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The measurement of Absorption edge parameters of the L III edge of pure elements Hg, Tl, Pb and Bi along with their compounds HgCl2, HgO, HgF2, TlCl, Tl2O3, PbCl2, PbF2, Pb3O4, BiF3, BiCl3 and Bi2O3 has been done using EDXRF technique. In the present measurements 241Am (59.54 keV) radioactive source of activity 100 mCi along with CANBERRA make cryo-cooled Si (Li) detector is used. The measured results are compared with theoretically calculated values from FFAST version 2.1 (Chantler et al., 2005) and shows good agreement with each other within experimental uncertainties within 3.5%. It is observed that the values of absorption edge parameters of the LIII edge depends slightly on the chemical environment and shows almost constant behaviour with effective atomic number ( Z eff )

Total bremsstrahlung (BS) spectra in thick targets of Al, Ti, Sn and Pb produced by beta emitter 90Sr (End point energy=546 keV) are studied in the photon energy range of 1–100 keV. The experimentally measured BS spectra are compared with the theoretical spectral distributions calculated from Elwert corrected (non relativistic) Bethe–Heitler [EBH] theory, modified Elwert factor (relativistic) Bethe–Heitler [Fmod BH] theory for ordinary bremsstrahlung (OB) and the Avdonina and Pratt [Fmod BH+PB] theory, which include the contribution of polarization bremsstrahlung (PB) into OB. The present results are indicating the correctness of Fmod BH+PB theory in the low energy region, where PB dominates into the BS, but at the middle and higher photon energy region of the bremsstrahlung spectrum, the Fmod BH theory is more close to the experimental results. The description of the bremsstrahlung process in stripped atom (SA) approximation, which indicates the suppression of the bremsstrahlung at higher energy ends due to the production of PB in the low energy region, needs further considerations. Hence, the present measurements for BS for different target materials indicates that the considerations of the screening effects along with other secondary effects during the interaction of incident electrons with the target nuclei are important while describing the production of bremsstrahlung, particularly for the higher energy regions.

An experimental measurement has been carried out for measuring the absorption edge parameters i.e. jump ratio and jump factor for elements of lanthanide series “La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb” ( Z =57–70) by using an EDXRF technique. Measured values of such parameters have been compared with theoretical values to check the experimental uncertainties and it was found that experimental results are in good agreement with theoretical values of Chantler et al. (2005, 〈 http://physics.nist.gov/ffast 〉, NIST, Gaithersburg).

We report a study on the carbon ion beam induced modifications on optical, structural and chemical properties of polyallyl diglycol carbonate (PADC) commercially named as CR-39 and Polyethyleneterepthalate (PET) polymer films. These films were then irradiated by 55 MeV C 5+ ion beam at various fluences ranging from 1×10 11 to 1×10 13 ions/cm 2 . The pristine as well as irradiated samples were subjected to UV–Visible spectral study (UV–Vis), Photoluminescence (PL), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. It has been found that ion irradiation may induce a sort of defects in the polymers due to chain scission and cross linking as observed from PL spectral study. It is revealed from UV–Vis spectra absorption edge shifted towards longer wavelength region after irradiation with increasing ion fluence. This shift clearly reflects decrease in optical band gap. The XRD study indicates the gradual decrease in intensity in case of PADC with increasing ion fluence. However, the intensity pattern increased in case of PET at fluence of 10 11 ion/cm 2 then decreased with further increase in fluence. Crystalline size of PADC was found to be decreasing gradually with increase of ion fluence. Whereas, the crystalline size of PET films found to increase with lower fluence and decreases with higher ion fluence. FTIR spectrum also shows the change in intensity of the typical bands after irradiation in the both the polymers. The results so obtained can be used successfully in heavy ions dosimetry using well reported techniques.

LIII subshell absorption edge jump factor and jump ratio of elements W, Au and Hg have been measured experimentally using EDXRF technique using X-PIPS Si (Li) detector. 90° reflection geometry has been used to detect the emitted fluorescent L X-rays from the target elements excited by 59.54 keV gamma-rays emitted from 241Am radioactive point source. Measured values of these parameters have been compared with different theoretically calculated values obtained from XCOM ( Berger et al., 2005 , Chantler et al., 2005 ). Result shows a fairly good agreement within experimental uncertainty. These parameters have been reported for the first time for aforesaid elements using this methodology.

Energy dispersive X-ray fluorescence technique (EDXRF) has been employed for measuring K-shell absorption jump factors and jump ratios in elements Mn, Fe, Co, Cu, Zn, As and Sr using an X-PIPS Si(Li) detector. 90° reflection geometry has been used to detect the emitted fluorescent K X-rays from the target elements excited by 59.54 keV gamma-rays emitted from an 241 Am radioactive point source. Measured values of these parameters have been compared with different theoretically calculated as well as with other available experimental values. It is found that the present results fairly agree with theoretically calculated and experimental values within experimental uncertainties.