Calibration of CR-39 with atomic force microscope for the measurement of short range tracks from proton-induced target fragmentation reactions

On the use of CR-39 PNTD with AFM analysis in measuring proton-induced target fragmentation particles

“…The REL value of a particle is obtained from the measured S value by using an empirical relation or calibration curve between S and REL [8,9,15]. For the CR-39 PNTD, a deltaray cut-off energy of 200 eV has been empirically determined [9].…”

“…The REL value of a particle is obtained from the measured S value by using an empirical relation or calibration curve between S and REL [8,9,15]. For the CR-39 PNTD, a deltaray cut-off energy of 200 eV has been empirically determined [9]. The REL value in CR-39 [MeV cm 2 /g] can be converted into LET in water (LET) [keV/lm] by using a conversion factor of LET/REL [16,17].…”

“…In other words, CR-39 PNTD responds only to secondary high LET particles. CR-39 PNTD provides an accurate LET spectrum [8] and is sensitive to particles with LET up to 2.0 MeV/lm [9]. When CR-39 PNTD is used in the plateau region of the Bragg curve of proton radiotherapy beams, this detector has a sensitivity only for proton-induced target fragments and can therefore be used to evaluate their dose contribution.…”

“…The absorbed dose and dose equivalent measured by CR-39 PNTD and analyzed by an optical microscope will then underestimate the contribution from short range target fragments [10]. This limitation can be overcome by analyzing CR-39 PNTD with an atomic force microscope (AFM), following a chemical etch of <1 lm [9,11]. This technique permits accurate measurement of tracks from charged particles with range >1 lm.…”

Digital holographic microscopy for recording and analysis of 3D images of etched tracks in LR-115 SSNTD

“…The 3D visualization of etched tracks will reveal its morphological and geometrical parameters, which contribute to the applicability of this detector in alpha spectrometry. Since DHM can provide 3D topographical maps of the scanned post-etch surface of the detector, in principle the evolution of the etched track profiles may be directly determined, at least until the etching solution reaches the polyester layer and not only during the initial etching process as it happens with AFM [16]. According to simulation results, shallow tracks and thus short etching time are needed to be able to study the full track profile with AFM [17].…”