The pellet tracking system is very important to Pellet target test station (PTS) which is being constructed atIMP[1]. We have performed several tests for this system. The pellet being tracked is a small transparent sp...The pellet tracking system is very important to Pellet target test station (PTS) which is being constructed atIMP[1]. We have performed several tests for this system. The pellet being tracked is a small transparent sphere.We have done two kinds of tests to make sure the transparent sphere could be detected by the camera.Firstly, we used a plastic rod (3.43 mm) as a target and took photos for them. Fig. 1 shows that the diameterof the rod estimated on the photos is 3.41 mm, and the error is only 0.6%. This result suggests that the cameracan be detected the target perfectly.展开更多
The pellet target system, which is often used in hadronic physics experiments, is an internal target with 4coverage for reaction productions detection[1]. The pellet will interact with the circulating ion beam perpen...The pellet target system, which is often used in hadronic physics experiments, is an internal target with 4coverage for reaction productions detection[1]. The pellet will interact with the circulating ion beam perpendicularlyin the reaction chamber. The precise determination of the reaction vertex is very helpful for the reconstruction ofthe events with short lived production particles. The pellet tracking system with other detectors can determinethe position of reaction vertex very precisely to an order of ten micrometer[2]. The pellet test station is beingconstructed at IMP, where the pellet tracking system is being built, and several experiments have been completedin IMP.展开更多
The silicon micro-strip detector was fabricated by MEMS (Micro Electro Mechanical Systems) techniques[1].According to the application requirement and the process parameters, a large amount of B+ ions at 40 keV and1.5...The silicon micro-strip detector was fabricated by MEMS (Micro Electro Mechanical Systems) techniques[1].According to the application requirement and the process parameters, a large amount of B+ ions at 40 keV and1.51014 ions/cm2 have been implanted into the wafers. It is found that more than 50% of the micro strips cannotform a functional P-N junction. Based on the suggestion of simulation results, the process of stratified implantationwas then applied with the following procedures. B+ ions were firstly implanted into the wafer at 40 keV, 21014ions/cm2, and then sequentially implanted at 20 keV, 21014 ions/cm2 into the same wafers. Preliminary testresults show that over 95% of the silicon micro-strips in this batch have a perfect P-N junction with a reverse bodyresistance larger than 500 MΩcm. The energy resolution for 5.156 MeV particles of 239Pu source is about 0.8%or even less, as shown in Fig. 1. The structure of the detectors is therefore definitely different from the designeddevices (Fig. 2(a)) shown in Fig. 1, which is more like a P-P+-N structure as shown in Fig. 2(b).展开更多
Many studies have demonstrated that the degradation of silicon detector properties in a radiation field is linearlycorrelated to the displacement damage energy[1] induced by the non-ionizing energy loss (NIEL). It has...Many studies have demonstrated that the degradation of silicon detector properties in a radiation field is linearlycorrelated to the displacement damage energy[1] induced by the non-ionizing energy loss (NIEL). It has been pointedoutthat NIEL can be incorporated into Monte Carlo transport codes to estimate the displacement damage effects[2].Fig. 1 shows the results of a SRIM simulation for 10 MeV protons injected on a double-sided silicon micro-stripdetector. It can be clearly seen that more than 95% of the energy loss can be ascribed to ionizing energy loss, whichprovides energy to excite or ionize extra nuclear electrons to generate electron-hole pairs when incident particlestraverse the detector and collide with lattice atoms. Less than 5% of energy loss is non-ionizing energy loss whichinduces lattice atom displacement damage or transforms into phonons to participate in the crystal lattice vibration.展开更多
Silicon detectors have been widely used in high energy, astrophysics and nuclear medicine due to their perfectposition resolution and energy resolution, wide linear range and quicke response time[1;2]. They are also u...Silicon detectors have been widely used in high energy, astrophysics and nuclear medicine due to their perfectposition resolution and energy resolution, wide linear range and quicke response time[1;2]. They are also used asvertex detectors and track detectors in the world nuclear physics laboratories[3]. Ion-implanted silicon decetors suchas strip decetors and have been used in experiment. A pisition-sensitive decetor, that is 33 grid silicon deterctor,is further developed for experiment purpose. It is shown in Fig. 1, which is made of nine 10 mm10 mm squaresilicons pads.展开更多
Pellet target is one of the main candidate targets in CSRm (cooler storage ring’s main ring) for hadron physics studies. Pellet speed is an important physical parameter for the target. Larger pellet speed could short...Pellet target is one of the main candidate targets in CSRm (cooler storage ring’s main ring) for hadron physics studies. Pellet speed is an important physical parameter for the target. Larger pellet speed could shorten the interacting time interval between the pellet and the cyclotron beam, and thus results in a small temperature variation for the pellet. This could make the pellet facility work in a stable condition. A fluid dynamic simulation was carried out for the pellet speed, and it was found that the maximum speed for the target pellet may be restricted to about 100 m/s even if all working parameters were set to their optimal values.展开更多
文摘The pellet tracking system is very important to Pellet target test station (PTS) which is being constructed atIMP[1]. We have performed several tests for this system. The pellet being tracked is a small transparent sphere.We have done two kinds of tests to make sure the transparent sphere could be detected by the camera.Firstly, we used a plastic rod (3.43 mm) as a target and took photos for them. Fig. 1 shows that the diameterof the rod estimated on the photos is 3.41 mm, and the error is only 0.6%. This result suggests that the cameracan be detected the target perfectly.
文摘The pellet target system, which is often used in hadronic physics experiments, is an internal target with 4coverage for reaction productions detection[1]. The pellet will interact with the circulating ion beam perpendicularlyin the reaction chamber. The precise determination of the reaction vertex is very helpful for the reconstruction ofthe events with short lived production particles. The pellet tracking system with other detectors can determinethe position of reaction vertex very precisely to an order of ten micrometer[2]. The pellet test station is beingconstructed at IMP, where the pellet tracking system is being built, and several experiments have been completedin IMP.
文摘The silicon micro-strip detector was fabricated by MEMS (Micro Electro Mechanical Systems) techniques[1].According to the application requirement and the process parameters, a large amount of B+ ions at 40 keV and1.51014 ions/cm2 have been implanted into the wafers. It is found that more than 50% of the micro strips cannotform a functional P-N junction. Based on the suggestion of simulation results, the process of stratified implantationwas then applied with the following procedures. B+ ions were firstly implanted into the wafer at 40 keV, 21014ions/cm2, and then sequentially implanted at 20 keV, 21014 ions/cm2 into the same wafers. Preliminary testresults show that over 95% of the silicon micro-strips in this batch have a perfect P-N junction with a reverse bodyresistance larger than 500 MΩcm. The energy resolution for 5.156 MeV particles of 239Pu source is about 0.8%or even less, as shown in Fig. 1. The structure of the detectors is therefore definitely different from the designeddevices (Fig. 2(a)) shown in Fig. 1, which is more like a P-P+-N structure as shown in Fig. 2(b).
文摘Many studies have demonstrated that the degradation of silicon detector properties in a radiation field is linearlycorrelated to the displacement damage energy[1] induced by the non-ionizing energy loss (NIEL). It has been pointedoutthat NIEL can be incorporated into Monte Carlo transport codes to estimate the displacement damage effects[2].Fig. 1 shows the results of a SRIM simulation for 10 MeV protons injected on a double-sided silicon micro-stripdetector. It can be clearly seen that more than 95% of the energy loss can be ascribed to ionizing energy loss, whichprovides energy to excite or ionize extra nuclear electrons to generate electron-hole pairs when incident particlestraverse the detector and collide with lattice atoms. Less than 5% of energy loss is non-ionizing energy loss whichinduces lattice atom displacement damage or transforms into phonons to participate in the crystal lattice vibration.
文摘Silicon detectors have been widely used in high energy, astrophysics and nuclear medicine due to their perfectposition resolution and energy resolution, wide linear range and quicke response time[1;2]. They are also used asvertex detectors and track detectors in the world nuclear physics laboratories[3]. Ion-implanted silicon decetors suchas strip decetors and have been used in experiment. A pisition-sensitive decetor, that is 33 grid silicon deterctor,is further developed for experiment purpose. It is shown in Fig. 1, which is made of nine 10 mm10 mm squaresilicons pads.
基金Supported by the National Natural Science Foundation of China (Grant Nos 10635080 and 10575120)
文摘Pellet target is one of the main candidate targets in CSRm (cooler storage ring’s main ring) for hadron physics studies. Pellet speed is an important physical parameter for the target. Larger pellet speed could shorten the interacting time interval between the pellet and the cyclotron beam, and thus results in a small temperature variation for the pellet. This could make the pellet facility work in a stable condition. A fluid dynamic simulation was carried out for the pellet speed, and it was found that the maximum speed for the target pellet may be restricted to about 100 m/s even if all working parameters were set to their optimal values.
