  The unique eclipsing, weak-lined T Tauri star KH 15D has been detected as an
X-ray source in a 95.7 ks exposure from the Chandra X-ray Observatory archives.
A maximum X-ray luminosity of 1.5 x 10^{29} erg s$^{-1}$ is derived in the
0.5--8 keV band, corresponding to L_{X}/L_bol = 7.5 x 10^{-5}. Comparison with
samples of stars of similar effective temperature in NGC 2264 and in the Orion
Nebula Cluster shows that this is about an order of magnitude low for a typical
star of its mass and age. We argue that the relatively low luminosity cannot be
attributed to absorption along the line of sight but implies a real deficiency
in X-ray production. Possible causes for this are considered in the context of
a recently proposed eccentric binary model for KH 15D. In particular, we note
that the visible component rotates rather slowly for a weak-lined T Tauri star
and has possibly been pseudosynchronized by tidal interaction with the primary
near periastron.
