Yields on the formation of OH groups and the loss of CH groups along nuclear tracks in PADC films

Sudden Increase of the Radiation Chemical Yield for Loss of Carbonate Ester in PADC Detector where the Track Overlapping of 28 MeV Electrons Becomes Significant

“…The results were concordant to that of loss of ether within the experimental error [3]. We applied this model to the present case, regarding the fluence of 1.6×10 15 electrons/cm 2 as the critical fluence where the overlapping becomes significant, the value of 0.04 nm was derived, which is in the same order to those of considered functional groups here. In the other study about the effects on PADC films of UV lights with a wavelength of 222 nm, similar fluence-dependence was observed, in which the carbonate ester decreased only above 3.0×10…”

“…The relative absorbance of ether decreases linearly with increasing the fluence, similar to that in the cases of gamma ray, protons and heavy ions [2,3,4]. On the other hand, that of carbonate ester decrease above a certain fluence of 1.6×10 15 electrons/cm 2 . Around the same fluence, the increasing rate of OH groups begun to decrease.…”

“…It was also reported that the amount of OH groups is comparable to the damage density of ether for protons and heavy ions [15]. Unfortunately, we could not determine the amount of OH groups along 28 MeV electron tracks, because the beam intensity was not uniform within the spot size of IR measurement.…”

“…One possible interpretation is that the sudden decreases of carbonate ester should relate to overlapping of electron tracks. We may call the fluence region below 1.6×10 15 electrons/cm 2 as the single-hit zone and that of higher fluence as the multi-hits zone. The trend of CH groups is slightly different from that of carbonate ester.…”

“…Since the relative absorbance of carbonate ester and CH groups decreases only above the fluence of 1.6×10 15 electrons/cm 2 , as indicated in Fig. 3, one cannot simply apply Eq.…”