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arXiv · astro-ph/9807072

Optical and CO Radio Observations of Poor Cluster Zwicky 1615.8+3505

A. Tomita·H. Maehara·T. T. Takeuchi·K. Nakanishi·M. Honma·Y. Tutui·Y. Sofue
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Abstract

The cluster Zwicky 1615.8+3505 is considered to be a dynamically young poor cluster. To investigate the morphology and star-formation activity of galaxies under the environment of a dynamically young poor cluster, we have performed V, R, and I surface photometry, optical low-resolution spectroscopy, and 12CO (J=1-0) line observations for member galaxies. Our data show that more than 90% of the observed galaxies show regular morphologies and no star-formation activities, indicating that the environment does not affect these galaxy properties. Among sixteen galaxies observed, only NGC 6104 shows a significant star-formation activity, and shows a distorted morphology, indicating a tidal interaction. This galaxy contains double knots, and only one knot possesses Seyfert activity, though the sizes and luminosities are similar to each other; we also discuss this feature.

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A. Tomita, H. Maehara, T. T. Takeuchi, K. Nakanishi, M. Honma, Y. Tutui, Y. Sofue. 1999-04-28. Optical and CO Radio Observations of Poor Cluster Zwicky 1615.8+3505. https://doi.org/10.1093/pasj%2F51.3.285

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