Stellar Velocity Profiles and Line-Strengths out to Four Effective Radii in the Early-Type Galaxy NGC 3379

A. Weijmans; M. Cappellari; P. T. de Zeeuw; E. Emsellem; J. Falcon-Barroso; H. Kuntschner; R. M. McDermid; R. C. E. van den Bosch; G. van de Ven

arXiv · 0811.2840

Stellar Velocity Profiles and Line-Strengths out to Four Effective Radii in the Early-Type Galaxy NGC 3379

A. Weijmans·M. Cappellari·P. T. de Zeeuw·E. Emsellem·J. Falcon-Barroso·H. Kuntschner·R. M. McDermid·R. C. E. van den Bosch·G. van de Ven

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Abstract

We describe a new technique to measure stellar kinematics and line-strengths at large radii in nearby galaxies. Using the integral-field spectrograph SAURON as a 'photon-collector', we obtain spectra out to four effective radii (Re) in the early-type galaxy NGC 3379. By fitting orbit-based models to the extracted stellar velocity profile, we find that ~40% of the total mass within 5 Re is dark. The measured absorption line-strengths reveal a radial gradient with constant slope out to 4 Re.

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A. Weijmans, M. Cappellari, P. T. de Zeeuw, E. Emsellem, J. Falcon-Barroso, H. Kuntschner, R. M. McDermid, R. C. E. van den Bosch, G. van de Ven. 2008-11-18. Stellar Velocity Profiles and Line-Strengths out to Four Effective Radii in the Early-Type Galaxy NGC 3379. https://arxiv.org/abs/0811.2840

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