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Table 2.

Percentiles of the distribution of Hα + [NII] background levels.

Quantity Percentiles
5 50 95
Counts 27 52 210
Vega magnitude
(mag arcsec−2) 20.6 19.9 18.3
Surface brightness
(10−15 erg cm−2 s−1 arcsec−2) 0.91 1.7 7.4

Notes. These are pipeline-computed values obtained for uniformly calibrated images. The sample used here numbers 63956 CCD frames (or 15989 WFC exposures). Not included are the 36808 CCD frames (9202 WFC exposures) for which only the pipeline photometric calibration is available.

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