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The bar pattern speed of NGC 4431

E. M. Corsini·J. A. L. Aguerri·Victor P. Debattista·A. Pizzella·F. D. Barazza·H. Jerjen
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Abstract

We present surface photometry and stellar kinematics of NGC 4431, a barred dwarf galaxy in the Virgo cluster undergoing a tidal interaction with one of its neighbors, NGC 4436. We measured its bar pattern speed using the Tremaine-Weinberg method, and derived the ratio of the corotation radius, D_L, to the bar semi-major axis, a_B. We found D_L/a_B=0.6^{+1.2}_{-0.4} at 99% confidence level. Albeit with large uncertainty, the probability that the bar ends close to its corotation radius (i.e., 1.0 \leq D_L/a_B \leq 1.4) is about twice as likely as that the bar is much shorter than corotation radius (i.e., D_L/a_B > 1.4).

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E. M. Corsini, J. A. L. Aguerri, Victor P. Debattista, A. Pizzella, F. D. Barazza, H. Jerjen. 2007-03-13. The bar pattern speed of NGC 4431. https://doi.org/10.1086/518035

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