# Optimized quasisymmetric stellarators are consistent with the Garren-Boozer construction

## TL;DR

This paper demonstrates that the core shape and rotational transform of optimized quasisymmetric stellarators can be accurately described by the Garren-Boozer near-axis construction, validating its use as an analytical model.

## Contribution

The study shows that the Garren-Boozer near-axis construction effectively describes optimized stellarator configurations, bridging numerical optimization and analytical modeling.

## Key findings

- Core shape and rotational transform match the Garren-Boozer model
- Supports the near-axis construction as an accurate analytical tool
- Validates the consistency between optimization and analytical approaches

## Abstract

Most quasisymmetric stellarators to date have been designed by numerically optimizing the plasma boundary shape to minimize symmetry-breaking Fourier modes of the magnetic field strength $B$. At high aspect ratio, a faster approach is to directly construct the plasma shape from the equations of quasisymmetry near the magnetic axis derived by Garren and Boozer [Phys Fluids B 3, 2805 (1991)]. Here we show that the core shape and rotational transform of many optimization-based configurations can be accurately described by this direct-construction approach. This consistency supports use of the near-axis construction as an accurate analytical model for modern stellarator configurations.