Development of a multi-detector and a systematic imaging system on the AGLAE external beam

Gold from the tomb of Scribe Beri: a comparative analytical approach to the New Kingdom gold grave goods from Riqqa (Egypt)

“…Quantitative processing was carried out by PyMCA [11] under the conditions defined for gold alloys [12]. The necklace and some of the earrings were investigated by lPIXE (particle-induced X-ray emission) at the extracted beam line of the AGLAE accelerator facility (from the C2RMF in Paris) using a 3-MeV proton beam, and with (1) Si(Li) detectors for the NMS jewellery items and (2) the newly implemented detection system for the LM jewellery items, consisting of several SDD detectors with high active surfaces, increasing the total solid angle of detection of the emitted X-rays [13], and a new scanning system for high spatial resolution fast elemental mapping (down to 10 9 10 lm 2 ), which improves the quality of the data acquired in the case of gold jewellery [14]. In both setups, one of the detectors was covered with a selective filter consisting of 75 lm of Cu to search for trace elements at the conditions defined for the analysis of gold alloys [15].…”

PIXE analyses over a long period: The case of Neolithic variscite jewels from Western Europe (5th–3th millennium BC)

“…The size of the scanned variscite area was 0.5x0.5mm. Note that the scanning was obtained exclusively by a mechanic displacement of the sample before 2012 and after, by a combination of vertical magnetic beam deflection and mechanic translation [5]. Overall, the PIXE concentration of major and minor elements obtained on the DR-N pellet varied within 5% from the recommended values.…”

“…During that period, the AGLAE external beam line underwent experimental and spectrum processing improvements and consequently, the measuring conditions has evolve over time [4,5]. Some parameters have been kept constant, such as the proton beam energy (3 MeV) and intensity (about 2 nA to avoid any beam-induced damage), the geometry (low and high energy detectors placed 45° relative to the beam axis), the filters used (a helium flux of 1-2 l/min, permanent magnets to deflect backscattered particles away from the low energy detector, 50-µm thick aluminum absorber for the high energy detector).…”

“…The beads and pendants were directly submitted to the beam without preparation apart from cleaning with alcohol. On the other hand, some experimental parameters have evolved during the period [4,5]. The Si(Li) detectors were replaced subsequently to failures or improvements: the first Si(Li) detectors employed were from Kevex, the crystals of which were later replaced by ones from Gresham.…”

“…If in the final campaign the strengite molecule is discarded (1.83% of Fe 2 O 3 ), the P/Al ratio closely approaches the value for pure variscite (P/Al=1.148). Note that this run was the first performed using SDD detectors (no dead layer) and GUPIXWIN with parameters adjusted in accordingly [5]. As for the trace element concentrations, the variations are less pronounced than for major elements, as is shown in figure 5 which depicts the evolution of Cr, V, Fe and Ga in the MeH40 variscite bead for over 9 years.…”