Budget Amount *help |
¥10,200,000 (Direct Cost: ¥10,200,000)
Fiscal Year 2006: ¥2,500,000 (Direct Cost: ¥2,500,000)
Fiscal Year 2005: ¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 2004: ¥4,500,000 (Direct Cost: ¥4,500,000)
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Research Abstract |
For elucidation of both the origin of Galactic cosmic rays and the mechanism of the particle acceleration, we have observed TeV gamma rays from supernova remnants (SNRs), and obtained following results from their energy spectra and morphologies. 1. Extended emission from SNR RXJ0852.0-4622 was detected, considering results of the radio and the X-ray observations, (1) TeV gamma-ray emission could be explained to be inverse Compton scattering of electrons being accelerated up to tens of TeV, while X-ray could be synchrotron emission by electrons. However, total energy of electrons is less energetic than that of the standard supernova origin. (2) The emission could be originated in protons being accelerated up to tens of TeV. 2. Extended TeV gamma-ray emission from SNR MSH15-52, containing the pulsar wind nebula of PSR B1509-58, was detected, (1) Considering that morphology of the gamma-ray emission is not shell-like, and that total energy of protons which could explain the gamma-ray emission is larger than that of spindown energy of the pulsar, a scenario of proton origin is rejected. (2) Considering spectral energy distribution (SED) from radio to TeV gamma-ray bands, emission from radio to X-ray bands could be synchrotron by electrons, while gamma-ray emission could be inverse Compton scattering of electrons being accelerated up to hundreds of TeV. The total energy of electrons is from several to tens percents of the spindown energy. 3. Extended TeV gamma-ray emission was detected from the unidentified source HESS J1804-216, in the case of an SNR, the SED could be explained by electrons and protons origins. Based on these results, we found that protons and/or electrons are accelerated up to the TeV band in SNRs. In addition, we have developed a readout system for a signal from a photomultiplier-tube detecting Cherenkov light, with a GHz sampling FADC and a low-power compact ASIC.
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