  We investigate the prospect of searching for new physics via the novel
signature of same-sign diboson + ${E\!\!/}_{T}$ at current and future LHC. We
study three new physics models: (i) natural SUSY models, (ii) type-III seesaw
model and (iii) type-II seesaw/Georgi-Machacek model. In the first two class of
models, this signature arises due to the presence of a singly-charged particle
which has lifetime long enough to escape detection, while in the third model
this signature originates resonantly from a doubly-charged particle produced
along with two forward jets that, most likely, would escape detection. We
analyze in great detail the discovery prospects of the signal in these three
classes of models in the current as well as the upcoming runs of the LHC (such
as HL-LHC, HE-LHC and FCC-hh) by showing a distinction among these scenarios.

High Energy Physics - Phenomenology;High Energy Physics - Experiment