7.4 Target Diagnostics Infrastructure and Data Acquisition

As discussed in Section 7.1, NIF DLI users are responsible for providing their own test objects and associated diagnostics. There is a camera that has a view of the face of the target that can be used if desired by the user; otherwise there are no target diagnostics provided by the facility. Figure 15 shows the target vessel area and swing panel for connections to local or classified data acquisition (future capability), the target viewing camera port, and location of a spare flange for custom user connections. Cable feedthroughs are provided for target vessel internal cables and have connections on the rear/door side of the target vessel (Figure 16). In addition, there is a 12” port to which users can mount their own flange with vacuum feedthroughs and internal cables. The front facing port (see Figure 13), can be used for custom feedthrough plates. Each port is 12” in diameter but the working area is 8” in diameter.

Target Vessel area showing swing panel for connections to local or classified data acquisition (future capability), target viewing camera port, and location of spare flanges for custom user connections.
Figure 15, Target Vessel area showing swing panel for connections to local or classified data acquisition (future capability), target viewing camera port, and location of spare flanges for custom user connections.

Signal cables are to be run inside the test area from the target to a swing box mounted on the test vessel. User signal cables are then to run from the swing box to the user diagnostic equipment. The swing box will eventually provide the same signals to the classified racks in the classified control room. The connections (see Figure 16) that are currently available on the Target Chamber patch panel are:

  • 24 fiber optic, SMF-28e
  • 12 N-type Coax
  • 16 BNC Twinax
  • 2 Multi-connector (16-pin)
Image of available connections on the DLI target vessel
Figure 16. Available connections on the DLI target vessel

The MRE team has a mobile data acquisition system (DAS) that is available for use on DLI experiments. The DAS is housed in a mobile enclosure that is staged next to the DLI target vessel during an experiment and then removed following the shot. The mobile enclosure, shown in Figure 17, is 41 in. x 61 in. x 58 in. (L x W x H) and contains 44U of internal rack space. The standard configuration of the mobile enclosure consists of a 24-channel Photonic Doppler Velocimetry (PDV) system that includes three 8-channel, 2.5 GHz oscilloscopes. The mobile enclosure also includes a heat exchanger for up to 3 kW of heat removal since equipment cannot exhaust more than 50 W into the NIF Target Bay. As the DLI platform progresses, the diagnostic equipment available for use is anticipated to grow. Once users begin to plan and propose a NIF DLI experiment, they are encouraged to reach out to the MRE Lead Engineer or DLI Experimental Lead to discuss their diagnostic needs. These early conversations will enable users to identify whether the available diagnostic equipment will be sufficient and/or begin the planning process for incorporating additional user-supplied equipment or systems.

Mobile enclosure used for data acquisition on DLI experiments. (Left) External view of the enclosure (Right) Internal view of the enclosure outfitted with 24-channel PDV system.
Figure 17. Mobile enclosure used for data acquisition on DLI experiments. (Left) External view of the enclosure (Right) Internal view of the enclosure outfitted with 24-channel PDV system.

All diagnostic systems that are proposed for use by users must be reviewed by the facility. Any diagnostic or support system that introduces a potential hazard into the target vessel or Target Bay must go through appropriate facility design review and approval. As this process can be lengthy, users are cautioned to start this process early (>12 months from scheduled shot dates) to avoid potential delays.