Neutron-Induced X-Ray Fluorescence (NIXRF)
Definition
A synchrotron-based method using neutrons to probe deep obliterations; can detect digit geometry buried several millimetres beneath a machined surface, entirely non-destructively.
- Method
- Synchrotron-based
- Probes
- Neutrons interacting with obliterated markings
- Depth
- Several millimetres beneath a machined surface
- Advantage
- Entirely non-destructive
Common questions
Why is non-destructive detection of erased serial numbers valuable?+
It preserves the original evidence and chain of custody, avoiding the etching or polishing steps that conventional restoration methods use and that can themselves alter the surface.
Why is NIXRF rare in routine forensic laboratories?+
It requires access to a synchrotron facility, which is far less accessible and far more costly than conventional chemical or electrochemical serial-number restoration methods.
Related terms
- ASTM E2885-13
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- Davis Reagent
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- Electrolytic Etching
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- Fry's Reagent
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- INTERPOL iARMS
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- Magnetic Particle Inspection (MPI)
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- Profilometry
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- Turner's Reagent
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- Ultrasonic Cavitation
- High-frequency pressure waves that collapse cavitation bubbles preferentially at high-energy surface zones; an alternative physical restoration method for stainless-steel and titanium substrates.