Conserved charges of non-yangian type for the Frahm-Polychronakos spin chain

TL;DR

This paper derives a new set of conserved charges for the Frahm-Polychronakos spin chain, revealing a novel type of symmetry that extends the known Yangian structure.

Contribution

It introduces a generating function for conserved charges exhibiting Yangian symmetry that are not expressible in terms of traditional Yangians.

Findings

Conserved charges form an involutive set.

Charges exhibit spin chain Yangian symmetry.

Charges are not expressible in terms of known Yangians.

Abstract

Through an $\hbar$-expansion of the confined Calogero model with spin exchange interactions, we extract a generating function for the involutive conserved charges of the Frahm-Polychronakos spin chain. The resulting conservation laws possess the spin chain yangian symmetry, although they are not expressible in terms of these yangians.