We present near-infrared (NIR; J and K s) survey of the Great Observatories Origins Deep Survey-North (GOODS-N) field. The publicly available imaging data were obtained using the MOIRCS instrument on the 8.2?m Subaru and the WIRCam instrument on the 3.6?m Canada-France-Hawaii Telescope (CFHT). These observations fulfill a serious wavelength gap in the GOODS-N data, i.e., lack of deep NIR observations. We combine the Subaru/MOIRCS and CFHT/WIRCam archival data to generate deep J- and K s-band images, covering the full GOODS-N field (~169 arcmin2) to an AB magnitude limit of ~25?mag (3σ). We applied z 850-band dropout color selection criteria, using the NIR data generated here. We have identified two possible Lyman break galaxy (LBG) candidates at z 6.5 with J 24.5. The first candidate is a likely LBG at z 6.5 based on a weak spectral feature tentatively identified as Lyα line in the deep Keck/DEIMOS spectrum, while the second candidate is a possible LBG at z 7 based on its photometric redshift. These z 850-dropout objects, if confirmed, are among the brightest such candidates found so far. At z 6.5, their star formation rate is estimated as 100-200 M ☉?yr–1. If they continue to form stars at this rate, they assemble a stellar mass of ~5 × 1010 M ☉ after about 400 million years, becoming the progenitors of massive galaxies observed at z 5. We study the implication of the z 850-band dropout candidates discovered here, in constraining the bright end of the luminosity function and understanding the nature of high-redshift galaxies.
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