Project/Area Number |
15540290
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Particle/Nuclear/Cosmic ray/Astro physics
|
Research Institution | Fukui University of Technology |
Principal Investigator |
NAGANO Motohiko Fukui University of Technology, Professor, 工学部, 教授 (00013384)
|
Co-Investigator(Kenkyū-buntansha) |
KOBAYAKAWA Keizo Fukui University of Technology, Professor, 工学部(平15年度), 教授 (00031287)
|
Project Period (FY) |
2003 – 2004
|
Project Status |
Completed (Fiscal Year 2004)
|
Budget Amount *help |
¥2,600,000 (Direct Cost: ¥2,600,000)
Fiscal Year 2004: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2003: ¥1,800,000 (Direct Cost: ¥1,800,000)
|
Keywords | ultrahigh-energy cosmic rays / extensive air shower / fluorescence efficiency / AGASA / HiRes / EUSO |
Research Abstract |
The air fluorescence technique is used to detect ultrahigh-energy cosmic rays, and to estimate their energy. Of fundamental importance is the photon yield due to excitation by electrons in air of various densities and temperatures. The purposes of this research are : 1. Using a ^<90>Sr β source to study the pressure dependence of photon yields and the life times of the excited states, for radiation in nitrogen and dry air. 2. By applying the experimental results to the on-going experiments such as HiRes and Auger, and the planed project from the space-station such as EUSO, to estimate the systematic errors in energy determination of cosmic rays. For (1), the photon yields in 15 wave bands between 300nm and 430nm have been determined. The total photon yield between 300nm and 406nm (used in most experiments) in excited by 0.85MeV electron is 3.81±0.13 photons per meter at 1013hPa and 20℃. For (2), we have shown the new method to use energy deposition rather than the number of charged particles for each angular bin in the camera of the detector to estimate the primary cosmic rays. Parameters in each wavelength have been given for application to estimate the energy deposition.
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