  With the uniquely high contrast within 0.1" (\Delta mag(L') = 5-6.5
magnitudes) available using Sparse Aperture Masking (SAM) with NACO at VLT, we
detected asymmetry in the flux from the Herbig Fe star HD 142527 with a
barycenter emission situated at a projected separation of 88+/-5 mas
(12.8+/-1.5 AU at 145 pc) and flux ratios in H, K, and L' of 0.016+/-0.007,
0.012+/-0.008, 0.0086+/-0.0011 respectively (3-\sigma errors) relative to the
primary star and disk. After extensive closure-phase modeling, we interpret
this detection as a close-in, low-mass stellar companion with an estimated mass
of ~0.1-0.4 M_Sun. HD 142527 has a complex disk structure, with an inner gap
imaged in both the near and mid-IR as well as a spiral feature in the outer
disk in the near-IR. This newly detected low-mass stellar companion may provide
a critical explanation of the observed disk structure.
