H R Verma - Academia.edu (original) (raw)
Papers by H R Verma
X-ray Fluorescence (XRF) and Particle-Induced X-ray Emission (PIXE).- Rutherford Backscattering S... more X-ray Fluorescence (XRF) and Particle-Induced X-ray Emission (PIXE).- Rutherford Backscattering Spectroscopy.- Elastic Recoil Detection.- Mossbauer Spectroscopy (MS).- X-Ray Photoelectron Spectroscopy.- Neutron Activation Analysis.- Nuclear Reaction Analysis and Particle-Induced Gamma-Ray Emission.- Accelerator Mass Spectrometry (AMS).
Indian Journal of Pure & Applied Physics, 1993
Results from measurements of K-shell ionization cross sections of the elements Cr, Ni and Cu by e... more Results from measurements of K-shell ionization cross sections of the elements Cr, Ni and Cu by electron impact with energies in the range 6.5-40 keV are presented. Cross sections were obtained by measuring characteristic x-rays emitted from (1-6 nm thick) films of the studied elements deposited on self-supporting carbon backing films. The procedure yields relative cross sections with uncertainties of the order of 2%. Transformation to absolute units increases the uncertainties to about 10%. Our results are compared with those from other groups and with two calculations based on the first Born approximation, which include corrections for exchange, Coulomb and relativistic effects. A simple empirical formula that accurately describes the energy dependence of the measured cross sections is provided.
Applied Radiation and Isotopes, 2017
Tienda online donde Comprar Atomic and Nuclear Analytical Methods · XRF, MA¶ssbauer, XPS, NAA and... more Tienda online donde Comprar Atomic and Nuclear Analytical Methods · XRF, MA¶ssbauer, XPS, NAA and Ion-Beam Spectroscopic Techniques al precio 166,49 € de Verma, H.R., tienda de Libros de Medicina, Libros de Quimica - Quimica
Journal of Physics B: Atomic and Molecular Physics
... Instrum. Meth. 178 481 Garg ML, Singh J, Verma HR, Singh N, Mangal PC and Trehan PN 1984 J. P... more ... Instrum. Meth. 178 481 Garg ML, Singh J, Verma HR, Singh N, Mangal PC and Trehan PN 1984 J. Phys. B: At. Mol. Phys. 17 Garg ML, Mehta D, Kumar S, Mangal PC and Trehan PN 1985 J. X-ray Spectrom. to be published Khan Md R and Karimi M 1980 X-ray Spectrom. ...
Journal of Physics C: Solid State Physics
Structural and magnetic changes with composition in the (Fe1-xMnx)2P system with 0.01<or=x<... more Structural and magnetic changes with composition in the (Fe1-xMnx)2P system with 0.01<or=x<or=0.85 have been investigated by means of X-ray diffraction and 57Fe Mossbauer spectroscopic techniques. (Fe1-xMnx)2P crystallises with the hexagonal Fe2P-type structure for x0.70 and with the orthorhombic Co2P-type structure for 0.26<x<0.68. Manganese substitutes preferentially for iron at the Fe(2) position in both the Fe2P and Co2P structures. Magnetic hyperfine fields, centroid shifts and quadrupole splittings are reported, as well as the results of magnetisation measurements for (Fe0.97Mn0.03)2P at 4.2K in fields up to 12 T.
Journal of Physics B: Atomic and Molecular Physics
... There are Page 5. 1136 HR Verma, D Pal, M L Garg and PN Trehan certain weak x-ray lines which... more ... There are Page 5. 1136 HR Verma, D Pal, M L Garg and PN Trehan certain weak x-ray lines which cannot be resolved due to a very small energy difference from the intense lines and hence overlap in the intense peaks. For ...
Radiation Physics and Chemistry, 1998
Journal of Physics B: Atomic and Molecular Physics, 1987
... ratios for Gd and Tb in the energy range 250-400 keV Harsh Mohan, Panjit S Singh, D Singh, HR... more ... ratios for Gd and Tb in the energy range 250-400 keV Harsh Mohan, Panjit S Singh, D Singh, HR Verma and C S Khurana Department of Physics, Punjabi University, Patiala-147 002, India Received 13 April 1987, in final form 3 July 1987 Abstract. ...
Journal of Physics B: Atomic and Molecular Physics, 1984
... Au, Pb and Bi in the energy range 17-60 keV M L Garg, Jasbir Singh, H R Vermat, Nirmal Singh,... more ... Au, Pb and Bi in the energy range 17-60 keV M L Garg, Jasbir Singh, H R Vermat, Nirmal Singh, PC MangalS and PN Trehan Department of Physics, Panjab University, Chandigarh-160014, India Received 20 September 1983 Abstract. ...
Physica B+C, 1987
The L-shell X-ray production cross-sections, viz. σ Lα , σ Lβ and σ Lγ of Yb have been measured b... more The L-shell X-ray production cross-sections, viz. σ Lα , σ Lβ and σ Lγ of Yb have been measured by means of proton-induced ionization in the energy region of 250400 keV. The thick target X-ray yields have been measured using a HPGe detector. The theoretical calculations for ...
X-Ray Spectrometry, 1985
The K and L x-ray emission intensities per 100 disintegrations have been calculated for some radi... more The K and L x-ray emission intensities per 100 disintegrations have been calculated for some radionuclides using the latest adopted data for gamma-ray intensities, electron capture and internal conversion coefficients for the parent nuclides, fluorescence yield values, Coster-Kronig transition probabilities, average total number of primary L shell vacancies produced in the decay of K shell vacancies and emission rates for various shells and subshells for the daughter nuclei. The results are in good agreement with theoretical and experimental values for the K x-ray intensities. There are no experimental mults available to compare with the present calculations for the L x-ray intensities; however, there is a marked discrepancy in the La and Lp intensities available on the basis of theoretical estimates.
X-Ray Spectrometry, 1987
ABSTRACT A radial efficiency correction factor was introduced in the five-parameter radially depe... more ABSTRACT A radial efficiency correction factor was introduced in the five-parameter radially dependent model by Cohen to calculate the theoretical efficiency of an Si(Li) detector. The present calculations for the various detectors confirm that the radial dependent factor introduced by Cohen is a geometry-dependent factor and does not depend on the physical characteristics of the detector. The modified five-parameter model suggested in this study removes the anomaly between the theoretical calculations and experimental observations.
Radiation Physics and Chemistry, 1998
Pramana, 1985
... lnstrum. Methods 193 91 Erdtman G and Soyka W 1974 Die F-Linen der Radionukfide, Band 1-3, Ke... more ... lnstrum. Methods 193 91 Erdtman G and Soyka W 1974 Die F-Linen der Radionukfide, Band 1-3, Kernforschunganalage Julich, Report jil 1003-AC Garg ML, Singh J, Verma HR, Singh N, Mangal PC and Trehan PN 1984a J. Phys. ...
Pramana, 1991
K-shell ionization cross section measurements are reported for35Br,37Rb and39Y targets caused by ... more K-shell ionization cross section measurements are reported for35Br,37Rb and39Y targets caused by protons over 300–400 keV energy range in 20 keV increment. The K-shell ionization cross sections (σ k l ) at different energies were deduced from the Kα and Kβ X-ray production cross sections which were obtained from X-ray yields of the Kα and Kβ transitions. The experimental values are compared with the calculated values of ECPSSR theory and empirical reference cross sections. The resultant K-shell ionization cross sections are found to be in reasonable agreement with the ECPSSR theory. The Kα/Kβ intensity ratios are also presented and compared with other experimental values and also with the theoretical one-hole values given by Scofield.
Journal of Physics C: Solid State Physics, 1987
Structural and magnetic changes with composition in the (Fe1-xMnx)2P system with 0.01<or=x<... more Structural and magnetic changes with composition in the (Fe1-xMnx)2P system with 0.01<or=x<or=0.85 have been investigated by means of X-ray diffraction and 57Fe Mossbauer spectroscopic techniques. (Fe1-xMnx)2P crystallises with the hexagonal Fe2P-type structure for x0.70 and with the orthorhombic Co2P-type structure for 0.26<x<0.68. Manganese substitutes preferentially for iron at the Fe(2) position in both the Fe2P and Co2P structures. Magnetic hyperfine fields, centroid shifts and quadrupole splittings are reported, as well as the results of magnetisation measurements for (Fe0.97Mn0.03)2P at 4.2K in fields up to 12 T.
Physica Scripta, 1985
The amorphous metallic glasses Fe75Al5B20 and Fe75Al10B15 and the phases found after crystallizat... more The amorphous metallic glasses Fe75Al5B20 and Fe75Al10B15 and the phases found after crystallization have been studied by M?ssbauer spectroscopy between 80 K and 1025 K. The Curie temperatures for these two glasses have been found to be 720 ? 5 K and 685 ? 10 K respectively. The onset of crystallization for Fe75Al5B20 and Fe75Al10B15 has been found at 745 K and 700 K respectively under heating rates of 10 K/min, while the Curie temperatures of the crystallized phases are about 1000 K. The amorphous phases of the two samples have a hyperfine field distribution with a relative width of about 15%. The hyperfine parameters are found to be correlated, as is evident from the line width asymmetry observed in all of the measured spectra. The linear correlations are -0.045(5), +0.025(5) and -0.005(2) for the relations between magnetic/electric quadrupole, magnetic/isomer shift and electric quadrupole/isomer shift distributions respectively. The correlation analysis does, however, indicate that the relations are more complex. Thus the linear correlation coefficient for the dominant relation above is only 20% for both compositions studied.
X-ray Fluorescence (XRF) and Particle-Induced X-ray Emission (PIXE).- Rutherford Backscattering S... more X-ray Fluorescence (XRF) and Particle-Induced X-ray Emission (PIXE).- Rutherford Backscattering Spectroscopy.- Elastic Recoil Detection.- Mossbauer Spectroscopy (MS).- X-Ray Photoelectron Spectroscopy.- Neutron Activation Analysis.- Nuclear Reaction Analysis and Particle-Induced Gamma-Ray Emission.- Accelerator Mass Spectrometry (AMS).
Indian Journal of Pure & Applied Physics, 1993
Results from measurements of K-shell ionization cross sections of the elements Cr, Ni and Cu by e... more Results from measurements of K-shell ionization cross sections of the elements Cr, Ni and Cu by electron impact with energies in the range 6.5-40 keV are presented. Cross sections were obtained by measuring characteristic x-rays emitted from (1-6 nm thick) films of the studied elements deposited on self-supporting carbon backing films. The procedure yields relative cross sections with uncertainties of the order of 2%. Transformation to absolute units increases the uncertainties to about 10%. Our results are compared with those from other groups and with two calculations based on the first Born approximation, which include corrections for exchange, Coulomb and relativistic effects. A simple empirical formula that accurately describes the energy dependence of the measured cross sections is provided.
Applied Radiation and Isotopes, 2017
Tienda online donde Comprar Atomic and Nuclear Analytical Methods · XRF, MA¶ssbauer, XPS, NAA and... more Tienda online donde Comprar Atomic and Nuclear Analytical Methods · XRF, MA¶ssbauer, XPS, NAA and Ion-Beam Spectroscopic Techniques al precio 166,49 € de Verma, H.R., tienda de Libros de Medicina, Libros de Quimica - Quimica
Journal of Physics B: Atomic and Molecular Physics
... Instrum. Meth. 178 481 Garg ML, Singh J, Verma HR, Singh N, Mangal PC and Trehan PN 1984 J. P... more ... Instrum. Meth. 178 481 Garg ML, Singh J, Verma HR, Singh N, Mangal PC and Trehan PN 1984 J. Phys. B: At. Mol. Phys. 17 Garg ML, Mehta D, Kumar S, Mangal PC and Trehan PN 1985 J. X-ray Spectrom. to be published Khan Md R and Karimi M 1980 X-ray Spectrom. ...
Journal of Physics C: Solid State Physics
Structural and magnetic changes with composition in the (Fe1-xMnx)2P system with 0.01<or=x<... more Structural and magnetic changes with composition in the (Fe1-xMnx)2P system with 0.01<or=x<or=0.85 have been investigated by means of X-ray diffraction and 57Fe Mossbauer spectroscopic techniques. (Fe1-xMnx)2P crystallises with the hexagonal Fe2P-type structure for x0.70 and with the orthorhombic Co2P-type structure for 0.26<x<0.68. Manganese substitutes preferentially for iron at the Fe(2) position in both the Fe2P and Co2P structures. Magnetic hyperfine fields, centroid shifts and quadrupole splittings are reported, as well as the results of magnetisation measurements for (Fe0.97Mn0.03)2P at 4.2K in fields up to 12 T.
Journal of Physics B: Atomic and Molecular Physics
... There are Page 5. 1136 HR Verma, D Pal, M L Garg and PN Trehan certain weak x-ray lines which... more ... There are Page 5. 1136 HR Verma, D Pal, M L Garg and PN Trehan certain weak x-ray lines which cannot be resolved due to a very small energy difference from the intense lines and hence overlap in the intense peaks. For ...
Radiation Physics and Chemistry, 1998
Journal of Physics B: Atomic and Molecular Physics, 1987
... ratios for Gd and Tb in the energy range 250-400 keV Harsh Mohan, Panjit S Singh, D Singh, HR... more ... ratios for Gd and Tb in the energy range 250-400 keV Harsh Mohan, Panjit S Singh, D Singh, HR Verma and C S Khurana Department of Physics, Punjabi University, Patiala-147 002, India Received 13 April 1987, in final form 3 July 1987 Abstract. ...
Journal of Physics B: Atomic and Molecular Physics, 1984
... Au, Pb and Bi in the energy range 17-60 keV M L Garg, Jasbir Singh, H R Vermat, Nirmal Singh,... more ... Au, Pb and Bi in the energy range 17-60 keV M L Garg, Jasbir Singh, H R Vermat, Nirmal Singh, PC MangalS and PN Trehan Department of Physics, Panjab University, Chandigarh-160014, India Received 20 September 1983 Abstract. ...
Physica B+C, 1987
The L-shell X-ray production cross-sections, viz. σ Lα , σ Lβ and σ Lγ of Yb have been measured b... more The L-shell X-ray production cross-sections, viz. σ Lα , σ Lβ and σ Lγ of Yb have been measured by means of proton-induced ionization in the energy region of 250400 keV. The thick target X-ray yields have been measured using a HPGe detector. The theoretical calculations for ...
X-Ray Spectrometry, 1985
The K and L x-ray emission intensities per 100 disintegrations have been calculated for some radi... more The K and L x-ray emission intensities per 100 disintegrations have been calculated for some radionuclides using the latest adopted data for gamma-ray intensities, electron capture and internal conversion coefficients for the parent nuclides, fluorescence yield values, Coster-Kronig transition probabilities, average total number of primary L shell vacancies produced in the decay of K shell vacancies and emission rates for various shells and subshells for the daughter nuclei. The results are in good agreement with theoretical and experimental values for the K x-ray intensities. There are no experimental mults available to compare with the present calculations for the L x-ray intensities; however, there is a marked discrepancy in the La and Lp intensities available on the basis of theoretical estimates.
X-Ray Spectrometry, 1987
ABSTRACT A radial efficiency correction factor was introduced in the five-parameter radially depe... more ABSTRACT A radial efficiency correction factor was introduced in the five-parameter radially dependent model by Cohen to calculate the theoretical efficiency of an Si(Li) detector. The present calculations for the various detectors confirm that the radial dependent factor introduced by Cohen is a geometry-dependent factor and does not depend on the physical characteristics of the detector. The modified five-parameter model suggested in this study removes the anomaly between the theoretical calculations and experimental observations.
Radiation Physics and Chemistry, 1998
Pramana, 1985
... lnstrum. Methods 193 91 Erdtman G and Soyka W 1974 Die F-Linen der Radionukfide, Band 1-3, Ke... more ... lnstrum. Methods 193 91 Erdtman G and Soyka W 1974 Die F-Linen der Radionukfide, Band 1-3, Kernforschunganalage Julich, Report jil 1003-AC Garg ML, Singh J, Verma HR, Singh N, Mangal PC and Trehan PN 1984a J. Phys. ...
Pramana, 1991
K-shell ionization cross section measurements are reported for35Br,37Rb and39Y targets caused by ... more K-shell ionization cross section measurements are reported for35Br,37Rb and39Y targets caused by protons over 300–400 keV energy range in 20 keV increment. The K-shell ionization cross sections (σ k l ) at different energies were deduced from the Kα and Kβ X-ray production cross sections which were obtained from X-ray yields of the Kα and Kβ transitions. The experimental values are compared with the calculated values of ECPSSR theory and empirical reference cross sections. The resultant K-shell ionization cross sections are found to be in reasonable agreement with the ECPSSR theory. The Kα/Kβ intensity ratios are also presented and compared with other experimental values and also with the theoretical one-hole values given by Scofield.
Journal of Physics C: Solid State Physics, 1987
Structural and magnetic changes with composition in the (Fe1-xMnx)2P system with 0.01<or=x<... more Structural and magnetic changes with composition in the (Fe1-xMnx)2P system with 0.01<or=x<or=0.85 have been investigated by means of X-ray diffraction and 57Fe Mossbauer spectroscopic techniques. (Fe1-xMnx)2P crystallises with the hexagonal Fe2P-type structure for x0.70 and with the orthorhombic Co2P-type structure for 0.26<x<0.68. Manganese substitutes preferentially for iron at the Fe(2) position in both the Fe2P and Co2P structures. Magnetic hyperfine fields, centroid shifts and quadrupole splittings are reported, as well as the results of magnetisation measurements for (Fe0.97Mn0.03)2P at 4.2K in fields up to 12 T.
Physica Scripta, 1985
The amorphous metallic glasses Fe75Al5B20 and Fe75Al10B15 and the phases found after crystallizat... more The amorphous metallic glasses Fe75Al5B20 and Fe75Al10B15 and the phases found after crystallization have been studied by M?ssbauer spectroscopy between 80 K and 1025 K. The Curie temperatures for these two glasses have been found to be 720 ? 5 K and 685 ? 10 K respectively. The onset of crystallization for Fe75Al5B20 and Fe75Al10B15 has been found at 745 K and 700 K respectively under heating rates of 10 K/min, while the Curie temperatures of the crystallized phases are about 1000 K. The amorphous phases of the two samples have a hyperfine field distribution with a relative width of about 15%. The hyperfine parameters are found to be correlated, as is evident from the line width asymmetry observed in all of the measured spectra. The linear correlations are -0.045(5), +0.025(5) and -0.005(2) for the relations between magnetic/electric quadrupole, magnetic/isomer shift and electric quadrupole/isomer shift distributions respectively. The correlation analysis does, however, indicate that the relations are more complex. Thus the linear correlation coefficient for the dominant relation above is only 20% for both compositions studied.