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We present time-resolved spectroscopy of the optical counterpart to theproposed ultra-compact binary system V407 Vul (=RX J1914.4+2456). Our Geminispectra resolve the 9.48 minute periodicity that has previously been reportedfor this source. We find that the optical counterpart is dominated by areddened late-type spectrum of type G9V and contains solely unresolvedabsorption features. No radial velocity signatures exceeding 10 km/s could bedetected on periods from minutes to hours. Using interstellar extinctionestimates, we derive a distance to the G9 star of 1.1-3.5 kpc. In addition tothis stellar spectrum, we detect a blue component that modulates solely on the9.48 minute period, and peaks ~0.15 in phase ahead of the X-ray peak. This bluecomponent which contributes up to 40% of the light shows no evidence foremission line features that are the usual hallmarks of an interacting binary.Good seeing images obtained with the Magellan telescopes indicate that thevariable and the G-star are aligned to better than 0.1". Despite the lowprobability of a chance alignment of a field star along the line of sight, theG9 light cannot be directly associated with the 9.48 minute variable thatpowers the luminous (~10^35 ergs/s) and highly variable X-ray source. Theoutlook for the detection of conclusive radial velocity measurements willremain challenging due to the extinction along the line of sight in conjunctionwith the contaminating effect of the G9V star.Comment: 8 pages, 4 figures, accepted for publication in the Astrophysical  Journa

GEMINI Spectroscopy of the Ultracompact Binary Candidate V407 Vulpeculae