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Young Stellar Nuclei in the Lenticular Galaxies. I. NGC 1023 and NGC 7332

Olga K. Sil'chenko
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Abstract

As a result of bidimensional spectroscopy of the central parts of two nearby lenticular galaxies, NGC 1023 and NGC 7332, undertaken with the Multi-Pupil Field Spectrograph of the 6m telescope of the Special Astrophysical Observatory, their chemically decoupled stellar nuclei are found to be substantially younger than the surrounding bulges: the mean age of the nuclear stellar populations is 7 billion years in NGC 1023 and 2.5 +/- 0.5 billion years in NGC 7332. The morphological analysis undertaken by Seifert and Scorza (1996) for NGC 7332 and by us for NGC 1023 has revealed a existence of separate circumnuclear stellar disks with the radius of 80 pc in NGC 1023 and of 400 pc in NGC 7332; probably, the intermediate-age stellar populations are related to these structures.

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Olga K. Sil'chenko. 1999-04-20. Young Stellar Nuclei in the Lenticular Galaxies. I. NGC 1023 and NGC 7332. https://doi.org/10.1086/300876

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