Extended performance gas Cherenkov detector for gamma-ray detection in high-energy density experiments

Area of Science:

• Nuclear Physics
• Plasma Physics
• High-Energy Physics

Background:

• The detection of gamma rays from fusion reactions is crucial for understanding plasma conditions.
• Existing diagnostics have limitations in sensitivity and energy threshold for certain fusion reactions.
• Advanced detector development is needed to probe new regions of the gamma ray spectrum.

Purpose of the Study:

• To develop a new Gas Cherenkov Detector (GCD), named Super GCD, with improved low-energy threshold and high sensitivity.
• To enable the detection of gamma rays in a previously inaccessible portion of the spectrum.
• To enhance the capabilities of diagnostics at the OMEGA Laser Facility and the National Ignition Facility (NIF).

Main Methods:

• The Super GCD is designed for high-pressure operation (≤400 psi absolute) using all-metal seals.
• Fluorinated gases, such as C2F6, are utilized to achieve a low gamma energy threshold of 1.8 MeV.
• The detector's efficiency is compared to existing diagnostics like the Gamma Reaction History diagnostic at NIF (GRH-6m).

Main Results:

• The Super GCD achieves a gamma energy threshold as low as 1.8 MeV with 400 psi of C2F6.
• This new capability opens up a new portion of the gamma ray spectrum for analysis.
• At 20 cm from the target chamber center, Super GCD is approximately 400 times more efficient at detecting 16.7 MeV DT fusion gammas than GRH-6m at its minimum threshold.

Conclusions:

• The Super GCD represents a significant advancement in gamma ray detection for fusion research.
• Its low energy threshold and high sensitivity will provide unprecedented insights into fusion processes.
• This technology will enhance diagnostic capabilities at major fusion facilities like OMEGA and NIF.