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C Q Tran - One of the best experts on this subject based on the ideXlab platform.
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high accuracy measurement of mass attenuation coefficients and the Imaginary Component of the atomic form factor of zinc from 8 51 kev to 11 59 kev and x ray absorption fine structure with investigation of zinc theory and nanostructure
Journal of Synchrotron Radiation, 2021Co-Authors: Ruwini S K Ekanayake, C T Chantler, Martin D De Jonge, Daniel Sier, Martin J Schalken, Alexis J Illig, Bernt Johannessen, Peter Kappen, C Q TranAbstract:High-accuracy X-ray mass attenuation coefficients were measured from the first X-ray Extended Range Technique (XERT)-like experiment at the Australian Synchrotron. Experimentally measured mass attenuation coefficients deviate by ∼50% from the theoretical values near the zinc absorption edge, suggesting that improvements in theoretical tabulations of mass attenuation coefficients are required to bring them into better agreement with experiment. Using these values the Imaginary Component of the atomic form factor of zinc was determined for all the measured photon energies. The zinc K-edge jump ratio and jump factor are determined and results raise significant questions regarding the definitions of quantities used and best practice for background subtraction prior to X-ray absorption fine-structure (XAFS) analysis. The XAFS analysis shows excellent agreement between the measured and tabulated values and yields bond lengths and nanostructure of zinc with uncertainties of from 0.1% to 0.3% or 0.003 A to 0.008 A. Significant variation from the reported crystal structure was observed, suggesting local dynamic motion of the standard crystal lattice. XAFS is sensitive to dynamic correlated motion and in principle is capable of observing local dynamic motion beyond the reach of conventional crystallography. These results for the zinc absorption coefficient, XAFS and structure are the most accurate structural refinements of zinc at room temperature.
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structure determination from xafs using high accuracy measurements of x ray mass attenuation coefficients of silver 11 kev 28 kev and development of an all energies approach to local dynamical analysis of bond length revealing variation of effective
Journal of Physics: Condensed Matter, 2015Co-Authors: Lachlan J Tantau, C T Chantler, Nicholas A Rae, J D Bourke, M T Islam, A T Payne, C Q TranAbstract:We use the x-ray extended range technique (XERT) to experimentally determine the mass attenuation coefficient of silver in the x-ray energy range 11 kev–28 kev including the silver K absorption edge. The results are accurate to better than 0.1%, permitting critical tests of atomic and solid state theory. This is one of the most accurate demonstrations of cross-platform accuracy in synchrotron studies thus far. We derive the mass absorption coefficients and the Imaginary Component of the form factor over this range. We apply conventional XAFS analytic techniques, extended to include error propagation and uncertainty, yielding bond lengths accurate to approximately 0.24% and thermal Debye–Waller parameters accurate to 30%. We then introduce the FDMX technique for accurate analysis of such data across the full XAFS spectrum, built on full-potential theory, yielding a bond length accuracy of order 0.1% and the demonstration that a single Debye parameter is inadequate and inconsistent across the XAFS range. Two effective Debye–Waller parameters are determined: a high-energy value based on the highly-correlated motion of bonded atoms ( A), and an uncorrelated bulk value ( A) in good agreement with that derived from (room-temperature) crystallography.
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measurements of the x ray mass attenuation coefficient and Imaginary Component of the form factor of copper
Physical Review A, 2008Co-Authors: Jack L Glover, C T Chantler, Z Barnea, Nicholas A Rae, C Q Tran, D C Creagh, David L Paterson, B B DhalAbstract:The x-ray mass-attenuation coefficient of copper was measured at 108 energies between 5 and $20\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ using synchrotron radiation. The measurements are accurate to between 0.09 and 4.5 %, with most measurements being accurate to better than 0.12%. The Imaginary Component of the form factor of copper was also determined after subtracting the attenuation contribution due to scattering. Measurements were made over an extended range of experimental parameter space, allowing us to correct for several systematic errors present in the data. These results represent the most extensive and accurate dataset of their type for copper in the literature and include the important and widely studied region of the $K$-edge and x-ray absorption fine structure. The results are compared with current theoretical tabulations as well as previous experimental measurements and expose inadequacies in both.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of tin over the energy range of 29 60 kev
Physical Review A, 2007Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, David L Paterson, B B Dhal, E P Kanter, S H Southworth, L Young, Mark A BenoAbstract:We use the x-ray extended-range technique (XERT) [C. T. Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60 keV to 0.04-3 % accuracy, and typically in the range 0.1-0.2 %. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct a number of potential experimental systematic errors. These results represent the most extensive experimental data set for tin and include absolute mass attenuation coefficients in the regions of x-ray absorption fine structure, extended x-ray absorption fine structure, and x-ray absorption near-edge structure. The Imaginary Component of the atomic form factor f{sub 2} is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-2 % persist between calculated and observed values.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of molybdenum over the 13 5 41 5 kev energy range
Physical Review A, 2005Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, B B Dhal, David Cookson, Wahkeat Lee, Ali MashayekhiAbstract:We use the x-ray extended-range technique (XERT) [Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of molybdenum in the x-ray energy range of $13.5--41.5\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ to 0.02--0.15 % accuracy. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct where necessary a number of experimental systematic errors. These results represent the most extensive experimental data set for molybdenum and include absolute mass attenuation coefficients in the regions of the x-ray absorption fine structure (XAFS) and x-ray-absorption near-edge structure (XANES). The Imaginary Component of the atomic form-factor ${f}_{2}$ is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1--15 % persist between the calculated and observed values.
C T Chantler - One of the best experts on this subject based on the ideXlab platform.
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high accuracy measurement of mass attenuation coefficients and the Imaginary Component of the atomic form factor of zinc from 8 51 kev to 11 59 kev and x ray absorption fine structure with investigation of zinc theory and nanostructure
Journal of Synchrotron Radiation, 2021Co-Authors: Ruwini S K Ekanayake, C T Chantler, Martin D De Jonge, Daniel Sier, Martin J Schalken, Alexis J Illig, Bernt Johannessen, Peter Kappen, C Q TranAbstract:High-accuracy X-ray mass attenuation coefficients were measured from the first X-ray Extended Range Technique (XERT)-like experiment at the Australian Synchrotron. Experimentally measured mass attenuation coefficients deviate by ∼50% from the theoretical values near the zinc absorption edge, suggesting that improvements in theoretical tabulations of mass attenuation coefficients are required to bring them into better agreement with experiment. Using these values the Imaginary Component of the atomic form factor of zinc was determined for all the measured photon energies. The zinc K-edge jump ratio and jump factor are determined and results raise significant questions regarding the definitions of quantities used and best practice for background subtraction prior to X-ray absorption fine-structure (XAFS) analysis. The XAFS analysis shows excellent agreement between the measured and tabulated values and yields bond lengths and nanostructure of zinc with uncertainties of from 0.1% to 0.3% or 0.003 A to 0.008 A. Significant variation from the reported crystal structure was observed, suggesting local dynamic motion of the standard crystal lattice. XAFS is sensitive to dynamic correlated motion and in principle is capable of observing local dynamic motion beyond the reach of conventional crystallography. These results for the zinc absorption coefficient, XAFS and structure are the most accurate structural refinements of zinc at room temperature.
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structure determination from xafs using high accuracy measurements of x ray mass attenuation coefficients of silver 11 kev 28 kev and development of an all energies approach to local dynamical analysis of bond length revealing variation of effective
Journal of Physics: Condensed Matter, 2015Co-Authors: Lachlan J Tantau, C T Chantler, Nicholas A Rae, J D Bourke, M T Islam, A T Payne, C Q TranAbstract:We use the x-ray extended range technique (XERT) to experimentally determine the mass attenuation coefficient of silver in the x-ray energy range 11 kev–28 kev including the silver K absorption edge. The results are accurate to better than 0.1%, permitting critical tests of atomic and solid state theory. This is one of the most accurate demonstrations of cross-platform accuracy in synchrotron studies thus far. We derive the mass absorption coefficients and the Imaginary Component of the form factor over this range. We apply conventional XAFS analytic techniques, extended to include error propagation and uncertainty, yielding bond lengths accurate to approximately 0.24% and thermal Debye–Waller parameters accurate to 30%. We then introduce the FDMX technique for accurate analysis of such data across the full XAFS spectrum, built on full-potential theory, yielding a bond length accuracy of order 0.1% and the demonstration that a single Debye parameter is inadequate and inconsistent across the XAFS range. Two effective Debye–Waller parameters are determined: a high-energy value based on the highly-correlated motion of bonded atoms ( A), and an uncorrelated bulk value ( A) in good agreement with that derived from (room-temperature) crystallography.
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measurements of the x ray mass attenuation coefficient and Imaginary Component of the form factor of copper
Physical Review A, 2008Co-Authors: Jack L Glover, C T Chantler, Z Barnea, Nicholas A Rae, C Q Tran, D C Creagh, David L Paterson, B B DhalAbstract:The x-ray mass-attenuation coefficient of copper was measured at 108 energies between 5 and $20\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ using synchrotron radiation. The measurements are accurate to between 0.09 and 4.5 %, with most measurements being accurate to better than 0.12%. The Imaginary Component of the form factor of copper was also determined after subtracting the attenuation contribution due to scattering. Measurements were made over an extended range of experimental parameter space, allowing us to correct for several systematic errors present in the data. These results represent the most extensive and accurate dataset of their type for copper in the literature and include the important and widely studied region of the $K$-edge and x-ray absorption fine structure. The results are compared with current theoretical tabulations as well as previous experimental measurements and expose inadequacies in both.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of tin over the energy range of 29 60 kev
Physical Review A, 2007Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, David L Paterson, B B Dhal, E P Kanter, S H Southworth, L Young, Mark A BenoAbstract:We use the x-ray extended-range technique (XERT) [C. T. Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60 keV to 0.04-3 % accuracy, and typically in the range 0.1-0.2 %. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct a number of potential experimental systematic errors. These results represent the most extensive experimental data set for tin and include absolute mass attenuation coefficients in the regions of x-ray absorption fine structure, extended x-ray absorption fine structure, and x-ray absorption near-edge structure. The Imaginary Component of the atomic form factor f{sub 2} is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-2 % persist between calculated and observed values.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of molybdenum over the 13 5 41 5 kev energy range
Physical Review A, 2005Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, B B Dhal, David Cookson, Wahkeat Lee, Ali MashayekhiAbstract:We use the x-ray extended-range technique (XERT) [Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of molybdenum in the x-ray energy range of $13.5--41.5\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ to 0.02--0.15 % accuracy. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct where necessary a number of experimental systematic errors. These results represent the most extensive experimental data set for molybdenum and include absolute mass attenuation coefficients in the regions of the x-ray absorption fine structure (XAFS) and x-ray-absorption near-edge structure (XANES). The Imaginary Component of the atomic form-factor ${f}_{2}$ is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1--15 % persist between the calculated and observed values.
Z Barnea - One of the best experts on this subject based on the ideXlab platform.
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measurements of the x ray mass attenuation coefficient and Imaginary Component of the form factor of copper
Physical Review A, 2008Co-Authors: Jack L Glover, C T Chantler, Z Barnea, Nicholas A Rae, C Q Tran, D C Creagh, David L Paterson, B B DhalAbstract:The x-ray mass-attenuation coefficient of copper was measured at 108 energies between 5 and $20\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ using synchrotron radiation. The measurements are accurate to between 0.09 and 4.5 %, with most measurements being accurate to better than 0.12%. The Imaginary Component of the form factor of copper was also determined after subtracting the attenuation contribution due to scattering. Measurements were made over an extended range of experimental parameter space, allowing us to correct for several systematic errors present in the data. These results represent the most extensive and accurate dataset of their type for copper in the literature and include the important and widely studied region of the $K$-edge and x-ray absorption fine structure. The results are compared with current theoretical tabulations as well as previous experimental measurements and expose inadequacies in both.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of tin over the energy range of 29 60 kev
Physical Review A, 2007Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, David L Paterson, B B Dhal, E P Kanter, S H Southworth, L Young, Mark A BenoAbstract:We use the x-ray extended-range technique (XERT) [C. T. Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60 keV to 0.04-3 % accuracy, and typically in the range 0.1-0.2 %. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct a number of potential experimental systematic errors. These results represent the most extensive experimental data set for tin and include absolute mass attenuation coefficients in the regions of x-ray absorption fine structure, extended x-ray absorption fine structure, and x-ray absorption near-edge structure. The Imaginary Component of the atomic form factor f{sub 2} is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-2 % persist between calculated and observed values.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of molybdenum over the 13 5 41 5 kev energy range
Physical Review A, 2005Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, B B Dhal, David Cookson, Wahkeat Lee, Ali MashayekhiAbstract:We use the x-ray extended-range technique (XERT) [Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of molybdenum in the x-ray energy range of $13.5--41.5\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ to 0.02--0.15 % accuracy. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct where necessary a number of experimental systematic errors. These results represent the most extensive experimental data set for molybdenum and include absolute mass attenuation coefficients in the regions of the x-ray absorption fine structure (XAFS) and x-ray-absorption near-edge structure (XANES). The Imaginary Component of the atomic form-factor ${f}_{2}$ is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1--15 % persist between the calculated and observed values.
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measurement of the x ray mass attenuation coefficient of copper using 8 85 20 kev synchrotron radiation
Physical Review A, 2001Co-Authors: C T Chantler, Z Barnea, C Q Tran, David Cookson, D Paterson, D X BalaicAbstract:This work presents the x-ray extended range technique for measuring x-ray mass attenuation coefficients. This technique includes the use of multiple foil attenuators at each energy investigated, allowing independent tests of detector linearity and of the harmonic contributions to the monochromated synchrotron beam. Measurements over a wide energy range allow the uncertainty of local foil thickness to be minimized by the calibration of thin sample measurements to those of thick samples. The use of an extended criterion for sample thickness selection allows direct determination of dominant systematics, with an improvement of accuracies compared to previous measurements by up to factors of 20. Resulting accuracies for attenuation coefficients of copper ~8.84 to 20 keV! are 0.27‐0.5 %, with reproducibility of 0.02%. We also extract the Imaginary Component of the form factor from the data with the same accuracy. Results are compared to theoretical calculations near and away from the absorption edge. The accuracy challenges available theoretical calculations, and observed discrepancies of 10% between current theory and experiments can now be addressed.
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x ray extended range technique for precision measurement of the x ray mass attenuation coefficient and im f for copper using synchrotron radiation
Physics Letters A, 2001Co-Authors: C T Chantler, C Q Tran, David Cookson, D Paterson, Z BarneaAbstract:We reconsider the long-standing problem of accurate measurement of atomic form factors for fundamental and applied problems. We discuss the X-ray extended-range technique for accurate measurement of the mass attenuation coefficient and the Imaginary Component of the atomic form factor. Novelties of this approach include the use of a synchrotron with detector normalisation, the direct calibration of dominant systematics using multiple thicknesses, and measurement over wide energy ranges with a resulting improvement of accuracies by an order of magnitude. This new technique achieves accuracies of 0.27– 0.5% and reproducibility of 0.02% for attenuation of copper from 8.84 to 20 keV, compared to accuracies of 10% using atomic vapours. This precision challenges available theoretical calculations. Discrepancies of 10% between current theory and experiments can now be addressed. 2001 Elsevier Science B.V. All rights reserved.
B B Dhal - One of the best experts on this subject based on the ideXlab platform.
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measurements of the x ray mass attenuation coefficient and Imaginary Component of the form factor of copper
Physical Review A, 2008Co-Authors: Jack L Glover, C T Chantler, Z Barnea, Nicholas A Rae, C Q Tran, D C Creagh, David L Paterson, B B DhalAbstract:The x-ray mass-attenuation coefficient of copper was measured at 108 energies between 5 and $20\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ using synchrotron radiation. The measurements are accurate to between 0.09 and 4.5 %, with most measurements being accurate to better than 0.12%. The Imaginary Component of the form factor of copper was also determined after subtracting the attenuation contribution due to scattering. Measurements were made over an extended range of experimental parameter space, allowing us to correct for several systematic errors present in the data. These results represent the most extensive and accurate dataset of their type for copper in the literature and include the important and widely studied region of the $K$-edge and x-ray absorption fine structure. The results are compared with current theoretical tabulations as well as previous experimental measurements and expose inadequacies in both.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of tin over the energy range of 29 60 kev
Physical Review A, 2007Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, David L Paterson, B B Dhal, E P Kanter, S H Southworth, L Young, Mark A BenoAbstract:We use the x-ray extended-range technique (XERT) [C. T. Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60 keV to 0.04-3 % accuracy, and typically in the range 0.1-0.2 %. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct a number of potential experimental systematic errors. These results represent the most extensive experimental data set for tin and include absolute mass attenuation coefficients in the regions of x-ray absorption fine structure, extended x-ray absorption fine structure, and x-ray absorption near-edge structure. The Imaginary Component of the atomic form factor f{sub 2} is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-2 % persist between calculated and observed values.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of molybdenum over the 13 5 41 5 kev energy range
Physical Review A, 2005Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, B B Dhal, David Cookson, Wahkeat Lee, Ali MashayekhiAbstract:We use the x-ray extended-range technique (XERT) [Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of molybdenum in the x-ray energy range of $13.5--41.5\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ to 0.02--0.15 % accuracy. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct where necessary a number of experimental systematic errors. These results represent the most extensive experimental data set for molybdenum and include absolute mass attenuation coefficients in the regions of the x-ray absorption fine structure (XAFS) and x-ray-absorption near-edge structure (XANES). The Imaginary Component of the atomic form-factor ${f}_{2}$ is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1--15 % persist between the calculated and observed values.
Martin D De Jonge - One of the best experts on this subject based on the ideXlab platform.
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high accuracy measurement of mass attenuation coefficients and the Imaginary Component of the atomic form factor of zinc from 8 51 kev to 11 59 kev and x ray absorption fine structure with investigation of zinc theory and nanostructure
Journal of Synchrotron Radiation, 2021Co-Authors: Ruwini S K Ekanayake, C T Chantler, Martin D De Jonge, Daniel Sier, Martin J Schalken, Alexis J Illig, Bernt Johannessen, Peter Kappen, C Q TranAbstract:High-accuracy X-ray mass attenuation coefficients were measured from the first X-ray Extended Range Technique (XERT)-like experiment at the Australian Synchrotron. Experimentally measured mass attenuation coefficients deviate by ∼50% from the theoretical values near the zinc absorption edge, suggesting that improvements in theoretical tabulations of mass attenuation coefficients are required to bring them into better agreement with experiment. Using these values the Imaginary Component of the atomic form factor of zinc was determined for all the measured photon energies. The zinc K-edge jump ratio and jump factor are determined and results raise significant questions regarding the definitions of quantities used and best practice for background subtraction prior to X-ray absorption fine-structure (XAFS) analysis. The XAFS analysis shows excellent agreement between the measured and tabulated values and yields bond lengths and nanostructure of zinc with uncertainties of from 0.1% to 0.3% or 0.003 A to 0.008 A. Significant variation from the reported crystal structure was observed, suggesting local dynamic motion of the standard crystal lattice. XAFS is sensitive to dynamic correlated motion and in principle is capable of observing local dynamic motion beyond the reach of conventional crystallography. These results for the zinc absorption coefficient, XAFS and structure are the most accurate structural refinements of zinc at room temperature.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of tin over the energy range of 29 60 kev
Physical Review A, 2007Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, David L Paterson, B B Dhal, E P Kanter, S H Southworth, L Young, Mark A BenoAbstract:We use the x-ray extended-range technique (XERT) [C. T. Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60 keV to 0.04-3 % accuracy, and typically in the range 0.1-0.2 %. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct a number of potential experimental systematic errors. These results represent the most extensive experimental data set for tin and include absolute mass attenuation coefficients in the regions of x-ray absorption fine structure, extended x-ray absorption fine structure, and x-ray absorption near-edge structure. The Imaginary Component of the atomic form factor f{sub 2} is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-2 % persist between calculated and observed values.
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measurement of the x ray mass attenuation coefficient and determination of the Imaginary Component of the atomic form factor of molybdenum over the 13 5 41 5 kev energy range
Physical Review A, 2005Co-Authors: Martin D De Jonge, C T Chantler, Z Barnea, C Q Tran, B B Dhal, David Cookson, Wahkeat Lee, Ali MashayekhiAbstract:We use the x-ray extended-range technique (XERT) [Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of molybdenum in the x-ray energy range of $13.5--41.5\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ to 0.02--0.15 % accuracy. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct where necessary a number of experimental systematic errors. These results represent the most extensive experimental data set for molybdenum and include absolute mass attenuation coefficients in the regions of the x-ray absorption fine structure (XAFS) and x-ray-absorption near-edge structure (XANES). The Imaginary Component of the atomic form-factor ${f}_{2}$ is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1--15 % persist between the calculated and observed values.