Beam characterization of a lab bench cold cathode ultra-soft X-ray generator

Abstract

International audienceThe aim of this work is to characterize the Ultra Soft X-ray (USX, 1.5 keV, Al Kα) photon beam of a customized lab bench cold cathode generator. Within this generator, the electron beam is slowed down in a thin aluminium foil (16 μm) supported by an easily exchangeable anode. It is shown that the thickness of the foil and the anode configuration determine the spatial distribution and the fluence rate of the photon beam, whereas accelerating voltage determines both fluence rate and energy spectrum feature. It is shown also that under specific operation parameters (i.e. accelerating voltage), a Gaussian energy distribution of the beam can be generated which is centred on the energy of the Al Kα line (1.5 keV). Dosimetric films of GAFCHROMIC® HD-810 were used to estimate the photon fluence rate distribution of the beam. Its variation, when the generator acts as a monoenergetic source, was characterized with the two different configurations of the anode assembly. Finally, it is verified that the anode assembly consisting in a flat washer, on which the aluminium foil is set, acts as a simple point-source

Evidence for a critical dose above which damage to carbonate ester bonds in PADC appear after gamma ray and ultra soft X-ray exposures

“…Gamma ray exposures were carried out in ambient air at 77 K (using liquid nitrogen) and RT using the intense Co-60 source "Rabbit 11", an equipment of The in the present study. The beam profile was guaranteed to be uniform on at least a diameter of 3 mm (Ounoughi et al, 2013). The mean absorbed dose rate in PADC films was 1.0 Gy/s.…”

Complexation des acides aminés basiques arginine, histidine et lysine avec l’ADN plasmidique en solution aqueuse : participation à la capture de radicaux sous irradiation X à 1,5 keV

“…Les solutions complexes sont exposées en environnement atmosphérique à la raie Kα de l'aluminium à l'aide d'un générateur de rayons X à cathode froide dont le faisceau a été caracté-risé finement [9,10,11]. Le dispositif complet est schématisé en figure Ultra-Soft X-ray irradiation device.…”

Spatial distribution of air kerma rate and impact of accelerating voltage on the quality of an ultra soft X-ray beam generated by a cold cathode tube in air

“…For electrons accelerated at energies up to 5 keV, the maximum range in aluminum is about 0.5 mm (Ounoughi et al, 2013) and Xrays generated at this depth cross the remaining thickness (15.5 microns which thus additionally plays the role of a USX filter) and then are emitted in the air in the direction of the sample (placed at 10 mm from Al foil in this work). The photon transmission of a 15.5 mm thick Al foil and 10 mm of air thickness allows the energy spectrum to be predicted.…”

“…In a research laboratory, a simple method to producing continuous USX beams on a lab-bench is to use a transmission Cold Cathode X-ray tube which provides excellent spectral purity (~99%), i.e. the bremsstrahlung component can be lowered near to zero (Hill, 2003;Ounoughi et al, 2013). It is well-known that the tube voltage modifies the energy spectrum and the intensity of a Xray beam.…”