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The Most Distant Galaxies

Hyron Spinrad
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Abstract

I review selected current observations of distant galaxies and our interpretation of the fragile (and occasionally contradictory) data. Galaxies at the ``contemporary limit'' of technology and redshift (z~6) are difficult to locate in the first place. Moreover, the large redshift may push some critical confirming and/or interpretative analysis toward unfamiliar IR wavelengths. I will concentrate on observational means and results to explore the early evolution of galaxies. We also note the biases that intrude on plans for the interpretative aspects of distant galaxy photometry and spectroscopy. We discuss the best methods of selection for those very distant systems; these methods include utilizing strong sub-mm emission from dust, photometry indicating a UV "spectral break," and finally the signal of a strong Lyman alpha emission line. This feature has now carried us to a galaxy redshift in excess of z = 6.57!

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Hyron Spinrad. 2003-08-22. The Most Distant Galaxies. https://arxiv.org/abs/astro-ph/0308411

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