The emission of nuclear particles (protons, deuterons, neutrons and alpha particles) was detected during the irradiation of different targets, including 30μm thick Ti metal and TiD foils, as well as CH2-film, by an intense picosecond laser beam (I = 2.0× 1018 W/cm2, λ = 1.053 μm). The nominally pure Ti metal target contained some adsorbed hydrogen (TiHx). It was shown, that the main component of emitted particles is consisted of protons/deuterons (Np ∼1011 sr−1 per pulse) accelerated up to the energyEp ≤ 0.8MeV. Energetic 3MeV protons and neutrons (∼104 per pulse into 4π sr.) were detected in the case of TiDx experiments, and both can be considered as a signature of the dd-fusion in the target. The emission of α-particles (Eα ≥ 10MeV, Nα ∼ 104 sr−1 per pulse), never previously observed in experiments with solid (nonmetal-hydride) targets, was detected in the case of TiHx and TiDx foils. The emission of ions with mass A > 4 (Ni ∼104 to 105 sr−1 per pulse) has also been detected on TiD/H targets. The energy of these ions, estimated with the shielding filters was found to be Ei ≥ 3.0MeV per nucleon.
7 Figures and Tables
Figure 1. The scheme of experimental setup.
Table 1. Summary of results from laser irradiation experiments.
Figure 2. The calibration dependence of track diameters of alpha-particles and protons on their energy, ( ): radioactive alpha-sources; (•): particle beams.
Figure 3. The photomicrographs of detectors, exposed without the filter behind the target, R = 4 cm, ϕ = 180◦, (a) TiDxtarget and (b) TiHx target.
Figure 4. The track diameter distributions for the detectors showed in Fig. 3, Sdet = 1.4 × 10−3 cm2, (a) TiDx target and (b) TiHx target.
Figure 5. The track diameter distributions for the detectors exposed with the 25µm Cu filter behind the target, R = 4 cm, ϕ = 180◦, Sdet = 0.8 cm2, (a) TiDxtarget and (b) TiHx target.
Figure 6. The α-particle energy distributions, (a) TiHx target and (b) TiDxtarget.
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