Investigation of Proton Beam-Driven Fusion Reactions Generated by an Ultra-Short Petawatt-Scale Laser Pulse

Table 3

Reaction product yields per primary projectile in BN and expected yields for the BN nanotube 1ω spectrum.

Reaction product	3α	^11C	^13N		^18F
Reaction	^11B (p, α)2α	^11B (p, n)^11C	^10B (α, n)^13N	^16O (p,α)^13N	^14N (α, γ)^18F	^18O (p, n)^18
Q value (MeV)	8.59	−2.76	1.06	-5.22	4.415	−2.44
Threshold energy (MeV)	0	3.017	0	5.547	0	2.575
Target ion density (cm^−3)	2 × 10^22	2 × 10^22	5 × 10^21	1.5 × 10^21	2.5 × 10^22	3 × 10^18
Expected N2 per J	6 × 10^6	66,000	0.5	800	1	80
Measured N2 per J (Table 2)	n/a	37,000	1300	1300	75	75

The ion densities are calculated assuming the BN plate (density of 2.1 g/cm³) contains ∼95% BN and ∼5% oxygen contamination. The natural boron consists of 80%¹¹B and 20%¹⁰B. Of the natural oxygen, the ¹⁸O isotope is about 0.2% abundant. N₂ is given per shot per J of laser energy.