[19p-W810-1~16] 2.2 Detection systems

△ [19p-W810-12] Analysis of electron tracks in PADC detector

〇(D)Tamon Kusumoto¹, Yutaka Mori², Masato Kanasaki¹, Keiji Oda¹, Yoshihide Honda³, Sachiko Tojo³, Tomoya Yamauchi¹ (1.Kobe Univ., 2.CSREA, 3.ISIR)

Keywords:PADC,Electron beam,CR-39

In order to under stand the modified structure along the latent tracks in poly(allyl diglycol carbonate), PADC, a series of FT-IR spectrometric studies have been performed. We have examined the effects of the exposures to protons and heavy ions between He and Xe, covering the stopping powers ranging from 1 to 12,000 keV/μm, as well as gamma rays from Co-60 source with an average LET of about 0.4 keV/μm. Since the PADC is the most sensitive etched track detector, such information will be valid to find the relation between the modified structure and track registration property, which should be helpful to find some suitable molecular arrangements with higher detection sensitivity. In the present study, we conducted the FT-IR studies on PADC films exposed to 28 MeV electron beams, of which LET, liner energy transfer, are about 0.025 keV/μm, utilizing the L-band LINAC at The Institute of Scientific and Industrial Research, Osaka University, Japan. The relative absorbance, the ratio of the absorbance before and after the exposure, of ether bond decreased monotonically with increasing the abosorbed dose. However, in the case of C=O bond, the relative absorbance started decreasing from 48 kGy of absorbed dose. These experimental results indicate the loss of C=O bond occured only after the ether bond was damaged. The radiation chemical yields for loss of ether bond for 28 MeV electron beam in PADC was 17 per 100 eV. And that for the loss of C=O bond for 28 MeV electron beam in PADC was 35. Judging from the higher G values for electron beam, the polymeric chains of PADC are destroyed by secondary electrons not only in track core but also in track hallo region.