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High resolution science with high redshift galaxies

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 نشر من قبل Rolf Jansen
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف R.A. Windhorst




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We summarize the high-resolution science that has been done on high redshift galaxies with Adaptive Optics (AO) on the worlds largest ground-based facilities and with the Hubble Space Telescope (HST). These facilities complement each other. Ground-based AO provides better light gathering power and in principle better resolution than HST, giving it the edge in high spatial resolution imaging and high resolution spectroscopy. HST produces higher quality, more stable PSFs over larger field-of-views in a much darker sky-background than ground-based AO, and yields deeper wide-field images and low-resolution spectra than the ground. Faint galaxies have steadily decreasing sizes at fainter fluxes and higher redshifts, reflecting the hierarchical formation of galaxies over cosmic time. HST has imaged this process in great structural detail to z<~6, and ground-based AO and spectroscopy has provided measurements of their masses and other physical properties with cosmic time. Last, we review how the 6.5 meter James Webb Space Telescope (JWST) will measure First Light, reionization, and galaxy assembly in the near--mid-IR after 2013.

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