Ultra-strong MgII absorbers trace both inflowing and outflowing gas: insights from dual down-the-barrel and quasar sightlines

Antonia Fernández-Figueroa, Glenn G. Kacprzak, Tania M. Barone +4

We present Keck/LRIS spectroscopy of seven isolated galaxy-quasar pairs at $0.4\le z\le 0.6$, each exhibiting ultra-strong MgII absorption ($W_{r,2796}\ge 3$ Å), probing both…