Traditional plastic scintillator has respectively low gamma energy resolution.Space radiation detection need the plastic scintillator to keep a relatively better energy resolution for gamma.Thus we did experiments to ...Traditional plastic scintillator has respectively low gamma energy resolution.Space radiation detection need the plastic scintillator to keep a relatively better energy resolution for gamma.Thus we did experiments to study how to get it enhanced by adding light guider and chamfer.A 9000 Bq radioactive source 60 Co has been utilized to make the experiment and results came that when keeping other conditions same,the height of poly methyl methacrylate(PMMA)light guider changes from 12 mm to 40 mm and the energy resolutions varied from 72.3%to63.5% respectively.Furthermore,another contrast experiment was made to decide whether plastic scintillator with light guiders or integrated chamfer can get better energy resolution.In conclusion the plastic scintillator with integrated chamfer got 55.0%.Through the study of adding light guider or chamfer to plastic scintillator,the gamma energy resolution has been improved greatly from 72.3%to 55.0%.展开更多
When solid surface is bombarded by energetic projectile ions, a fraction of the sputtered particles leaves the surface in electronically excited states. The optical emission in front of the target surface is due to th...When solid surface is bombarded by energetic projectile ions, a fraction of the sputtered particles leaves the surface in electronically excited states. The optical emission in front of the target surface is due to the radiative decay of these sputtered particles[1;2]. The optical emission identifies the target by measurement of wavelength.展开更多
The study on ion-solid collisions has important significances not only for fundamental researches but also for technical applications, like ion-beam modification and analysis of surfaces[1]. So far, K-shell ionization...The study on ion-solid collisions has important significances not only for fundamental researches but also for technical applications, like ion-beam modification and analysis of surfaces[1]. So far, K-shell ionization has beenmost widely studied for large range of projectile number and incident energy[2;3]. However, even today, a complete theory that can predict K-shell vacancy production for all collision systems in different velocities is still lacking, especially at an intermediate energy.展开更多
GaAs is a direct band gap semiconductor,which makes it a very useful material for the manufacture of light emitting diodes and semiconductor lasers.Impact of highly charged ions(HCI)on semiconductor solid surfaces giv...GaAs is a direct band gap semiconductor,which makes it a very useful material for the manufacture of light emitting diodes and semiconductor lasers.Impact of highly charged ions(HCI)on semiconductor solid surfaces gives rise to visible light emission from excited sputtered atoms.This work measured visible light emission from the monocrystal GaAs(100)surface bombarded by highly charged Xe^q+(6≤q≤23)as a function of charged state of the incident ion.The experiment was carried out at the 320 kV platform for multi-discipline research with HCIs in the Institute of Modern Physics,Chinese Academy of Sciences.展开更多
Slow highly charged ions(HCIs)interaction with the solid also provides information such as electron configuration,multi-interaction,ionization,excitation and charge transfer for the basic research[1??3].What is more,t...Slow highly charged ions(HCIs)interaction with the solid also provides information such as electron configuration,multi-interaction,ionization,excitation and charge transfer for the basic research[1??3].What is more,the understanding on the heavy HCI structure and relevant collision processes has a special meaning for inertial confinement fusion(ICF)research.Up to now,many experiments or theories in ion-solid collisions focus on the investigation of secondary electrons,sputtering ion or characteristic X-rays emission by the slow projectile[4].展开更多
In our previous work[1],using a pair of grooved SiO2 parallel plates,we had obtained stably guided electron beams without energy loss in the incident energy range of 8002 000 V.The very high-current(up to tens or hun...In our previous work[1],using a pair of grooved SiO2 parallel plates,we had obtained stably guided electron beams without energy loss in the incident energy range of 8002 000 V.The very high-current(up to tens or hundreds of nA/mm2)electron beams were adopted.A 128-strip electrode array with a 128-channel picoammeter system[2],combined with an electrostatic deflector were employed to monitor the transmitted electron beams.To better understanding the guiding processes of electron beams passing through the insulting plates,several grooved parallel plates made by different insulating materials were adopted to study the dependence relative to the guiding beams on the conductivities of these materials.As shown in Fig.展开更多
采用不同材质的刻槽绝缘平行板,包括高纯度石英玻璃、聚四氟乙烯(Teflon)、酚醛树脂(电木)和聚甲醛板(赛钢板),并在15 p A/mm^2~14.3 n A/mm^2范围内改变入射流强,利用1 500 e V电子束入射上述绝缘平行板,实验研究了上述平行板对电子...采用不同材质的刻槽绝缘平行板,包括高纯度石英玻璃、聚四氟乙烯(Teflon)、酚醛树脂(电木)和聚甲醛板(赛钢板),并在15 p A/mm^2~14.3 n A/mm^2范围内改变入射流强,利用1 500 e V电子束入射上述绝缘平行板,实验研究了上述平行板对电子束的导向行为。实验发现,上述电子束通过上述平行板时存在明显的导向现象,其导向行为与束流流强和绝缘材质无关。据此,可排除绝缘平行板内表面沉积电荷自组织充放电过程中,以绝缘材料的面电阻和体电阻对地泄放的线性形式放电过程。展开更多
基金supported by the National Natural Science Foundation of China including Research on the Technology of Fast Neutron Location Sensitive Detector Based on GEM and Data Acquisition(No.11575073)the Space Neutron Telescope Detection Technology(No.11775114)
文摘Traditional plastic scintillator has respectively low gamma energy resolution.Space radiation detection need the plastic scintillator to keep a relatively better energy resolution for gamma.Thus we did experiments to study how to get it enhanced by adding light guider and chamfer.A 9000 Bq radioactive source 60 Co has been utilized to make the experiment and results came that when keeping other conditions same,the height of poly methyl methacrylate(PMMA)light guider changes from 12 mm to 40 mm and the energy resolutions varied from 72.3%to63.5% respectively.Furthermore,another contrast experiment was made to decide whether plastic scintillator with light guiders or integrated chamfer can get better energy resolution.In conclusion the plastic scintillator with integrated chamfer got 55.0%.Through the study of adding light guider or chamfer to plastic scintillator,the gamma energy resolution has been improved greatly from 72.3%to 55.0%.
文摘When solid surface is bombarded by energetic projectile ions, a fraction of the sputtered particles leaves the surface in electronically excited states. The optical emission in front of the target surface is due to the radiative decay of these sputtered particles[1;2]. The optical emission identifies the target by measurement of wavelength.
文摘The study on ion-solid collisions has important significances not only for fundamental researches but also for technical applications, like ion-beam modification and analysis of surfaces[1]. So far, K-shell ionization has beenmost widely studied for large range of projectile number and incident energy[2;3]. However, even today, a complete theory that can predict K-shell vacancy production for all collision systems in different velocities is still lacking, especially at an intermediate energy.
文摘GaAs is a direct band gap semiconductor,which makes it a very useful material for the manufacture of light emitting diodes and semiconductor lasers.Impact of highly charged ions(HCI)on semiconductor solid surfaces gives rise to visible light emission from excited sputtered atoms.This work measured visible light emission from the monocrystal GaAs(100)surface bombarded by highly charged Xe^q+(6≤q≤23)as a function of charged state of the incident ion.The experiment was carried out at the 320 kV platform for multi-discipline research with HCIs in the Institute of Modern Physics,Chinese Academy of Sciences.
文摘Slow highly charged ions(HCIs)interaction with the solid also provides information such as electron configuration,multi-interaction,ionization,excitation and charge transfer for the basic research[1??3].What is more,the understanding on the heavy HCI structure and relevant collision processes has a special meaning for inertial confinement fusion(ICF)research.Up to now,many experiments or theories in ion-solid collisions focus on the investigation of secondary electrons,sputtering ion or characteristic X-rays emission by the slow projectile[4].
文摘In our previous work[1],using a pair of grooved SiO2 parallel plates,we had obtained stably guided electron beams without energy loss in the incident energy range of 8002 000 V.The very high-current(up to tens or hundreds of nA/mm2)electron beams were adopted.A 128-strip electrode array with a 128-channel picoammeter system[2],combined with an electrostatic deflector were employed to monitor the transmitted electron beams.To better understanding the guiding processes of electron beams passing through the insulting plates,several grooved parallel plates made by different insulating materials were adopted to study the dependence relative to the guiding beams on the conductivities of these materials.As shown in Fig.
文摘采用不同材质的刻槽绝缘平行板,包括高纯度石英玻璃、聚四氟乙烯(Teflon)、酚醛树脂(电木)和聚甲醛板(赛钢板),并在15 p A/mm^2~14.3 n A/mm^2范围内改变入射流强,利用1 500 e V电子束入射上述绝缘平行板,实验研究了上述平行板对电子束的导向行为。实验发现,上述电子束通过上述平行板时存在明显的导向现象,其导向行为与束流流强和绝缘材质无关。据此,可排除绝缘平行板内表面沉积电荷自组织充放电过程中,以绝缘材料的面电阻和体电阻对地泄放的线性形式放电过程。