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http://zebu.uoregon.edu/~soper/MilkyWay/cepheid.html. http://www.cartage.org.lb/en/themes/Sciences/Astronomy/Thestars/energyprodu ct/EnergyTransport/EnergyTransport.htm ...
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1. J Leon Wilde BGSU March 31st 2005
Pulsating Variable StarsWelcome
2. Pulsating Variable StarsOverview
History of discovery What are pulsating variable stars? Why are they important? Any recent works?
3. Pulsating Variable StarsHistory
1595 David Fabricius o Ceti, 11 months 1784 John Goodricke d Cephei, 5d, 8h, 48min ~1912 Henrietta Leavitt
4. Pulsating Variable StarsHistory
5. Pulsating Variable StarsPVS Physics
Periodic luminosity changes Radial vs Nonradial Pressure wave estimation:
9. Pulsating Variable StarsPVS Physics
10. Pulsating Variable StarsPVS Physics
Classes:
11. Pulsating Variable StarsWho cares?
Very large luminosities Distance calibrations
12. Pulsating Variable StarsRecent work?
Polaris! Period 1844-2004, increase 4.5s/year 1963-1966, brief hiatus Magnitude Prior to 1963, 0.1mag After 1966, sharp decline, 0.05mag Seems to no longer pulsate
13. Pulsating Variable StarsThanks and references
Thanks! References: http://www.adsabs.harvard.edu/ http://zebu.uoregon.edu/~soper/MilkyWay/cepheid.html http://www.cartage.org.lb/en/themes/Sciences/Astronomy/Thestars/energyproduct/EnergyTransport/EnergyTransport.htm http://antwrp.gsfc.nasa.gov/apod/ap981027.html http://astro.wsu.edu/worthey/astro/html/lec-women.html http://www.if.ufrgs.br/oei/stars/aglom/clusters.htm Polaris article: http://www.journals.uchicago.edu/PASP/journal/issues/v117n828/205015/205015.html Powerpoint presentation available @: http://www.wildealien.com/astro/vst.ppt