The Oxygen-ii Luminosity Density of the Universe 1
نویسندگان
چکیده
Equivalent widths of O II] 3727 A lines are measured in 375 faint galaxy spectra taken as part of the Caltech Faint Galaxy Redshift Survey centered on the Hubble Deep Field. The sensitivity of the survey spectra to the O II] line is computed as a function of magnitude, color and redshift. The luminosity function of galaxies in the O II] line and the integrated luminosity density of the Universe in the O II] line are computed as a function of redshift. It is found that the luminosity density in the O II] line was a factor of 10 higher at redshifts z 1 than it is at the present day. The simplest interpretation is that the star formation rate density of the Universe has declined dramatically since z 1.
منابع مشابه
ar X iv : a st ro - p h / 98 04 12 9 v 1 1 4 A pr 1 99 8 The oxygen - II luminosity density of the Universe 1
Equivalent widths of [O II] 3727 Å lines are measured in 375 faint galaxy spectra taken as part of the Caltech Faint Galaxy Redshift Survey centered on the Hubble Deep Field. The sensitivity of the survey spectra to the [O II] line is computed as a function of magnitude, color and redshift. The luminosity function of galaxies in the [O II] line and the integrated luminosity density of the Unive...
متن کاملar X iv : a st ro - p h / 98 04 12 9 v 1 1 4 A pr 1 99 8 The oxygen - II luminosity density of the Universe
Equivalent widths of [O II] 3727 Å lines are measured in 375 faint galaxy spectra taken as part of the Caltech Faint Galaxy Redshift Survey centered on the Hubble Deep Field. The sensitivity of the survey spectra to the [O II] line is computed as a function of magnitude, color and redshift. The luminosity function of galaxies in the [O II] line and the integrated luminosity density of the Unive...
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