The stellar orbit distribution in present-day galaxies inferred from the CALIFA survey
Galaxy formation entails the hierarchical assembly of mass, along with the condensation of baryons and the ensuing, self-regulating star formation. The stars form a collisionless system whose orbit distribution retains dynamical memory that can constrain a galaxy's formation history. The ordere...
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| Main Authors: | , |
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| Format: | Article (Journal) Chapter/Article |
| Language: | English |
| Published: |
2018
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| In: |
Arxiv
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| Online Access: | Verlag, kostenfrei, Volltext: http://arxiv.org/abs/1711.06728
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| Author Notes: | Ling Zhu, Glenn van de Ven, Remco van den Bosch, Hans-Walter Rix, Mariya Lyubenova, Jesús Falcón-Barroso, Marie Martig, Shude Mao, Dandan Xu, Yunpeng Jin, Aura Obreja, Robert J.J. Grand, Aaron A. Dutton, Andrea V. Maccio, Facundo A. Gómez, Jakob C. Walcher, Rubén García-Benito, Stefano Zibetti, Sebastian F. Sánchez |
| Summary: | Galaxy formation entails the hierarchical assembly of mass, along with the condensation of baryons and the ensuing, self-regulating star formation. The stars form a collisionless system whose orbit distribution retains dynamical memory that can constrain a galaxy's formation history. The ordered-rotation dominated orbits with near maximum circularity $\lambda_z \simeq1$ and the random-motion dominated orbits with low circularity $\lambda_z \simeq0$ are called kinematically cold and kinematically hot, respectively. The fraction of stars on `cold' orbits, compared to the fraction of stars on `hot' orbits, speaks directly to the quiescence or violence of the galaxies' formation histories. Here we present such orbit distributions, derived from stellar kinematic maps via orbit-based modelling for a well defined, large sample of 300 nearby galaxies. The sample, drawn from the CALIFA survey, includes the main morphological galaxy types and spans the total stellar mass range from $10^{8.7}$ to $10^{11.9}$ solar masses. Our analysis derives the orbit-circularity distribution as a function of galaxy mass, |
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| Item Description: | Gesehen am 19.03.2018 |
| Physical Description: | Online Resource |