Differential scattering cross sections for elements with 13 ⩽Z⩽ 50 using 59.54 keV gamma rays

Abstract

Coherent and incoherent scattering cross sections have been measured using a high purity germanium detector on elements in the range of Z = 13–50 using 241Am gamma rays. The cross sections have been derived by comparing the net count rate obtained from the Compton peak of aluminum with the elastic/Compton peak of the target element. The measured cross sections for the coherent and incoherent processes are in agreement with the theoretical values.

Effect of synchrotron polarization on grazing incidence X-ray fluorescence analysis

“…The anisotropic nature of the scattered radiation imposes a constraint to place an X-ray spectroscopy detector in a condition where the contribution of the scattered background is minimal. The computation results obtained using the reported literature [14][15][16][17] closely corroborate with the experimental TXRF measurements performed on the standard reference materials and for a few TXRF methodological samples. It is realized that the horizontal detection geometry provides approximately one order of magnitude better signal to background ratio, in contrast to the conventional vertical detection geometry, thus improving TXRF detection sensitivities to $20-60% for most of the elements.…”

“…The gross areas of the Compton and elastic scattered peaks were measured in the vertical and horizontal detection geometries. The polarization factor then calculated following the eqn (10) and values are tabulated in table-2. We have observed degree of polarization ~ 88 2 % for the synchrotron x-ray beam for the TXRF excitation at the Bl-16 beamline.…”

“…From the above equations one can find the total Compton and elastic scattering cross section for an element 10 . The geometrical distribution of the scattered photons can be obtained by calculating the scattering probability density function described by…”

“…To estimate the Compton and elastic scattering density proles we need to substitute the differential scattering cross-sections 16,17 in eqn (1). This allows us to arrive at a relation…”

Small angle scattering of 59.54 keV photons by elemental samples in the atomic number region 13 ≤ Z ≤ 82

“…However, on the experimental side, although a number of methods (B€ oke, 2011;Baek, Bug, Rabus, Gargioni & Grosswendt, 2012Bradley, Goncalves & Kane, 1999;Donativi, Quarta, Cesareo & Castellano, 2007;Kane, 2005;Latha, Abdullah, Unnikrishnan, Varier & Babu, 2012;Poletti, Goncalves & Mazzaro, 2002;Rao, 1991;Shahi et al, 1997;Sharma, Singh, Singh & Sandhu, 2009;Simsek & Ertugrul, 2004;Singh, Sharma, Singh & Sandhu, 2012) have been used to determine the Coherent scattering cross sections, the experimental investigations are relatively scarce particularly for elements at low momentum transfer, for scattering angles below 10 . This may be attributed to the fact that, since the scattering of gamma rays in this region involves low momentum transfer to the struck electron, it is difficult to separate out the coherent scattering from the main peak particularly due to the severe limitations imposed by the finite resolution of the detector (This is the case even with high resolution detectors such as HPGe detector).…”