  In this paper, the detectability of habitable exomoons orbiting around giant
planets in M-dwarf systems using Transit Timing Variations (TTVs) and Transit
Timing Durations (TDVs) with Kepler-class photometry is investigated. Light
curves of systems with various configurations were simulated around M-dwarf
hosts of mass 0.5 Msun and radius 0.55 Rsun. Jupiter-like giant planets which
offer the best potential for hosting habitable exomoons were considered with
rocky super-Earth-mass moons. The detectability is measured by using the
phase-correlation between TTV and TDV signals. Since the TDV signal is
typically weaker than the TTV signal, confirmation of an exomoon detection will
depend on being able to detect a TDV signal. We find that exomoons around
planets orbiting within the habitable zone of an M-dwarf host star can produce
both detectable TTV and TDV signatures with Kepler-class photometry. While
aliasing between the planet period and moon period may hinder exomoon
detection, we also find some strong correlation signatures in our simulation
(eg. correlation: >0.7) which would provide convincing exomoon signatures. With
the addition of red noise stellar variability, correlations generally weaken.
However simulated examples with planet masses less than around 25 Mearth, moons
of mass 8-10 Mearth and specific values of planet and moon periods still yield
detectable correlation in 25-50% of cases. Our simulation indicates that Kepler
provides one of the best available opportunities for exomoon detection.
