We present a deep H-band image of the field of a candidate Ζ = 10 galaxy magnified by the foreground (Ζ = 0.25) cluster A1835. The image was obtained with NIRi on Gemini-North to better constrain the photometry and investigate the morphology of the source. The image is approximately 1 mag deeper and has better spatial resolution (seeing was 0.4″-0.5″) than the existing H-band image obtained with ISAAC on the Very Large Telescope by Pello et al. The object is not detected in our new data. Given the published photometry (H_(AB) = 25.0), we would have expected it to have been detected at more than ～7 σ in a 1.4″ diameter aperture. We obtain a limit of H_(AB) > 26.0 (3 σ) for the object. A major part of the evidence that this object is at z = 10 was the presence of a strong continuum break between the J and H bands, attributed to absorption of all continuum shortward of 1216 A in the rest frame of the object. Our H-band nondetection substantially reduces the magnitude of any break and therefore weakens the case that this object is at z = 10. Without a clear continuum break, the identification of an emission line at 1.33745 μm as Lyα at z ≈ 10 is less likely. We show that the width and flux of this line are consistent with ah alternative emission line such as [O Ⅲ] λ5007 from an intermediate-redshift H Ⅱ/dwarf galaxy.
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