The 3.5 keV X-ray line signal from decaying moduli with low cutoff scale
  The recent unidentified 3.5 keV X-ray line signal can be explained by
decaying moduli dark matter with a cutoff scale one order of magnitude smaller
than the Planck scale. We show that such modulus field with the low cutoff
scale follows a time-dependent potential minimum and its abundance is reduced
by the adiabatic suppression mechanism. As a result the modulus abundance can
naturally be consistent with the observed dark matter abundance without any
fine-tuning of the initial oscillation amplitude.
