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تسجيل مستخدم جديدBright galaxies at Hubbles redshift detection frontier: Preliminary results and design from the redshift z~9-10 BoRG pure-parallel HST survey
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We present the first results and design from the redshift z~9-10 Brightest of the Reionizing Galaxies {it Hubble Space Telescope} survey BoRG[z9-10], aimed at searching for intrinsically luminous unlensed galaxies during the first 700 Myr after the Big Bang. BoRG[z9-10] is the continuation of a multi-year pure-parallel near-IR and optical imaging campaign with the Wide Field Camera 3. The ongoing survey uses five filters, optimized for detecting the most distant objects and offering continuous wavelength coverage from {lambda}=0.35{mu}m to {lambda}=1.7{mu}m. We analyze the initial ~130 arcmin$^2$ of area over 28 independent lines of sight (~25% of the total planned) to search for z>7 galaxies using a combination of Lyman break and photometric redshift selections. From an effective comoving volume of (5-25) $times 10^5$ Mpc$^3$ for magnitudes brighter than $m_{AB}=26.5-24.0$ in the $H_{160}$-band respectively, we find five galaxy candidates at z~8.3-10 detected at high confidence (S/N>8), including a source at z~8.4 with mAB=24.5 (S/N~22), which, if confirmed, would be the brightest galaxy identified at such early times (z>8). In addition, BoRG[z9-10] data yield four galaxies with $7.3 lesssim z lesssim 8$. These new Lyman break galaxies with m$lesssim26.5$ are ideal targets for follow-up observations from ground and space based observatories to help investigate the complex interplay between dark matter growth, galaxy assembly, and reionization.
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