An analytical study of double bend achromat lattice

Area of Science:

• Accelerator Physics
• Synchrotron Radiation Technology

Background:

• The Chasman-Green (CG) lattice is a fundamental structure for low emittance synchrotron radiation sources.
• The basic CG lattice utilizes a single focusing quadrupole (QF) magnet to achieve achromatism.

Purpose of the Study:

• To analyze the limitations of the basic CG lattice in achieving theoretical minimum beam emittance under achromatic conditions.
• To present and study advanced achromat designs with two, three, and four quadrupole structures for improved emittance.
• To investigate the effectiveness of different quadrupole arrangements (QF and QD) in these advanced structures.

Main Methods:

• Analytical approach using thin lens approximation for quadrupoles.
• Examination of basic CG lattice limitations.
• Development and analysis of multi-quadrupole achromat structures.
• Case study of the Indus-2 lattice with a QF-QD-QF configuration.

Main Results:

• The basic CG lattice demonstrates limitations in achieving theoretical minimum beam emittance while maintaining achromaticity.
• Multi-quadrupole achromat structures (two, three, and four quadrupoles) are presented as solutions.
• Different arrangements of focusing (QF) and defocusing (QD) quadrupoles are analyzed within these advanced structures.
• The QF-QD-QF configuration in the achromat section of the Indus-2 lattice is studied.

Conclusions:

• The basic CG lattice is insufficient for achieving optimal beam emittance.
• Advanced achromat designs with multiple quadrupoles are necessary to meet theoretical minimum emittance requirements.
• The study provides analytical insights into lattice design for enhanced synchrotron radiation source performance.