SearcharxivSearch

arXiv · astro-ph/9711165

Globular Clusters in Elliptical Galaxies: Constraints on Mergers

Abstract

Understanding the formation of globular clusters will help us to constrain the evolutionary history of galaxies. For mergers on-going today, it appears that the number of newly created proto-globulars varies with the progenitor types and that the percentage increase in the total cluster population is 100% or less. Elliptical galaxies, which are generally thought to be the end-result of such mergers, often show evidence for two populations of globular clusters. This has been taken as support for the merger picture but we show that there are several problems when examined in detail. Strong evidence for an elliptical galaxy with a single population of globular clusters is also presented. Implications for galaxy formation are briefly mentioned.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Duncan Forbes. 1997-11-14. Globular Clusters in Elliptical Galaxies: Constraints on Mergers. https://arxiv.org/abs/astro-ph/9711165

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

On binary pulsars and the force of gravity

The energy-momentum budget of the astrophysical systems can be studied by the exact local conservation equation derived by Landau and Lifshitz. We show that a similar equation is valid for the Einstein-Cartan gravity. We reanalyze a binary pulsar system using the Landau-Lifshitz conservation equation and show that the orbital period change rate can be completely understood as a curvature backreaction process. Taking into account the detailed theoretical and observational research of relativistic binary pulsar systems, especially the system of Hulse and Taylor, we conclude that general relativity and astrophysical observations rule out the existence of gravitational radiation. We comment upon the LIGO GW events and their alternative explanation, as well as the recent pulsar timing arrays data.

astro-ph

Oscillation frequencies and mode lifetimes in alpha Centauri A

We analyse our recently-published velocity measurements of alpha Cen A (Butler et al. 2004). After adjusting the weights on a night-by-night basis in order to optimize the window function to minimize sidelobes, we extract 42 oscillation frequencies with l=0 to 3 and measure the large and small frequency separations. We give fitted relations to these frequencies that can be compared with theoretical models and conclude that the observed scatter about these fits is due to the finite lifetimes of the oscillation modes. We estimate the mode lifetimes to be 1-2 d, substantially shorter than in the Sun.

astro-ph

Hipparcos period-luminosity relations for Miras and semiregular variables

We present period-luminosity diagrams for nearby Miras and semiregulars, selecting stars with parallaxes better than 20 per cent and well-determined periods. Using K-band magnitudes, we find two well-defined P-L sequences, one corresponding to the standard Mira P-L relation and the second shifted to shorter periods by a factor of about 1.9. The second sequence only contains semiregular variables, while the Mira sequence contains both Miras and semiregulars. Several semiregular stars show double periods in agreement with both relations. The Whitelock evolutionary track is shown to fit the data, indicating that the semiregulars are Mira progenitors. The transition between the two sequences may correspond to a change in pulsation mode or to a change in the stellar structure. Large amplitude pulsations leading to classical Mira classification occur mainly near the tip of the local AGB luminosity function.

astro-ph