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We present spectroscopic observations with VLT/XSHOOTER and Subaru/MOIRCS ofa relatively bright Y-band drop-out galaxy in the Hubble Ultra Deep Field,first selected by Bunker et al. (2010), McLure et al. (2010) and Bouwens et al.(2010) to be a likely z~8-9 galaxy on the basis of its colours in the HST ACSand WFC3 images. This galaxy, HUDF.YD3 (also known as UDFy-38135539) has beentargetted for VLT/SINFONI integral field spectroscopy by Lehnert et al. (2010),who published a candidate Lyman-alpha emission line at z=8.55 from this source.In our independent spectroscopy using two different infrared spectrographs (5hours with VLT/XSHOOTER and 11 hours with Subaru/MOIRCS) we are unable toreproduce this line. We do not detect any emission line at the spectral andspatial location reported in Lehnert et al. (2010), despite the expected signalin our combined MOIRCS & XSHOOTER data being 5-sigma. The line emission alsoseems to be ruled out by the faintness of this object in recently extremelydeep F105W (Y-band) HST/WFC3 imaging from HUDF12; the line would fall withinthis filter and such a galaxy should have been detected at Y(AB)=28.6mag (~20sigma) rather than the marginal Y(AB)~30mag observed in the Y-band image, >3times fainter than would be expected if the emission lie was real. Hence itappears highly unlikely that the reported Lyman-alpha line emission at z>8 isreal, meaning that the highest-redshift sources for which Lyman-alpha emissionhas been seen are at z=6.9-7.2. It is conceivable that Lyman-alpha does notescape galaxies at higher redshifts, where the Gunn-Peterson absorption rendersthe Universe optically thick to this line. However, deeper spectroscopy on alarger sample of candidate z>7 galaxies will be needed to test this.

VLT/XSHOOTER & Subaru/MOIRCS Spectroscopy of HUDF-YD3: No Evidence for Lyman-alpha Emission at z=8.55