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 \times 10 ^ { 29 } erg s ^ { -1 } is derived in the 0.5–8 keV band , corresponding to L _ { X } / L _ { bol } = 7.5 \times 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 can not 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 .