  Approximately 30% of luminous red giants exhibit a Long Secondary Period
(LSP) of variation in their light curves, in addition to a shorter primary
period of oscillation. The cause of the LSP has so far defied explanation:
leading possibilities are binarity and a nonradial mode of oscillation. Here,
large samples of red giants in the Large Magellanic Cloud both with and without
LSPs are examined for evidence of an 8 or 24 $\mu$m mid-IR excess caused by
circumstellar dust. It is found that stars with LSPs show a significant mid-IR
excess compared to stars without LSPs. Furthermore, the near-IR $J$-$K$ color
seems unaffected by the presence of the 24 $\mu$m excess. These findings
indicate that LSPs cause mass ejection from red giants and that the lost mass
and circumstellar dust is most likely in either a clumpy or a disk-like
configuration. The underlying cause of the LSP and the mass ejection remains
unknown.
