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arXiv · astro-ph/0312061

An extragalactic HII region in the Virgo cluster

L. Cortese·G. Gavazzi·A. Boselli·J. Iglesias-Paramo
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Abstract

We present spectroscopic observations for six emission-line objects projected onto the Virgo cluster. These sources have been selected from narrow band (Hα+[NII]) images showing faint detectable continuum emission and EW>100 Angstrom. Five of these sources result [OIII]λ5007 emitters at z ~ 0.31, while one 122603+130724 is confirmed to be an HII region belonging to the Virgo cluster. This point-like source has a recessional velocity of ~ 200 km/s, and is associated with the giant galaxy VCC873 (NGC 4402). It has a higher luminosity, star formation rate and metallicity than the extragalactic HII region recently discovered near the Virgo galaxy VCC836 by Gerhard et al. (2002).

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L. Cortese, G. Gavazzi, A. Boselli, J. Iglesias-Paramo. 2003-12-02. An extragalactic HII region in the Virgo cluster. https://doi.org/10.1051/0004-6361%3A20031755

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