... candidates

Based on observations obtained at the NTT ESO telescope on La Silla (Chile).

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...

Table 2, Figs. 2 and 3 are only available in electronic form at http://www.edpsciences.org

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... package

Munich Image Data Analysis System, which is developed and maintained by the European Southern Observatory.

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... IRAF

IRAF is distributed by NOAO, which is operated by AURA, Inc, under cooperative agreement with the NSF.

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... EW(H $\alpha) >6.0$ $\AA$

We assume here that an emission line has positive EW.

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