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arXiv · 1002.1103

Peanut-shaped bulges in face-on disk galaxies

J. Mendez-Abreu·E. M. Corsini·V. P. Debattista·S. De Rijcke·J. A. L. Aguerri·A. Pizzella
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Abstract

We present high resolution absorption-line spectroscopy of 3 face-on galaxies, NGC 98, NGC 600, and NGC 1703 with the aim of searching for box/peanut (B/P)-shaped bulges. These observations test and confirm the prediction of Debattista et al. (2005) that face-on B/P-shaped bulges can be recognized by a double minimum in the profile of the fourth-order Gauss-Hermite moment h_4. In NGC 1703, which is an unbarred control galaxy, we found no evidence of a B/P bulge. In NGC 98, a clear double minimum in h_4 is present along the major axis of the bar and before the end of the bar, as predicted. In contrast, in NGC 600, which is also a barred galaxy but lacks a substantial bulge, we do not find a significant B/P shape.

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J. Mendez-Abreu, E. M. Corsini, V. P. Debattista, S. De Rijcke, J. A. L. Aguerri, A. Pizzella. 2010-02-05. Peanut-shaped bulges in face-on disk galaxies. https://arxiv.org/abs/1002.1103

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