Long-lived highly charged particles at Run 3 and High Luminosity LHC

We investigate the discovery prospects for scalar and fermionic particles with electric charges $1\mathrm{e} \le |Q| \le 8\mathrm{e}$ that are singlet under $ \mathrm{SU}(2)_L $. We calculate lower mass bounds for open channel production mode coming from ATLAS/CMS and MoEDAL experiments, and limits from searches for positronium-like bound states (closed channel) decaying to two photons. Open channel searches by ATLAS and CMS are more sensitive for $1\mathrm{e} \le |Q|\le 5\mathrm{e}$, while closed channel searches prevail for $6 \mathrm{e} \le |Q| \le 8\mathrm{e}$. Sensitivity of MoEDAL is comparable to large experiments for charges $4\mathrm{e} \le |Q| \le 7\mathrm{e}$, and has the potential to even outperform ATLAS and CMS during the HL-LHC phase. The predicted lower mass bounds for Run 3 LHC span from 590 (940) GeV for $|Q|=1\mathrm{e}$ to 2190 (2320) GeV for $|Q|=8\mathrm{e}$ for scalars (fermions). In case of the HL-LHC limits are 630 (990) GeV for $|Q|=1\mathrm{e}$ to 2480 (2620) GeV for $|Q|=8\mathrm{e}$ for scalar (fermionic) particles.