**6. References**

Aglincev, K.K, Ostromuhova, G.P. and Holnova, E.A (1960). Izm. Techn. 12, 40


**2** 

*USA* 

*Western Kentucky University* 

**Material Analysis Using Characteristic** 

Alexander P. Barzilov, Ivan S. Novikov and Phillip C. Womble

Neutron interrogation based methods of non-destructive analysis are well established techniques employed in the field of bulk material analysis. These methods utilize a source of neutrons (a neutron probe) to irradiate objects under scrutiny. Nuclear reactions initiated by neutrons in the volume of the irradiated sample include the following: inelastic neutron scattering, thermal neutron capture, and neutron activation. As a result of nuclear reactions with the material inside the object, the "fingerprint" -rays are emitted with characteristic energies. These characteristic gamma rays are used for the elemental identification. By measuring and counting the number of -rays emitted with a specific energy, one can deduce the amount of the associated chemical element in the sample. The amounts of chemical elements measured allow specifying the chemical composition of the analyzed

Neutron technique is an excellent choice to rapidly determine elemental content of the sample *in situ* in non-intrusive manner. It is a great fit for in situ applications that involve samples that are hard to reach or unsafe to handle, and that require the analysis to be

Accelerator based neutron sources such as deuterium – deuterium (d-d) and deuterium – tritium (d-t) fusion neutron generators provide the electronic control of neutron emission including its time structure. The pulse mode of neutron production allows the use of coincidence methods to segregate prompt and delayed gamma ray signatures emitted from neutron induced nuclear reactions. The kinematics of fusion reactions allows "tagging" of

The pulse neutron systems are used in industry for analysis of coal (Dep et al., 1998; Sowerby, 2009), cement (Womble et al., 2005), metal alloys (James & Fuerst, 2000), in geological and soil analysis (Wielopolski et al., 2008), and oil well logging (Nikitin & Bliven, 2010). Security applications of neutron based systems are for chemical and explosive threats detection (Vourvopoulos & Womble, 2001; Aleksandrov et al., 2005; Lanza, 2006), including the search for threats in cargo containers (Barzilov & Womble, 2003) and vehicles (Reber et al., 2005; Koltick et al., 2007), humanitarian demining and confirmation of unexploded ordinance (Womble et al., 2002; Holslin et al., 2006). Such technologies are considered in astrochemistry applications for in situ analysis of planetary samples (Parsons et al., 2011).

**1. Introduction** 

sample.

performed rapidly, in real time.

outgoing neutrons using the associated particles.

**Gamma Rays Induced by Neutrons** 

