@article{oai:yamanashi.repo.nii.ac.jp:00000867,
 author = {小玉, 正弘 and 小倉, 紘一},
 journal = {山梨医科大学紀要, Bulletin of Yamanashi Medical University},
 month = {},
 note = {Diffusion characteristics of auroral X-rays in the atmosphere have been investigated by means of a Monte Carlo simulation to estimate how much degree of out-of-focus is introduced into auroral X-ray images at balloon altitudes. The simulation calculations were carried out for the four different spectral functions of photon sources: a) mono-energy parallel beam, b) mono-energy, isotropic, c) exponential and d) power-law energy spectra, isotropic. The calculation results are summarized as follows. 1) In case of the omni-directinal detector, an isotropically incident beam enlarges into the width of 10-13 km at l0g/c㎡ depth, regardless of the spectral function. 2) The detectors with a half collimator angle of 30and l0reduce it into 8-9 km and 3-4 km, respectively. 3) It appears a kind of ghost image with increasing inclined angle of the collimated detector, amounting to the same order of brightness with the genuine image. The out-of-foci of some circular source images are illustrated as a function of atmospheric depth, spectral function and collimation and inclined angles of the detector.},
 pages = {62--73},
 title = {気球高度で観測されるオーロラX線像の焦点ボケ},
 volume = {4},
 year = {1987}
}