Asymmetric bimodal accelerator cavity for raising rf breakdown thresholds

Area of Science:

• Physics
• Engineering
• Particle Accelerators

Background:

• Standard accelerator structures utilize single-mode cavities.
• Optimizing accelerating gradients while managing high-frequency electric fields and breakdown is crucial for accelerator performance.

Purpose of the Study:

• To investigate an axisymmetric microwave cavity with specific modal properties for accelerator structures.
• To evaluate the potential for increased accelerating gradients and manage electric field amplitudes.

Main Methods:

• Consideration of an axisymmetric microwave cavity with a specific eigenfrequency relationship (second lowest TM-like mode frequency is twice the lowest).
• Analysis of field asymmetry along the cavity axis.
• Computational evaluation of electric field peak amplitudes and accelerating gradients.

Main Results:

• The designed cavity exhibits asymmetric fields along its axis.
• Peak electric field amplitudes pointing into longitudinal faces can be less than those pointing out.
• A structure using these cavities may achieve an accelerating gradient approximately 47% greater than single-mode cavities.
• This enhancement is achievable without increasing the probability of electrical breakdown.

Conclusions:

• The proposed microwave cavity design offers a significant improvement in accelerating gradient.
• This design presents a promising approach for enhancing particle accelerator performance.
• The cavity's field characteristics allow for higher gradients without compromising breakdown limits.