Remote detection of radioactive material using mid-IR laser–driven electron avalanche

Abstract

Remote detection of a distant, shielded sample of radioactive material is an important goal, but it is made difficult by the finite spatial range of the decay products. Here, we present a proof-of-principle demonstration of a remote detection scheme using mid-infrared (mid-IR) (λ = 3.9 μm) laser–induced avalanche breakdown of air. In the scheme’s most basic version, we observe on-off breakdown sensitivity to the presence of an external radioactive source. In another realization of the technique, we correlate the shift of the temporal onset of avalanche to the degree of seed ionization from the source. We present scaling of the interaction with laser intensity, verify observed trends with numerical simulations, and discuss the use of mid-IR laser–driven electron avalanche breakdown to detect radioactive material at range.

Radiological Survey of Oil and Gas Wastes and its Health Risks in Niger Delta Region of Nigeria

“…Drill cutting (A) and pipe scales (B) were sampled dry, pulverized and homogenized by grinding it into powdery form. The powdered sample was then sieved using a 2 mm sized mesh screen to obtain a fine texture of the samples [14]. The pulverized samples were then oven dried at 110C until they attained constant weight.…”

“…In order to manage personal radiation exposures, NORM management plan ought to be established in oil and gas industries. This plan is to ensure that personal radiation exposures are maintained not only below the relevant annual radiation exposure limit but as low as reasonably achievable (ALARA) [8].…”

“…International Association of Oil and Gas Producers (IOGP) [14,15] explains the various routes through which radioactive pollution occur during oil and gas production.…”

Absolute Measurement of Laser Ionization Yield in Atmospheric Pressure Range Gases over 14 Decades

“…The peak probe intensity defines a breakdown volume inside of which the intensity exceeds a threshold value leading to detectable avalanches (see supplementary material [21]). Crucially, the mid-IR avalanche driver eliminates driver-supplied MPI electrons from the seed population [22,23].…”

“…μm, 85±5 fs) and focused to peak intensities of 1-100 TW/cm 2 , with intensity control provided by a waveplate and polarizer. All three pulses were derived from a 20 Hz chirped pulse amplification (OPCPA) system [24], with details of focal spot measurements, breakdown volume, and absolute intensity uncertainty (~± 10% ) given in the supplementary material [22]. As the yield (and seed electron density) increases even further, ≲10 −10 to 10 −2 , adjacent incipient avalanche sites become closer than the electron diffusion length and it is no longer possible to resolve and count breakdowns.…”