Expert Groups and Facility Stakeholders
NIF has a number of expert groups and facility stakeholders that are consulted throughout the shot preparation and execution process. Stakeholders formally review experiments in advance of the setup review. Formal approval by any stakeholder is captured and documented online with the Approval Manager tool. For issues related to experiment execution that arise in real time and cannot be resolved within a specific review, a management review board (MRB) is convened.
The alignment group provides the technical expertise to support the fabrication and metrology of a target or diagnostic for alignment. The group provides tools, procedures, and processes to support the development of the alignment plan and reviews all supporting documentation. Alignment group members typically need to work with the Target and Laser Interaction Sphere (TaLIS) as the alignment plan is being drafted.
Beamline and Laser Integrated Performance (BLIP)
BLIP is responsible for reviewing the experiment in the context of laser performance and safety. BLIP maintains the Laser Performance Operations Model (LPOM) that predicts and optimizes system performance for each experiment’s requested laser pulse. The BLIP team is also available as a resource to help define the laser requirements and evaluate whether expected performance will meet the shot goals. This group coordinates with the NIF Optics Loop (NOL) as needed.
Targets and experiments are assessed to ensure that no classified data can be acquired without proper controls and procedures in place.
Cleanliness and Materials
NIF Operational Cleanliness personnel conduct evaluations of materials and cleaning that are required as part of the materials review and approval process and also provide oversight of cleanrooms, cleaning vendors, and facilities in which clean assembly of equipment is performed to ensure compliance with NIF cleanliness protocols. The chairman of the Cleanliness Steering Committee must authorize any new equipment before it can be installed on NIF.
Representative stakeholders from the Diagnostics organization provide various types of review throughout the experimental process. New diagnostic instruments and DIM-based snouts are long-lead items (greater than six months) that are passed through a series of design reviews before construction begins. Reviewers are assessing all aspects associated with the instrument, including safety, size, weight, compatibility specifications, and system requirements. Diagnostics members are also available to offer guidance and review of requests for small hardware modifications (no later than three months from shot date). Guidance on the use of existing diagnostics (e.g., availability of common consumable parts) in a given experiment is also provided.
NIF Optics Loop (NOL)
NOL provides expert assessment of NIF campaign cost and feasibility with regards to final optics use and the required capacity for supporting optics loop infrastructure. The group generates the final optics exchange plan, inspection plan, and blocker plan for review during the shot approval process. In addition, NOL supports the decision-making required for day-to-day operation of the NIF optics loop.
The Radiological Operations group provides guidance and resolution on Environment, Safety & Health issues related to radiological safety. The working group assists in the characterization and understanding of hazards and advises whether the issue falls within safety and environmental limitations. The group recommends controls
or alternative approaches in order to reach a consensus consistent with NIF policy.
Target and Laser Interaction Sphere (TaLIS)
The TaLIS working group considers all issues relevant to the target chamber and target area. TaLIS provides expert group review, evaluation, and recommendations on issues in the NIF target chamber, including experimental campaign planning and shot setup reviews and online commissioning activities, including:
• Experimental configuration of diagnostics, targets, and beams (including chamber interferences).
• Target, diagnostic, and beam alignment and readiness.
• Laser–plasma interaction and backscatter source estimation.
• Unconverted light interaction with targets, diagnostics, chamber, and laser.
• Target debris and shrapnel effects on target, diagnostics, chamber, and debris shields.
The group also reviews processes for safe and effective operations in the NIF target chamber and participates in target area design reviews. The TaLIS model-based expert analysis is a critical aspect of shot planning.
The Target Operations group installs the target and supports gas and cryogenic operations as required for experiments. This group provides guidance and develops procedures and processes to support requested target setups.
The target engineering organization follows a design review process for all targets built at LLNL/General Atomics. A target engineer works with the appropriate stakeholders to uncover any physics, safety, and cleanliness issues. In particular, TaLIS is consulted early in the process to verify that there are no concerns pertaining to debris and shrapnel and configuration. Targets supplied by the experimentalist are also evaluated to ensure that they meet certain fundamental design and materials requirements. See Chapter 7 for more information.