Baker-Akhiezer function for the deformed root system $BC(l,1)$ and bispectrality

Iain McWhinnie, Liam Rooke, Martin Vrabec

We show that a Sergeev-Veselov difference operator of rational Macdonald-Ruijsenaars (MR) type for the deformed root system $BC(l,1)$ preserves a ring of quasi-invariants in the ca…