Based on observations collected at the European Southern Observatory, Chile, Programs 072.A-0454, 076.A-0775.

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IRAF is distributed by the National Optical Astronomy Observatories, which are operated by the Association of Universities for Research in Astronomy, Inc., under the cooperative agreement with the National Science Foundation.

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... pages

http://www.eso.org/instruments/isaac/

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...Willis & Courbin (2005)

We note that all data used in Fig. 2 suffer from very large error bars, not shown. One source of error comes from the way the comoving volume sampled by the NB imaging survey is computed. Willis & Courbin (2005) correctly compute the comoving volume as a function of the Ly ${\alpha}$ luminosity (and line width), while other authors compute a fixed comoving volume from the full width at half maximum of the NB filter. Such differences could significantly affect the luminosity function derived from number counts, and in particular the faint end slope of the LF. For consistency with other work, we have used the traditional way of computing the comoving volume when plotting our datapoint in Fig. 2, and we adapted the Willis & Courbin (2005) datapoint accordingly.

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