Unità Funzionale di Fisica Sanitaria Head of the Radio-Protection group Dr. Adolfo Esposit building 15 tel. +39 06 94032621

X-ray Fluorescence Spectroscopy (XRF) at LNF e-mail: astrik.gorghinian@lnf.infn.it

DETECTION TYPOLOGY
NON DESTRUCTIVE: during the diagnosis the sample is not alterated at all

CHARACTERISTIC
sample's chemical elements (detection limits: Z > 13 ; concentrations > 30 ppm) present in an area equivalent to the incident beam spot size, within a thin layer (metals: a fraction of few mm - wood: few cm) are immediately identified in few hundreds of seconds.
Qualitative, semi-quantitative and quantitative analysis can be performed.

SAMPLE TYPE ANALYSED
Liquids, Powders, Solids, Films

APPLICATIONS
archaeology, cultural heritage (Paintings, Metallic crafts, Ceramic, Enamels), geology, industry, environment, ....

Unisantis XMF 104 X-ray Micro Analyser

Instrumentation: X-ray Tube Sample size: the sample holding chamber measures: W.122, H.78, D.116 mm Analogic Signal Amplifier Multichannel Analyser MCA (analogic/digital converter) Acquisition device and data elaborator Semiconductor detector Si(Pin) Peltier cooled

Main characteristic: the spectrometer is equipped with Kumakhov's polycapillary lenses (principle of multiple total reflections) Advantages: focuses spot beam size up to 100 micron acts as a low-band filter due to its own transmission bandwidth improving the minimum detection limit and space resolution obtains high intensity X-ray micro-beam with small divergence angle

Focusing of X-ray beam by capillary system

XRF measurement geometry (in reflection)

Process dynamics: A primary X-ray beam strikes the sample Part of its energy is transferred to the atom's inner shells electrons (photoelectric effect) that leave the atom One or more electronic transitions are induced in the excited atom giving off elemental's characteristic X-ray The spectrum acquires a series of emission lines of intensity related to the concentration of the chemical element present in the sample