  A data sample of events from proton-proton collisions with two isolated
same-sign leptons, missing transverse momentum, and jets is studied in a search
for signatures of new physics phenomena by the CMS Collaboration at the LHC.
The data correspond to an integrated luminosity of 35.9 inverse femtobarns, and
a center-of-mass energy of 13 TeV. The properties of the events are consistent
with expectations from standard model processes, and no excess yield is
observed. Exclusion limits at 95% confidence level are set on cross sections
for the pair production of gluinos, squarks, and same-sign top quarks, as well
as top-quark associated production of a heavy scalar or pseudoscalar boson
decaying to top quarks, and on the standard model production of events with
four top quarks. The observed lower mass limits are as high as 1500 GeV for
gluinos, 830 GeV for bottom squarks. The excluded mass range for heavy
(pseudo)scalar bosons is 350-360 (350-410) GeV. Additionally, model-independent
limits in several topological regions are provided, allowing for further
interpretations of the results.
