On a Certain Subalgebra of $U_q({\widehat{\mathfrak{sl}}}_2)$ Related to the Degenerate $q$-Onsager Algebra

Tomoya Hattai, Tatsuro Ito

In [Kyushu J. Math. 64 (2010), 81-144, arXiv:0904.2889], it is discussed that a certain subalgebra of the quantum affine algebra $U_q({\widehat{\mathfrak{sl}}}_2)$ controls the secon…