在电子显微镜中,通过记录大角非弹性散射电子能量损失谱来研究固体材料基态电子动量密度分布的方法,称为固体的电子康普顿散射技术(electron Compton scattering from solids,ECOSS)。利用该技术得到的康普顿轮廓的动量分辨率可以达到...在电子显微镜中,通过记录大角非弹性散射电子能量损失谱来研究固体材料基态电子动量密度分布的方法,称为固体的电子康普顿散射技术(electron Compton scattering from solids,ECOSS)。利用该技术得到的康普顿轮廓的动量分辨率可以达到从同步辐射光源上得到的康普顿轮廓的动量分辨率水平;而其非常短的收集时间,使利用康普顿散射对固体材料电子动量密度的系统研究成为可能。本文简要介绍了该技术的背景、实验方法、理论基础,研究进展和应用。展开更多
The evolution of the electron phase orbits based on the multi-photon nonlinear Compton scattering with the high power laser-plasma is discussed by using Kroll-Morton-Rosenbluth theory. The random evolution of the un-c...The evolution of the electron phase orbits based on the multi-photon nonlinear Compton scattering with the high power laser-plasma is discussed by using Kroll-Morton-Rosenbluth theory. The random evolution of the un-captured electron phase orbits from periodicity to non-periodicity is found after the energy has been exchanged between the electron and photons. With the increase of the absorbed photon number n by an electron,this evolution will be more and more intense, while which is rapidly decreased with the enhancement of the collision non-flexibility ξ and their initial speeds of the electrons and photons,but this evolution is lower than that in the high power laser field. When the electrons are captured by the laser field,the evolution is finished,and the electrons will stably transport,and the photons don’t provide the energy for these electrons any more.展开更多
The response of a silicon alpha detector to beta particles, electrons and photons was investigated using measurements and Monte Carlo simulations. This information is of relevance for in situ alpha spectrometry from d...The response of a silicon alpha detector to beta particles, electrons and photons was investigated using measurements and Monte Carlo simulations. This information is of relevance for in situ alpha spectrometry from different surfaces at ambient air pressure. According to the simulations, photon detection efficiencies were more than two orders of magnitude smaller than those of electrons. Photons generate signals mainly by Compton electrons. Counts originating from beta particles, electrons and photons were usually below 1 MeV in energy and no clear peaks could be identified from the measured spectra. Unequivocal identification of radionuclides emitting beta particles, electrons and photons is not possible when a mixture of different radionuclides is present in the source. However, radionuclide classification according to their emission energies appears to be possible. Surface contamination measurements will benefit from this capability.展开更多
Using the model of the inverse Compton scattering between high-energy electrons and heat-radiation photons, the influence of heat-radiating photons on multi-photon Compton scattering high-energy electrons is studied ....Using the model of the inverse Compton scattering between high-energy electrons and heat-radiation photons, the influence of heat-radiating photons on multi-photon Compton scattering high-energy electrons is studied . The results show that the energy loss, power loss, light resistance and light pressure of the high-energy electron formed by heat radiating are all proportional to the temperature T4 of the vacuum cavity of the electron,the Lorentz factor γ2 of the high-energy electrons, the scattering section of the electron and the number of photons acting at the same time with high-energy electrons. A good method for lessening the energy loss of the high-energy electron by using the one-photon Compton scattering between high-energy electrons and heat radiation photons is proposed.展开更多
Compton scattering is used very widely. In this article, we depict an overall picture for its applications which are based on two basic theories. The first is the electron densitometry theory related to electron densi...Compton scattering is used very widely. In this article, we depict an overall picture for its applications which are based on two basic theories. The first is the electron densitometry theory related to electron density. According to this theory its applications are in two fields: one is Compton scatter densitometry (CSD), the other is Compton scatter imaging (CSI). The second technique involves the electron momentum distribution and Compton profile. Applications of this technique are mainly the Compton profile analysis (CPA) and the Compton profile or the electron momentum distribution in physics and chemistry. Future research fields are suggested according to the current situation and limits of this technique and a promising prospect is unfolded.展开更多
Using the single particle theory and the non-flexibility collision model of electron and photon, the influence of the uncaptured electrons on the energy conversion efficiency of multi-photon nonlinear Compton scatteri...Using the single particle theory and the non-flexibility collision model of electron and photon, the influence of the uncaptured electrons on the energy conversion efficiency of multi-photon nonlinear Compton scattering in the extra stationary laser-plasma is investigated. It shows that in extra stationary laser-plasma,the uncaptured electrons make the Δω of the scattering frequency of the multi-photon Compton fall down with the increases of the incident radiation electron speed,the materials of the incident collision of electron and photon, and the number of the photons which work with the electrons at the same time. Under the modulation of the uncaptured electrons to the laser field, the energy conversion efficiency between electrons and photons will fall down with the increase of the electron incident radiation speed, using the low-power electrons for incident source, the loss can be efficiently reduced.展开更多
Blazars are subclass of AGN (active galactic nuclei) with relativistic jet that is pointing in the general direction of the earth. The energy flux in the jet is about (10^44-10^47) erg/s. The γ-rays in the energy...Blazars are subclass of AGN (active galactic nuclei) with relativistic jet that is pointing in the general direction of the earth. The energy flux in the jet is about (10^44-10^47) erg/s. The γ-rays in the energy range 10 GeV-10 TeV emanating from blazar are examined and their effect on the IGM (intergalactic medium) is studied. The γ-ray emission is considered as due to inverse Compton scattering of relativistic electrons. There appears to be a gamma ray flux from blazar above 10 GeV having a line intensity of 1.5 × 10^-4 cm^-2 s^-1 sr^-1. The IGM is measured to large distances and it is found to be clumpy. It is found that at higher redshifl the density of IGM increases. The cosmological density parameter measured is found to lie within the suggested limit of 0.03 at redshift z = 3 for background intensity of radiation 10^-24 W·m^-2·Hz^-1·sr^-1. The iso-ΩIGM curve shows a kink in its profile which might be significant at the particular value of z equal to 2. Some more detailed studies are required for understanding the distribution of intergalactic medium at the unstable point at z = 2 as shown in inverse Compton radiation.展开更多
文摘在电子显微镜中,通过记录大角非弹性散射电子能量损失谱来研究固体材料基态电子动量密度分布的方法,称为固体的电子康普顿散射技术(electron Compton scattering from solids,ECOSS)。利用该技术得到的康普顿轮廓的动量分辨率可以达到从同步辐射光源上得到的康普顿轮廓的动量分辨率水平;而其非常短的收集时间,使利用康普顿散射对固体材料电子动量密度的系统研究成为可能。本文简要介绍了该技术的背景、实验方法、理论基础,研究进展和应用。
基金Natural Science Basic Research Project for Education Department of Henan Province(20011400006)
文摘The evolution of the electron phase orbits based on the multi-photon nonlinear Compton scattering with the high power laser-plasma is discussed by using Kroll-Morton-Rosenbluth theory. The random evolution of the un-captured electron phase orbits from periodicity to non-periodicity is found after the energy has been exchanged between the electron and photons. With the increase of the absorbed photon number n by an electron,this evolution will be more and more intense, while which is rapidly decreased with the enhancement of the collision non-flexibility ξ and their initial speeds of the electrons and photons,but this evolution is lower than that in the high power laser field. When the electrons are captured by the laser field,the evolution is finished,and the electrons will stably transport,and the photons don’t provide the energy for these electrons any more.
文摘The response of a silicon alpha detector to beta particles, electrons and photons was investigated using measurements and Monte Carlo simulations. This information is of relevance for in situ alpha spectrometry from different surfaces at ambient air pressure. According to the simulations, photon detection efficiencies were more than two orders of magnitude smaller than those of electrons. Photons generate signals mainly by Compton electrons. Counts originating from beta particles, electrons and photons were usually below 1 MeV in energy and no clear peaks could be identified from the measured spectra. Unequivocal identification of radionuclides emitting beta particles, electrons and photons is not possible when a mixture of different radionuclides is present in the source. However, radionuclide classification according to their emission energies appears to be possible. Surface contamination measurements will benefit from this capability.
基金Natural Science Foundation of Zhumadian City(058002)
文摘Using the model of the inverse Compton scattering between high-energy electrons and heat-radiation photons, the influence of heat-radiating photons on multi-photon Compton scattering high-energy electrons is studied . The results show that the energy loss, power loss, light resistance and light pressure of the high-energy electron formed by heat radiating are all proportional to the temperature T4 of the vacuum cavity of the electron,the Lorentz factor γ2 of the high-energy electrons, the scattering section of the electron and the number of photons acting at the same time with high-energy electrons. A good method for lessening the energy loss of the high-energy electron by using the one-photon Compton scattering between high-energy electrons and heat radiation photons is proposed.
基金Funded by the project of Chongqing Normal University (05XSY002).
文摘Compton scattering is used very widely. In this article, we depict an overall picture for its applications which are based on two basic theories. The first is the electron densitometry theory related to electron density. According to this theory its applications are in two fields: one is Compton scatter densitometry (CSD), the other is Compton scatter imaging (CSI). The second technique involves the electron momentum distribution and Compton profile. Applications of this technique are mainly the Compton profile analysis (CPA) and the Compton profile or the electron momentum distribution in physics and chemistry. Future research fields are suggested according to the current situation and limits of this technique and a promising prospect is unfolded.
文摘Using the single particle theory and the non-flexibility collision model of electron and photon, the influence of the uncaptured electrons on the energy conversion efficiency of multi-photon nonlinear Compton scattering in the extra stationary laser-plasma is investigated. It shows that in extra stationary laser-plasma,the uncaptured electrons make the Δω of the scattering frequency of the multi-photon Compton fall down with the increases of the incident radiation electron speed,the materials of the incident collision of electron and photon, and the number of the photons which work with the electrons at the same time. Under the modulation of the uncaptured electrons to the laser field, the energy conversion efficiency between electrons and photons will fall down with the increase of the electron incident radiation speed, using the low-power electrons for incident source, the loss can be efficiently reduced.
文摘Blazars are subclass of AGN (active galactic nuclei) with relativistic jet that is pointing in the general direction of the earth. The energy flux in the jet is about (10^44-10^47) erg/s. The γ-rays in the energy range 10 GeV-10 TeV emanating from blazar are examined and their effect on the IGM (intergalactic medium) is studied. The γ-ray emission is considered as due to inverse Compton scattering of relativistic electrons. There appears to be a gamma ray flux from blazar above 10 GeV having a line intensity of 1.5 × 10^-4 cm^-2 s^-1 sr^-1. The IGM is measured to large distances and it is found to be clumpy. It is found that at higher redshifl the density of IGM increases. The cosmological density parameter measured is found to lie within the suggested limit of 0.03 at redshift z = 3 for background intensity of radiation 10^-24 W·m^-2·Hz^-1·sr^-1. The iso-ΩIGM curve shows a kink in its profile which might be significant at the particular value of z equal to 2. Some more detailed studies are required for understanding the distribution of intergalactic medium at the unstable point at z = 2 as shown in inverse Compton radiation.