Beam based alignment and its relevance in Indus-2

Area of Science:

• Particle Accelerator Physics
• Beam Dynamics
• Control Systems Engineering

Background:

• High corrector magnet strength was required for closed orbit distortion (COD) correction in the Indus-2 storage ring.
• Beam position monitor (BPM) readout offsets were found to limit the achievable COD correction.
• Accurate COD correction is crucial for efficient particle accelerator operation.

Purpose of the Study:

• To investigate the impact of BPM offsets on COD correction.
• To implement a beam-based alignment (BBA) method to estimate and correct BPM offsets.
• To minimize COD in the Indus-2 storage ring through improved alignment and control.

Main Methods:

• Beam-based alignment (BBA) was employed to determine the electrical center offsets of BPMs relative to quadrupole magnetic centers.
• An active shunt power supply (ASPS) system was designed and implemented for individual quadrupole magnet control.
• COD was measured before and after the BBA procedure and ASPS implementation.

Main Results:

• Initial COD correction achieved 1.3 mm rms (horizontal) and 0.43 mm rms (vertical).
• After BBA and ASPS implementation, COD was significantly reduced to 0.45 mm rms (horizontal) and 0.2 mm rms (vertical).
• The ASPS system demonstrated efficient control for individual quadrupole magnets.

Conclusions:

• BPM offsets are a significant factor affecting COD correction accuracy in particle accelerators.
• The BBA method effectively estimates and compensates for BPM offsets.
• The developed ASPS and BBA methodology successfully minimized COD, enhancing accelerator performance.