Evidence of Energy Injection in the Short and Distant GRB 250221A in a High Density Environment

Camila Angulo-Valdez, Rosa L. Becerra, Ramandeep Gill +29

We present the photometric and spectroscopic analysis of the short-duration GRB 250221A ($T_{90}=1.80\pm 0.32$ s), using a data set from the optical facilities COLIBRÍ, the Harling…