Halavanau, A. Baturin, S. Ding, Y. Mayes, C.E. Piot, P. JACoW Publishing Geneva, Switzerland 2673-5490 978-3-95450-213-4 10.18429/JACoW-IPAC2020-WEVIR06 English 49-52 electron linac simulation cathode laser Contribution to a conference proceedings 2020 2020-06 https://doi.org/10.18429/JACoW-IPAC2020-WEVIR06 https://jacow.org/ipac2020/papers/wevir06.pdf Photoinjectors have demonstrated the capability of electron beam transverse tailoring, enabled by the microlens array (MLA) setup. For instance, electron beams, transversely segmented into periodic beamlet formations, were successfully produced in several experiments at Argonne Wakefield Accelerator (AWA). In this proceeding, we discuss necessary steps to demonstrate the hollow electron beam generation, with an arbitrary diameter and width with the MLA. We also present beam dynamics simulations and highlight key features of the hollow beam transport in LCLS copper linac.