# In-Line Target Production for Laser IFE
## 5 Conclusions  
In the direct-drive approach to IFE, the free-standing cryogenic targets of high gain design are required for fueling a laser energy plant. The targets must be delivered to the chamber center with a high accuracy and a high repetition rate. Because fusion reactions must occur approximately ten times per second, the FST-TL becomes an integral part of any fusion reactor. The FST-TL consists of a target production facility, target acceleration, and injection and tracking systems. Currently, target production is in transition from one-of-a-kind to one million of high quality ignition targets per day. Creation of the target delivery system based on noncontact positioning and transport of the cryogenic targets represents one of the major tasks, as well. Therefore, in the frame of IAEA CRP F13016 [1, 27], of particular concern is development of a conceptual design of FST-TL including a mass-manufacturing of reactor-scaled targets and their noncontact delivery at the laser focus. Achieving controlled thermonuclear ignition is one of the goals for IFE, and a target with the isotropic fuel structure is a critical aspect of successfully reaching that goal. This indicates that currently target fabrication technologies for IFE laser experiments are a challenge. A promising candidate is the FST layering method--fast fuel layering inside moving free-standing targets--which is well suited to economical mass production of IFE targets. The cost of the targets produced by the FST layering method may be several orders of magnitude lower than for the traditional target fabrication capabilities and technologies. In this paper, high-gain direct-drive cryogenic targets using foam to support the D\(-\)T fuel were analyzed. These are the shells of \(\sim\)4 mm in diameter with a wall from compact and porous polymers. The layer thickness is \(\sim\)200 \(\upmu\)m for pure solid fuel and \(\sim\)250 \(\upmu\)m for in-foam solid fuel. A credible path to solve the issue is the FST layering method developed at the LPI. This method is unique and has no analogs in the world. The computation showed that the layering time for such targets was \(\tau_{\text{form}}<\) 23 s for D\({}_{2}\) and \(\tau_{\text{form}}<\) 30 s for D\(-\)T fuel, and they can be successfully fabricated by the FST-layering method inside the n-fold LCs at n = 2, 3. So, fast fuel layering is a necessary condition for the producing targets in the massive numbers and for obtaining fuel as isotropic ultrafine layers. Namely, isotropic fuel structure supports the layer quality survivability under the target acceleration, injection, and transport through the reactor chamber. For on-line characterization and tracking of the injected targets it is planned to apply the method of coherent optics based on the Fourier holography. Additionally, throughout this paper, the principle of innovative HTSC-maglev transport systems are explored for the safe, stable and noncontact target delivery at the laser focus. We address this question both by experimentally demonstrating such system performance and by calculating their parameters. The HTSC levitation is based on the interaction between the magnet and the HTSC. Due to unique characteristics, the HTSC materials have demonstrated tremendous potential for the noncontact target transport. Any maglev scheme has to address three basic properties: levitation, guidance, and acceleration. The characteristics of the permanent magnets composing the guideway in the PMG-system are very important in terms of levitation force and stability. We found that not always complicated magnet arrangements bring significant improvements with respect to some simpler arrangements that also provide large levitation force. In our study we use two simple magnet arrangements: linear and circular. In the experiments with one-stage linear accelerator, the HTSC-Sabot from the second generation tapes Gd123 gains a speed up to \(\sim\)1 m/s which remains the same over a 22.5-cm magnetic track (movement time is 0.22 s).