Edmonds, Peter D.Heinke, Craig O.Grindlay, Jonathan E.Gilliland, and L.2019-09-252001Edmonds, Peter D., Craig O. Heinke, Jonathan E. Grindlay, and Ronald L. Gilliland. 2002. “[ITAL]Hubble Space Telescope[/ITAL] Detection of a Quiescent Low-Mass X-Ray Binary Companion in 47 Tucanae.” The Astrophysical Journal 564 (1): L17–20. https://doi.org/10.1086/338776.0004-637X1538-4357http://nrs.harvard.edu/urn-3:HUL.InstRepos:41399868We present the results of a search for optical counterparts to the two quiescent low-mass X-ray binaries (X5 and X7) in the globular cluster 47 Tucanae, using high-quality Chandra and Hubble Space Telescope images. A faint blue (V=21.7; U-V=0.9) star within 0".03 of the eclipsing system X5 shows variability on both short and long timescales and is the counterpart of the X-ray source. The colors and variability of this object are consistent with the combination of light from an accretion disk and a red main-sequence star (possibly somewhat larger than a normal main-sequence star with similar luminosity). No evidence is found for a star showing either variability or unusual colors near the position of X7, but a probable chance superposition of a star with V=20.25 limits the depth of our search.en-USJournal Article2019-09-2510.1086/338776