What is the monthly phase/amplitude beam control tolerance?

• A. 1%
• B. 2%
• C. Functional
• D. ±1 mm

Answer: (C)

The monthly phase and amplitude beam control tolerance is a functional tolerance. This means the requirement isn’t a fixed numeric limit like a percentage or a millimeter value; instead, it is defined by whether the beam control maintains the system’s operational performance. On a monthly basis, the focus is on ensuring phase stability and amplitude stability are sufficient to deliver the beam with the required quality for users and experiments. If the control system can achieve the needed functional performance under typical operating conditions, that satisfies the tolerance. Rigid numeric bounds would not capture how real-world beam delivery depends on how well the system functions as a whole, so the functional category is the appropriate designation.