на изменение текстуры и доли кристаллической фазы при ее отжиге

2020 ◽  
Vol 90 (5) ◽  
pp. 795
Author(s):  
Р.В. Селюков ◽  
В.В. Наумов
Keyword(s):  
Volume Fraction ◽  
Curve Analysis ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
X Ray ◽  
Texture Parameters ◽  
Sputter Deposited ◽  
Pt Films ◽  
H 20

Textured Pt films with thickness h=20-80 nm were sputter deposited on oxidized c-Si (100) wafers and annealed in vacuum at 500°C/60 min. The thickness dependencies of the crystalline texture parameters and of the fraction of crystalline phase δ are obtained for as-deposited and annealed films using X-ray diffraction. The determination of δ in textured films is carried out by the new method based on rocking curve analysis. It is found that annealing leads to the texture improvement and to the increasing of δ for all h. The less h, the stronger effects of texture improvement and of δ increasing. These results are explained by the annealing-induced formation of large secondary grains whose volume fraction increases as h decreases. The inhomogeneity of the depth distributions of texture parameters and of δ are investigated for the as-deposited Pt films.

An Overview on Peak Shape Method for Thermoluminescence Glow Curve Analysis

2018 ◽  
pp. 26-52
Author(s):  
Sukhamoy Bhattacharyya ◽  
Partha Sarathi Majumdar
Keyword(s):  
Activation Energy ◽  
Glow Curve ◽  
Frequency Factor ◽  
Curve Analysis ◽  
Peak Shape ◽  
Order Of Kinetics ◽  
Symmetry Factor ◽  
Alternative Approach ◽  
General Order ◽  
Thermoluminescence Glow Curve

The shape of a thermoluminescence (TL) glow curve has fundamental importance for calculating the characteristic parameters of trap levels within the band gap. TL analysis are mostly based on the three-parameter general order kinetics model. The parameters are activation energy, order of kinetics, and frequency factor. Peak shape method is one of the most prominent methods for extracting the activation energy from a TL curve. An overview of different peak shape methods along with an alternative approach formulated directly from basic TL equations is presented in this chapter. Generally, peak shape method requires prior knowledge of order of kinetics to determine activation energy which creates a difficulty due to the non-uniqueness of symmetry factor for a particular value of order of kinetics. A modified version of peak shape method which is free from this constraint is discussed here. Activation energies from experimental curves of tremolite and actinolite are estimated using peak shape method. Limitation of peak shape method for saturated TL peaks with heavy retrapping is also discussed.

scholarly journals Thermoluminescence Characteristics of Terbium Doped Zinc Borates

Crystals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 557 ◽  
Author(s):  
Nil Kucuk
Keyword(s):  
Glow Curve ◽  
Single Phase ◽  
Peak Shape ◽  
X Ray Diffraction ◽  
X Ray ◽  
Initial Rise ◽  
Linear Behavior ◽  
Minimum Detectable Dose ◽  
Xrd Studies ◽  
Dose Responses

In this work, structural and thermoluminescence (TL) characteristics for ZnB2O4:xTb3+ (x = 0.01, 0.02, 0.03, 0.04, 0.05, and 0.10 mole) phosphors were investigated. The phosphors were prepared via synthesis of nitric acid. The X-ray diffraction (XRD) studies show that the synthesized samples can be indexed to nearly single-phase cubic ZnB2O4. The TL characteristics following 90Sr beta irradiation (40 mCi) were studied. TL intensity is found to depend on Tb concentration. The optimal concentration of the doped Tb3+ is 0.03 mol in TL measurements. TL dose responses of the phosphors to beta doses of 0.143, 0.715, 1.43, 15, 30 and 60 Gy showed fairly linear behavior. The minimum detectable dose (MDD) value for ZnB2O4:0.04Tb3+ was found to be 87 mGy. The kinetic parameters of the ZnB2O4:0.03Tb3+ sample were estimated by the glow curve deconvolution, the initial rise, the curve fitting, and the peak shape methods. The results indicate that these phosphors are thought to be promising candidates as TL materials. The results provide valuable knowledge of the characteristics of Tb-doped ZnB2O4 for use in dosimetry research.

scholarly journals Proton Irradiation Increases the Necessity for Homologous Recombination Repair Along with the Indispensability of Non-Homologous End Joining

Cells ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 889 ◽  
Author(s):  
Klaudia Szymonowicz ◽  
Adam Krysztofiak ◽  
Jansje van der Linden ◽  
Ajvar Kern ◽  
Simon Deycmar ◽  
...  
Keyword(s):  
Dna Damage ◽  
Homologous Recombination ◽  
Proton Irradiation ◽  
Negative Impact ◽  
Particle Therapy ◽  
Homologous Recombination Repair ◽  
End Joining ◽  
X Ray ◽  
Recombination Repair ◽  
Non Homologous End Joining

Technical improvements in clinical radiotherapy for maximizing cytotoxicity to the tumor while limiting negative impact on co-irradiated healthy tissues include the increasing use of particle therapy (e.g., proton therapy) worldwide. Yet potential differences in the biology of DNA damage induction and repair between irradiation with X-ray photons and protons remain elusive. We compared the differences in DNA double strand break (DSB) repair and survival of cells compromised in non-homologous end joining (NHEJ), homologous recombination repair (HRR) or both, after irradiation with an equal dose of X-ray photons, entrance plateau (EP) protons, and mid spread-out Bragg peak (SOBP) protons. We used super-resolution microscopy to investigate potential differences in spatial distribution of DNA damage foci upon irradiation. While DNA damage foci were equally distributed throughout the nucleus after X-ray photon irradiation, we observed more clustered DNA damage foci upon proton irradiation. Furthermore, deficiency in essential NHEJ proteins delayed DNA repair kinetics and sensitized cells to both, X-ray photon and proton irradiation, whereas deficiency in HRR proteins sensitized cells only to proton irradiation. We assume that NHEJ is indispensable for processing DNA DSB independent of the irradiation source, whereas the importance of HRR rises with increasing energy of applied irradiation.

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