University of Surrey

Test tubes in the lab Research in the ATI Dance Research

New insights in the origin and evolution of the old, metal-rich open cluster NGC 6791

Martinez-Medina, Luis A., Gieles, Mark, Pichardo, Barbara and Peimbert, Antonio (2017) New insights in the origin and evolution of the old, metal-rich open cluster NGC 6791 Monthly Notices of the Royal Astronomical Society, 474 (1). pp. 32-44.

New insights in the origin and evolution of the old, metal-rich open cluster NGC 6791.pdf - Accepted version Manuscript

Download (3MB) | Preview


NGC 6791 is one of the most studied open clusters, it is massive (∼5000 M⊙), located at the solar circle, old (∼8 Gyr) and yet the most metal-rich cluster ([Fe/H] ≃ 0.4) known in the Milky Way. By performing an orbital analysis within a Galactic model including spiral arms and a bar, we found that it is plausible that NGC 6791 formed in the inner thin disc or in the bulge, and later displaced by radial migration to its current orbit. We apply different tools to simulate NGC 6791, including direct N-body summation in time-varying potentials, to test its survivability when going through different Galactic environments. In order to survive the 8 Gyr journey moving on a migrating orbit, NGC 6791 must have been more massive, M0 ≥ 5 × 104M⊙, when formed. We find independent confirmation of this initial mass in the stellar mass function, which is observed to be flat; this can only be explained if the average tidal field strength experienced by the cluster is stronger than what it is at its current orbit. Therefore, the birth place and journeys of NGC 6791 are imprinted in its chemical composition, in its mass loss, and in its flat stellar mass function, supporting its origin in the inner thin disc or in the bulge.

Item Type: Article
Divisions : Faculty of Engineering and Physical Sciences > Physics
Authors :
Martinez-Medina, Luis A.
Pichardo, Barbara
Peimbert, Antonio
Date : 24 October 2017
Identification Number : 10.1093/mnras/stx2739
Copyright Disclaimer : © 2017 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society
Uncontrolled Keywords : Galaxy: disc. Galaxy: kinematics and dynamics. Open clusters and associations: general. Open clusters and associations: individual: NGC 6791. Galaxy: structure.
Depositing User : Clive Harris
Date Deposited : 02 Nov 2017 08:39
Last Modified : 14 Mar 2018 13:30

Actions (login required)

View Item View Item


Downloads per month over past year

Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800