This paper describes the standardization of the proton-induced x-ray emission（PIXE） technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard refe...This paper describes the standardization of the proton-induced x-ray emission（PIXE） technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard reference materials（SRMs） were analyzed using this technique and the data were compared with the already known data of these certified SRMs. These samples were selected in order to cover the maximum range of elements in the periodic table. Each sample was irradiated for three different values of collected beam charges at three different times. A proton beam of 2.57 Me V obtained using 5UDH-II Pelletron accelerator was used for excitation of x-rays from the sample. The acquired experimental data were analyzed using the GUPIXWIN software. The results show that the SRM data and the data obtained using the PIXE technique are in good agreement.展开更多
We describe the effects of plane surface on the photo-detached electron spectra from H^(-)_(2).A z-polarized laser is used for the detachment of electrons.The detached electron flux and photodetachment cross section a...We describe the effects of plane surface on the photo-detached electron spectra from H^(-)_(2).A z-polarized laser is used for the detachment of electrons.The detached electron flux and photodetachment cross section are derived.There exists strong dependence on the distance of the H^(-)_(2) from the surface and also on the separation of atomic centers of H^(-)_(2).The results show strong oscillations for smaller values of distances,whereas for larger values the oscillating structure disappears.展开更多
The photodetachnent of a hydrogen negative ion (H-) near a partially reflecting surface with a spherical shape is investigated by a theoretical imaging method.Analytical expressions for the detached electron flux and ...The photodetachnent of a hydrogen negative ion (H-) near a partially reflecting surface with a spherical shape is investigated by a theoretical imaging method.Analytical expressions for the detached electron flux and total photodetachment cross section are derived.It is found that two parameters,i.e.curvature radius Tc and reflection parameter K,control the photodetachment spectra.Furthermore,these parameters can be used for the classification,identification and revelation of minor details like curvature of different types of surfaces.展开更多
We report the combined effects of laser polarization and curvature of the spherical surface on the detached electron spectra from H-. The Theoretical imaging method is used as a tool of investigation. The photodetachm...We report the combined effects of laser polarization and curvature of the spherical surface on the detached electron spectra from H-. The Theoretical imaging method is used as a tool of investigation. The photodetachment cross sections for various polaxization angles, radii of curvatures and inter ion surface distances axe displayed. The analysis of the spectra reveals that the laser polarization angle θL, curvature of the surface τc and inter ion surface distance d strongly affect oscillations in the spectra. Therefore, a fine control on the laser polaxization and that of curvature in the surface can be used to control oscillations in the photodetachment of negative ions.展开更多
文摘This paper describes the standardization of the proton-induced x-ray emission（PIXE） technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard reference materials（SRMs） were analyzed using this technique and the data were compared with the already known data of these certified SRMs. These samples were selected in order to cover the maximum range of elements in the periodic table. Each sample was irradiated for three different values of collected beam charges at three different times. A proton beam of 2.57 Me V obtained using 5UDH-II Pelletron accelerator was used for excitation of x-rays from the sample. The acquired experimental data were analyzed using the GUPIXWIN software. The results show that the SRM data and the data obtained using the PIXE technique are in good agreement.
文摘We describe the effects of plane surface on the photo-detached electron spectra from H^(-)_(2).A z-polarized laser is used for the detachment of electrons.The detached electron flux and photodetachment cross section are derived.There exists strong dependence on the distance of the H^(-)_(2) from the surface and also on the separation of atomic centers of H^(-)_(2).The results show strong oscillations for smaller values of distances,whereas for larger values the oscillating structure disappears.
文摘The photodetachnent of a hydrogen negative ion (H-) near a partially reflecting surface with a spherical shape is investigated by a theoretical imaging method.Analytical expressions for the detached electron flux and total photodetachment cross section are derived.It is found that two parameters,i.e.curvature radius Tc and reflection parameter K,control the photodetachment spectra.Furthermore,these parameters can be used for the classification,identification and revelation of minor details like curvature of different types of surfaces.
文摘We report the combined effects of laser polarization and curvature of the spherical surface on the detached electron spectra from H-. The Theoretical imaging method is used as a tool of investigation. The photodetachment cross sections for various polaxization angles, radii of curvatures and inter ion surface distances axe displayed. The analysis of the spectra reveals that the laser polarization angle θL, curvature of the surface τc and inter ion surface distance d strongly affect oscillations in the spectra. Therefore, a fine control on the laser polaxization and that of curvature in the surface can be used to control oscillations in the photodetachment of negative ions.
