The T2K Collaboration presents the first measurement of electron neutrino-induced charged-current pion production on a predominantly carbon target in a restricted kinematical phase space. This is performed using data from the 2.5° off-axis near detector, ND280. The differential cross sections with respect to the outgoing electron and pion kinematics, in addition to the total flux-integrated cross section, are obtained. Comparisons between the measured and predicted cross-section results using the eut, enie, and uro Monte Carlo event generators are presented. The measured total flux-integrated cross section is [ 2.52 ± 0.52 ( stat ) ± 0.30 ( syst ) ] × 10 − 39 cm 2 nucleon − 1 , which is lower than the event generator predictions
