The role of the $qqqq\bar{q}$ components in the electromagnetic transition ${\gamma }^{\ast }N\to N^{\ast }(1535)$

C. S. An, B. S. Zou

The helicity amplitudes $A_{1/2}^p$ and $S_{1/2}^p$ for the electromagnetic transition ${\gamma }^{\ast }N\to N^{\ast }(1535)$ are calculated in the quark model that is extended to include th…