The Experts below are selected from a list of 905841 Experts worldwide ranked by ideXlab platform
H. Tsuchiya - One of the best experts on this subject based on the ideXlab platform.
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upper limits on the solar Neutron flux at the yangbajing Neutron monitor from batse detected solar flares
Astronomy and Astrophysics, 2007Co-Authors: H. Tsuchiya, H Miyasaka, E Takahashi, S Shimoda, Y Yamada, Izumi Kondo, Kazuo Makishima, H B Hu, Y Q Tang, J ZhangAbstract:Aims. The purpose of this work is to search the data from Yangbajing Neutron monitor obtained between 1998 October and 2000 June for the solar Neutrons associated with solar flares. Methods. Using the onset times of 166 BATSE-detected flares with the GOES peak flux (1-8 angstrom) higher than 1.0 x 10(-5) Wm(-2), we prepared a light curve of the Yangbajing Neutron monitor for each flare, spanning +/-1.5 h from the BATSE onset time. Based on the light curves, a systematic search for solar Neutrons in energies above 100 MeV from the 166 flares was performed. No statistically significant signals due to solar Neutrons were found. Therefore, we put upper limits on the >= 100 MeV solar-Neutron flux for 18 events consisting of 2 X and 16 M class flares. The calculation assumed a power-law shaped Neutron energy spectrum and three types of Neutron emission profiles at the Sun. Results. Compared with the other positive Neutron detections associated with X-class flares, typical 95% confidence level upper limits for the two X-class flares are found to be comparable to the lowest and second lowest Neutron fluxes at the top of the atmosphere. In addition, the upper limits for M-class flares scatter in the range of 10(-2) to 1 Neutrons cm(-2) s(-1). This provides the first upper limits on the solar-Neutron flux from M-class solar flares, using space observatories, as well as ground-based Neutron monitors.
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upper limits on high energy solar Neutrons from satellite detected flares with the yangbajing Neutron monitor
2007Co-Authors: H. Tsuchiya, H Miyasaka, E Takahashi, S Shimoda, Y Yamada, Izumi Kondo, H B Hu, Y Q Tang, J Zhang, H LuAbstract:We report a systematic search for solar Neutrons using the Yangbajing Neutron monitor. Making use of the onset times of >� 25 keV hard x-ray emissions detected by BATSE, we search the Yangbajing Neutron monitor data for possible count enhancements due to solar Neutrons from the BATSE- detected flares. As a result, statistically significant sign als from individual flares were not found. We hence deduced 99 % confidence level upper limits on > 50 MeV solar-Neutron flux at 1 AU, comparing them with absolute Neutron fluxes deduced from past positive detections.
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Soft errors in SRAM devices induced by high energy Neutrons, thermal Neutrons and alpha particles
Digest. International Electron Devices Meeting, 2002Co-Authors: H. Kobayashi, K. Shiraishi, H. Tsuchiya, M. Motoyoshi, H. Usuki, Y. Nagai, K. Takahisa, Toshimasa Yoshiie, Y. Sakurai, T. IshizakiAbstract:We measured the soft error rates (SER) of SRAM devices in several field tests, and obtained SERs induced independently by high energy Neutrons, thermal Neutrons and alpha particles. It was found that the thermal Neutron induced SER was approximately three times larger than the high energy Neutron induced SER in 0.18 /spl mu/m 8M SRAMs, and that the alpha particle induced SER was negligible. We also performed accelerated tests for thermal Neutrons using a nuclear reactor, and found that the thermal Neutron induced SER can be reduced by factors of up to several hundreds by using thermal Neutron shield sheets or by eliminating BPSG layers.
J Zhang - One of the best experts on this subject based on the ideXlab platform.
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upper limits on the solar Neutron flux at the yangbajing Neutron monitor from batse detected solar flares
Astronomy and Astrophysics, 2007Co-Authors: H. Tsuchiya, H Miyasaka, E Takahashi, S Shimoda, Y Yamada, Izumi Kondo, Kazuo Makishima, H B Hu, Y Q Tang, J ZhangAbstract:Aims. The purpose of this work is to search the data from Yangbajing Neutron monitor obtained between 1998 October and 2000 June for the solar Neutrons associated with solar flares. Methods. Using the onset times of 166 BATSE-detected flares with the GOES peak flux (1-8 angstrom) higher than 1.0 x 10(-5) Wm(-2), we prepared a light curve of the Yangbajing Neutron monitor for each flare, spanning +/-1.5 h from the BATSE onset time. Based on the light curves, a systematic search for solar Neutrons in energies above 100 MeV from the 166 flares was performed. No statistically significant signals due to solar Neutrons were found. Therefore, we put upper limits on the >= 100 MeV solar-Neutron flux for 18 events consisting of 2 X and 16 M class flares. The calculation assumed a power-law shaped Neutron energy spectrum and three types of Neutron emission profiles at the Sun. Results. Compared with the other positive Neutron detections associated with X-class flares, typical 95% confidence level upper limits for the two X-class flares are found to be comparable to the lowest and second lowest Neutron fluxes at the top of the atmosphere. In addition, the upper limits for M-class flares scatter in the range of 10(-2) to 1 Neutrons cm(-2) s(-1). This provides the first upper limits on the solar-Neutron flux from M-class solar flares, using space observatories, as well as ground-based Neutron monitors.
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upper limits on high energy solar Neutrons from satellite detected flares with the yangbajing Neutron monitor
2007Co-Authors: H. Tsuchiya, H Miyasaka, E Takahashi, S Shimoda, Y Yamada, Izumi Kondo, H B Hu, Y Q Tang, J Zhang, H LuAbstract:We report a systematic search for solar Neutrons using the Yangbajing Neutron monitor. Making use of the onset times of >� 25 keV hard x-ray emissions detected by BATSE, we search the Yangbajing Neutron monitor data for possible count enhancements due to solar Neutrons from the BATSE- detected flares. As a result, statistically significant sign als from individual flares were not found. We hence deduced 99 % confidence level upper limits on > 50 MeV solar-Neutron flux at 1 AU, comparing them with absolute Neutron fluxes deduced from past positive detections.
A Yamaguchi - One of the best experts on this subject based on the ideXlab platform.
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observation of ultracold Neutron production by 9 a cold Neutrons in superfluid helium
Physical Review Letters, 1992Co-Authors: H Yoshiki, K Sakai, M Ogura, T Kawai, Y Masuda, T Nakajima, T Takayama, Shinji Tanaka, A YamaguchiAbstract:Using velocity-analyzed cold Neutrons we observed the production of ultracold Neutrons in superfluid 4 He at 0.45 to 1.5 K. Ultracold Neutrons are produced for an incident Neutron wavelength of 8.78±0.06 A which agrees with the single-phonon emission theory. The temperature variation of the ultracold-Neutron storage lifetime is also discussed
H Yoshiki - One of the best experts on this subject based on the ideXlab platform.
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observation of ultracold Neutron production by 9 a cold Neutrons in superfluid helium
Physical Review Letters, 1992Co-Authors: H Yoshiki, K Sakai, M Ogura, T Kawai, Y Masuda, T Nakajima, T Takayama, Shinji Tanaka, A YamaguchiAbstract:Using velocity-analyzed cold Neutrons we observed the production of ultracold Neutrons in superfluid 4 He at 0.45 to 1.5 K. Ultracold Neutrons are produced for an incident Neutron wavelength of 8.78±0.06 A which agrees with the single-phonon emission theory. The temperature variation of the ultracold-Neutron storage lifetime is also discussed
H B Hu - One of the best experts on this subject based on the ideXlab platform.
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upper limits on the solar Neutron flux at the yangbajing Neutron monitor from batse detected solar flares
Astronomy and Astrophysics, 2007Co-Authors: H. Tsuchiya, H Miyasaka, E Takahashi, S Shimoda, Y Yamada, Izumi Kondo, Kazuo Makishima, H B Hu, Y Q Tang, J ZhangAbstract:Aims. The purpose of this work is to search the data from Yangbajing Neutron monitor obtained between 1998 October and 2000 June for the solar Neutrons associated with solar flares. Methods. Using the onset times of 166 BATSE-detected flares with the GOES peak flux (1-8 angstrom) higher than 1.0 x 10(-5) Wm(-2), we prepared a light curve of the Yangbajing Neutron monitor for each flare, spanning +/-1.5 h from the BATSE onset time. Based on the light curves, a systematic search for solar Neutrons in energies above 100 MeV from the 166 flares was performed. No statistically significant signals due to solar Neutrons were found. Therefore, we put upper limits on the >= 100 MeV solar-Neutron flux for 18 events consisting of 2 X and 16 M class flares. The calculation assumed a power-law shaped Neutron energy spectrum and three types of Neutron emission profiles at the Sun. Results. Compared with the other positive Neutron detections associated with X-class flares, typical 95% confidence level upper limits for the two X-class flares are found to be comparable to the lowest and second lowest Neutron fluxes at the top of the atmosphere. In addition, the upper limits for M-class flares scatter in the range of 10(-2) to 1 Neutrons cm(-2) s(-1). This provides the first upper limits on the solar-Neutron flux from M-class solar flares, using space observatories, as well as ground-based Neutron monitors.
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upper limits on high energy solar Neutrons from satellite detected flares with the yangbajing Neutron monitor
2007Co-Authors: H. Tsuchiya, H Miyasaka, E Takahashi, S Shimoda, Y Yamada, Izumi Kondo, H B Hu, Y Q Tang, J Zhang, H LuAbstract:We report a systematic search for solar Neutrons using the Yangbajing Neutron monitor. Making use of the onset times of >� 25 keV hard x-ray emissions detected by BATSE, we search the Yangbajing Neutron monitor data for possible count enhancements due to solar Neutrons from the BATSE- detected flares. As a result, statistically significant sign als from individual flares were not found. We hence deduced 99 % confidence level upper limits on > 50 MeV solar-Neutron flux at 1 AU, comparing them with absolute Neutron fluxes deduced from past positive detections.
