Aging Star Clusters Nick DiPreta. Globular Clusters Similar age 50 to 300 light years across...
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Transcript of Aging Star Clusters Nick DiPreta. Globular Clusters Similar age 50 to 300 light years across...
Aging Star Clusters
Nick DiPreta
Globular Clusters• Similar age • 50 to 300 light years across• Hundreds to 200 million stars• Formed when the universe was young
Hercules Cluster http://www.rc-astro.com/php/phpthumb/cache/phpThumb_cache_rc-astro.com_srce4d4565e800c0a1c8e17c177a7713b4e_par0ddf367c5f01d9ba090bf356b6761f52_dat1208719109.jpeg
Knowledge Base Cont.Open Clusters
• Stars have relatively Same age• Similar Chemical Composition• Composed of Younger Stars which are bright and
can be easily observed
Pleiades http://apod.nasa.gov/apod/image/0711/pleiades_fs_big.jpg
Mass Segregation
• Larger Stars move towards center• Smaller stars move towards outer edges
Minimum Spanning Tree
• Prim algorithm
• Can be automated in excel
5
4
3
A B
C
Using The Minimum Spanning Tree to Trace Mass Segregation
• quantified mass segregation
Richard J. Allison 2009
Metallicity
• Heavier metals are created over time
• Shows amount of fusion that has occurred
• Shows age
Stellar Rotation
• proposed indirect measure of stellar age
• slows down as the star ages
• Can be measured using light curves- measurements of periodicity in photometric luminosity
Stellar Ages From Stellar RotationMeiborn
2008
blue red
• Mass segregation patterns found of single stars in Pleiades
Raboud and Milliad(2000)
Purpose
• To determine if stellar mass segregation occurs over time, and if so why. Also, to see if there is a relationship between age and mass segregation.
• To explore and determine the relationship between radial velocity and age.
Methodology Candidates Images obtained using CCD imager
Images processed and sharpened using photoshop
MST calculated using Prim algorithm
Mass Segregation Formula by Richard J Allison
Metallicity taken from surveys using National Virtual
Observatory
Rotational velocity taken photometrically in 3hrs/ hr for the full period of rotation of specific stars within a cluster n=40 (duration to be determined)
APT used to determine luminosity
Change in luminosity plotted to form light curve and determine rate of rotation
Compared to
Images obtained using CCD imager
Images processed and sharpened using photoshop
Candidates
M39
M29
M103
M52
NGC 457
NGC 663
NGC 7790
NGC 7788
NGC 7209
NGC 7243
Pleiades- M45
Beehive Cluster- M44
Perseus Double Cluster-NGC 869 884
The Butterfly Cluster or M6
M34
M35
M47
M46
Jewel Box Cluster- NGC 4755
Ptolemy Cluster- M7
Bibliography• 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 • 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
• 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..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• 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 • 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
• Meibom, Søren. "Stellar Ages from Stellar Rotation." Proceedings of the International Astronomical Union 4.S258 (2008): 357.