It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions.We have experimentally investigated2H(d,...It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions.We have experimentally investigated2H(d,p)3H,one of the most crucial reactions in big bang nucleosynthesis models,at the Shenguang-Ⅱlaser facility.In this work,we present a new calibration of CR-39 solidstate track detectors,which are widely employed as the main diagnostics in this type of fusion reaction experiment.We measure the dependence of the track diameter on the proton energy.It is found that the track diameters of protons with different energies are likely to be identical.We propose that in this case,the energy of the reaction products can be obtained by considering both the diameters and gray levels of these tracks.The present results would be very helpful for analyzing the2 H(d,p)3H reaction products recorded with the same batch of CR-39 solid-state track detectors.展开更多
In the present work, we have measured the radon gas concentrations in tap water samples are taken directly from drinking tap water in sites houses being carried in Thi-Qar governorate by using nuclear track detector (...In the present work, we have measured the radon gas concentrations in tap water samples are taken directly from drinking tap water in sites houses being carried in Thi-Qar governorate by using nuclear track detector (CR-39). The results of measurements have shown that the highest average radon concentration in water samples is found in AL-Refai region which is equal to (0.223 ± 0.03 Bq/L), while the lowest average radon gas concentration is found in AL-Fajr region which is equal to (0.108 ± 0.01 Bq/L), with an average value of (0.175 ± 0.03 Bq/L). The highest value of annual effective dose (AED) in tap water samples is found in AL-Refai region, which is equal to (0.814 μSv/y), while the lowest value of (AED) is found in AL-Fajr region which is equal to (0.394 μSv/y), with an average value of (0.640 ± 0.1 μSv/y). The present results have shown that radon gas concentrations in tap water samples are less than the recommended international value (11.1 Bq/L). There for tap water in all the studied sites in Thi-Qar governorate is safe as for as radon concentration being concerned.展开更多
The present study focuses on determination of alpha particles concentration in different samples of toothpaste by using nuclear track detector (CR-39). Nine samples of toothpaste have been collected from local Iraqi m...The present study focuses on determination of alpha particles concentration in different samples of toothpaste by using nuclear track detector (CR-39). Nine samples of toothpaste have been collected from local Iraqi markets in Babylon Province. These samples have been chosen according to their most commonly use in Babylon Province. The samples were kept with CR-39 detector for six weeks period and then etched by 6.25 N of NaOH solution at temperature of 60°C for 5 hours. The results of the present work show that Sample 3 (Frosty) found to have a high alpha concentration about four times compared with Sample 4 (Aquafresh) and about 2 - 3 times compared with other samples.展开更多
The aim of this paper is to determine the maximum values of the track length (Lmax) of alpha particles in Nuclear Track Detector (type CR-39) using a new method by taking the relation between the etching time and the ...The aim of this paper is to determine the maximum values of the track length (Lmax) of alpha particles in Nuclear Track Detector (type CR-39) using a new method by taking the relation between the etching time and the diameter square of alpha particle with different energies at constant bulk etch rate VB (1.45 μm/hr) by using TRACK_TEST program from Brun et al. function and Yu et al. function. Using the new equation, the maximum values of the track lengths of alpha particles measured in CR-39 detector have been found to be in a good agreement with the values measured by using Brun et al. function and Yu et al. function in TRACK_TEST program.展开更多
The potential of the high resolution nuclear track detector (NTD) CR-39 is examined carefully for the measurement of relativistic nuclear projectile fragmentation cross sections and studies of related processes using ...The potential of the high resolution nuclear track detector (NTD) CR-39 is examined carefully for the measurement of relativistic nuclear projectile fragmentation cross sections and studies of related processes using the experience of many years of such measurements. The charge resolution and the charge resolving power of CR-39 detectors for the measurements of 158 A GeV 207Pb projectiles and their fragments are presented. Exposures of target-detector stacks, the chemical etching procedure and the nuclear track measurements are described in detail discussing precautions and possible errors. The procedures discussed are also valid for other NTDs. A comparison with electronic active detectors is also made considering important detection and measurement aspects. An experimental design proposing the co-use of NTDs with in-use active detectors is described.展开更多
Background Changing the distance between a sample and an exposed solid-state nuclear track detector affects the number of alpha tracks recorded by the detector.This concept had been used to distinguish high-energy alp...Background Changing the distance between a sample and an exposed solid-state nuclear track detector affects the number of alpha tracks recorded by the detector.This concept had been used to distinguish high-energy alpha particles by computing the alpha emission rate at two distances(0 and 2 cm)from animal bone ash.Materials and methods Two Cr-39 detectors were placed in a container with bone ash inside to measure the alpha emission rate when the detectors were in contact with the ash and hung at a distance of 2 cm from the ash.Results The alpha emission rate was found to be 62.7×10^(−4) Bq cm^(−2) when the detector was in contact with the sample(a small exposure area)and 324.4×10^(−4) Bq cm^(−2) when the sample was placed 2 cm away(a larger exposure area).A mathematical equalization of the exposure areas was conducted(the area of the detector exposed to the alpha emitter sample at a distance of 2 cm was equalized to the area exposed when in contact with the sample).After equalization,a reduction in the average value of the alpha emission rate from 324.4×10^(−4) to 17.4×10^(−4) Bq cm^(−2) was observed.Conclusion The increase in distance between the sample and the detector allowed only high-energy alpha particles with a range greater than the traveled distance to reach the detector.Thus,this system can distinguish the type and number of nuclides in the sample by changing the distance between the detector and the sample according to each nucleus range.Additionally,the results show that the alpha emission rates in these bone samples are higher than the local values.展开更多
基金This work was supported by the National Key Research and Development Project(No.2016YFA0400502)the National Natural Science Foundation of China(No.11775312).
文摘It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions.We have experimentally investigated2H(d,p)3H,one of the most crucial reactions in big bang nucleosynthesis models,at the Shenguang-Ⅱlaser facility.In this work,we present a new calibration of CR-39 solidstate track detectors,which are widely employed as the main diagnostics in this type of fusion reaction experiment.We measure the dependence of the track diameter on the proton energy.It is found that the track diameters of protons with different energies are likely to be identical.We propose that in this case,the energy of the reaction products can be obtained by considering both the diameters and gray levels of these tracks.The present results would be very helpful for analyzing the2 H(d,p)3H reaction products recorded with the same batch of CR-39 solid-state track detectors.
文摘In the present work, we have measured the radon gas concentrations in tap water samples are taken directly from drinking tap water in sites houses being carried in Thi-Qar governorate by using nuclear track detector (CR-39). The results of measurements have shown that the highest average radon concentration in water samples is found in AL-Refai region which is equal to (0.223 ± 0.03 Bq/L), while the lowest average radon gas concentration is found in AL-Fajr region which is equal to (0.108 ± 0.01 Bq/L), with an average value of (0.175 ± 0.03 Bq/L). The highest value of annual effective dose (AED) in tap water samples is found in AL-Refai region, which is equal to (0.814 μSv/y), while the lowest value of (AED) is found in AL-Fajr region which is equal to (0.394 μSv/y), with an average value of (0.640 ± 0.1 μSv/y). The present results have shown that radon gas concentrations in tap water samples are less than the recommended international value (11.1 Bq/L). There for tap water in all the studied sites in Thi-Qar governorate is safe as for as radon concentration being concerned.
文摘The present study focuses on determination of alpha particles concentration in different samples of toothpaste by using nuclear track detector (CR-39). Nine samples of toothpaste have been collected from local Iraqi markets in Babylon Province. These samples have been chosen according to their most commonly use in Babylon Province. The samples were kept with CR-39 detector for six weeks period and then etched by 6.25 N of NaOH solution at temperature of 60°C for 5 hours. The results of the present work show that Sample 3 (Frosty) found to have a high alpha concentration about four times compared with Sample 4 (Aquafresh) and about 2 - 3 times compared with other samples.
文摘The aim of this paper is to determine the maximum values of the track length (Lmax) of alpha particles in Nuclear Track Detector (type CR-39) using a new method by taking the relation between the etching time and the diameter square of alpha particle with different energies at constant bulk etch rate VB (1.45 μm/hr) by using TRACK_TEST program from Brun et al. function and Yu et al. function. Using the new equation, the maximum values of the track lengths of alpha particles measured in CR-39 detector have been found to be in a good agreement with the values measured by using Brun et al. function and Yu et al. function in TRACK_TEST program.
文摘The potential of the high resolution nuclear track detector (NTD) CR-39 is examined carefully for the measurement of relativistic nuclear projectile fragmentation cross sections and studies of related processes using the experience of many years of such measurements. The charge resolution and the charge resolving power of CR-39 detectors for the measurements of 158 A GeV 207Pb projectiles and their fragments are presented. Exposures of target-detector stacks, the chemical etching procedure and the nuclear track measurements are described in detail discussing precautions and possible errors. The procedures discussed are also valid for other NTDs. A comparison with electronic active detectors is also made considering important detection and measurement aspects. An experimental design proposing the co-use of NTDs with in-use active detectors is described.
文摘Background Changing the distance between a sample and an exposed solid-state nuclear track detector affects the number of alpha tracks recorded by the detector.This concept had been used to distinguish high-energy alpha particles by computing the alpha emission rate at two distances(0 and 2 cm)from animal bone ash.Materials and methods Two Cr-39 detectors were placed in a container with bone ash inside to measure the alpha emission rate when the detectors were in contact with the ash and hung at a distance of 2 cm from the ash.Results The alpha emission rate was found to be 62.7×10^(−4) Bq cm^(−2) when the detector was in contact with the sample(a small exposure area)and 324.4×10^(−4) Bq cm^(−2) when the sample was placed 2 cm away(a larger exposure area).A mathematical equalization of the exposure areas was conducted(the area of the detector exposed to the alpha emitter sample at a distance of 2 cm was equalized to the area exposed when in contact with the sample).After equalization,a reduction in the average value of the alpha emission rate from 324.4×10^(−4) to 17.4×10^(−4) Bq cm^(−2) was observed.Conclusion The increase in distance between the sample and the detector allowed only high-energy alpha particles with a range greater than the traveled distance to reach the detector.Thus,this system can distinguish the type and number of nuclides in the sample by changing the distance between the detector and the sample according to each nucleus range.Additionally,the results show that the alpha emission rates in these bone samples are higher than the local values.
