International Journal of Energy Science (IJES) Volume 4 Issue 3, June 2014 www.ijesci.org doi: 10.14355/ijes.2014.0403.05 101 Production of 14 MeV Neutrons Using Pyroelectric Crystals: Reconverting Solar Energy into Nuclear Fusion Energy Werner Tornow Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC, USA tornow@tunl.duke.edu Received 19 March 2014; Accepted 27 March 2014; Published 25 April 2014 © 2014 Science and Engineering Publishing Company Abstract By changing the temperature of a LiTaO3 pyroelectric double‐crystal arrangement in a deuterium gas environment, deuterium ions were produced and accelerated towards a tritiated target, producing 14 MeV neutrons via the 3 H(d,n) 4 He nuclear fusion reaction. Keywords Nuclear Fusion; Fusion Reactions in the Sun; Neutron Production; Pyroelectric Crystals Introduction In continuation of our previous work which has focused on initiating the 2 H(d,n) 3 He nuclear fusion reaction with a pyroelectric double‐crystal arrangement (Tornow et al, 2010), we turned our attention to the 3 H(d,n) 4 He nuclear fusion reaction with the goal of producing 14 MeV neutrons. At a first glance this task seems easier than that involving the 2 H(d,n) 3 He reaction with its relatively small Q‐value of +3.27 MeV and its very small reaction cross section of about 16 mb at 100 keV, compared to +17.59 MeV and almost 5000 mb, respectively, for the 3 H(d,n) 4 He reaction. However, the safety requirements associated with the use of tritium, and another tritium‐target related issue, pose severe constraints on operating our standard pyroelectric crystal apparatus in a university environment. Although the 3 H(d,n) 4 He reaction is not very important to our Sun’s energy production, it does take place in the Sun, and it is generally considered as the most practical candidate to reach or even exceed the break‐even point in a controlled fashion on Earth, for example, at the National Ignition Facility (NIF) 1 at Lawrence Livermore National Laboratory, or at the International Thermonuclear Experimental Reactor (ITER) 2 at Cadarache in France. A number of conflicting publications exist about the yield of neutrons produced in another fusion reaction, the 2 H(d,n) 3 He reaction. The work of the RPI group (Geuther, Danon, and Saglime, 2006; Geuther and Danon, 2007; Gillich et al, 2009) provides convincing evidence that neutrons were produced via this reaction. However, doubts exist that the earlier work of the UCLA group (Naranjo, Gimzewski, and Putterman, 2005; Tang et al, 2007) has ever produced the reported number of 2 H(d,n) 3 He neutrons. As has been shown in (Tornow, Shafroth, and Brownridge, 2008), any pulse‐height signals due to 2.5 MeV neutrons obtained with not sufficiently shielded neutron detectors are buried under pile‐up events originating from the intense X‐ray radiation present in pyroelectric crystal experiments. The suspicion appears to be confirmed by the UCLA group’s recent work involving the 3 H(d,n) 4 He reaction (Naranjo, Putterman, and Venhaus, 2011). In Figure 5 of (Naranjo, Putterman, and Venhaus, 2011) the pulse‐ height region identified to be associated with 3 H(d,n) 4 He neutrons appears to be again due to pile‐ up X‐ray events, which are misidentified as neutrons in the pulse‐shape discrimination electronics (Tornow, Shafroth, and Brownridge, 2008). This conclusion seems also to be supported by their yield versus deuteron energy curve (Figure 3 in (Naranjo, Putterman, and Venhaus, 2011)) which does not follow 1 See https://lasers.llnl.gov 2 See https://www.iter.org/proj