1. Knowledge Base A B C Literature Review Goals Determine if there is mass segregation in open clusters To look for a correlation between mass segregation and metallicity. 3 4 5 Globular star clusters are dense bunches of hundreds of thousands of stars of about the same age and have some of the oldest surviving stars in the universe as compared to open clusters which are much less dense and younger. Stars within a cluster have similar age to each other which allows for differences between them to be attributed to mass and evolution rather than age, which serves as the main reasoning for astronomers researching them (they help give better insight into galaxy formation and stellar evolution as a whole). (M80 left/ M39 right) The prim algorithm (left) enables us to create the minimum spanning tree. Prim’s algorithm requires one to connect stars in a cluster from point to point in the shortest manner possible. The average massive to massive star MST and normal MST weights will allow us to put these numbers into the mass segregation ratio. Although energy can exchange in either direction, there is a statistical tendency for the kinetic energy of the two members to equalize during an encounter; this statistical phenomenon is called equipartition. The heavier members will thus tend to sink into lower (closer to the center) orbits, while the lighter members will tend to rise to higher orbits. When mass segregation is complete, the cluster will enter a “relaxed” state, in which several distinct layers of stars of different masses are present. M45-open M11-open M3- globular Mass segregation ratio developed by Richard J. Allison used in combination with the prim algorithm to determine the mass segregation ratio. Age difference between clusters correlates to the separation of the clusters suggesting that mass segregation is present.

2. Methodology Candidate Selection based on criteria n=12 Images processed and sharpened using ImageJ MST calculated using Prim algorithm Mass Segregation Ratio by Richard J Allison Search for correlation between Metallicity and Mass Segregation Metallicity taken from L. Chen’s Catalog of Open Clusters Distance Calculated using distance formula Images obtained from 2mass Results

3. Discussion Conclusion Bibliography In conclusion 5 of the 12 open clusters were mass segregated, 4 of them were inversely mass segregated and 3 of the open clusters were not mass segregated at all Supports Raboud that mass segregation is not related to equipartition of kinetic energy The data was unexpected because a correlation between mass segregation and metallicity was expected Graphs appears slightly cyclic in nature Data had a stronger correlation when first separated by age The Columbia Encyclopedia, Sixth Edition Copyright ©2004, Columbia University Press. Licensed from Lernout & Hauspie Speech Products N.V. All Rights Reserved. http://www.questia.com/library/encyclopedia/star_cluster.jsp http://www.questia.com/library/encyclopedia/star_cluster.jsp Eugenio Carretta “Abundances in Red Giant Stars of NGC 2808 and Correlations between Chemical Anomalies and Global Parameters in Globular Clusters.” Osservatorio Astronomico di Bologna. The Astronomical Journal, 2006 March. http://adsabs.harvard.edu/abs/2006AJ....131.1766C Lee, H.; Kim, S.-L.; Kim, H.-J. ; Jeon, Y.-B.; Park, H,-S. “New Variable Stars in the Open Cluster M103.” Konkoly Observatory, Budapest, 26 October 2005, Dept. of Earth Science Education, Korea National University of Education, Korea Astronomy and Space Science Institute. http://adsabs.harvard.edu/abs/2005IBVS.5656....1L http://adsabs.harvard.edu/abs/2005IBVS.5656....1L Gonzalo Alcaino and William Liller “Ages of Globular Clusters Derived from BVRI CCD photometry.” Instituto Isaac Newton, Ministerio de Educación de Chile, Santiago, Chile. Societá Astronomica Italiana, Vol 57 No. 3. http://adsabs.harvard.edu/abs/1986MmSAI..57..321Ahttp://adsabs.harvard.edu/abs/1986MmSAI..57..321A Prof. Fabrizio Mazzucconi, Enrico Albisetti and Bernardo Mannucci. “Atlas of The Skies: Journeying between the stars and planets in the discovery of the universe.”TAJ Books 2003 Mike Lynch. “The Essential guide to Our Night Sky: New York Starwatch.” Voyageur Press 2005 p.46 and 47 Elmegreen, Bruce G., Yuri Efremov, Ralph E. Pudritz, and Hans Zinnercker. “Observations and Theory of Star Cluster Formation.” http://www.uapress.arizona.edu/onlinebks/ppiv/chap07.pdf http://www.uapress.arizona.edu/onlinebks/ppiv/chap07.pdf Chandra X-ray Observatory (2008, April 29). Oldest Known Celestial Objects are Surprisingly Immature. Science Daily. Retrieved April 28, 2009, from http://www.sciencedaily.com/releases/2008/04/080428140351.htm http://www.sciencedaily.com/releases/2008/04/080428140351.htm ESA Hubble Information Centre (2008, August 6). Thousands of Globular Clusters Identified in Virgo Cluster of Galaxies. Science Daily. Retrieved April 28, 2009, from http://www.sciencedaily.com/releases/2008/08/080805234054.htm http://www.sciencedaily.com/releases/2008/08/080805234054.htm L. Chen “On the Galactic Disk Metallicity Distribution from Open Clusters. I. New Catalogs and Abundance Gradient “ Retrieved January 20 th from http://www.iop.org/EJ/article/- search=67323939.1/1538-3881/125/3/1397/datafile1.txt?request- id=03792360-92e6-4fea-9709-ade8349a14a5http://www.iop.org/EJ/article/- search=67323939.1/1538-3881/125/3/1397/datafile1.txt?request- id=03792360-92e6-4fea-9709-ade8349a14a5 http://isc.astro.cornell.edu/~spoon/crashcourse/protostellar.disk.jpg