2019 Summer Undergraduate Research Program (SURP) Symposium
Presentation Type
Open Access Poster Presentation
Keywords
Cepheids; Fourier analysis;
Abstract
Cepheid stars are valuable due to their usefulness in determining distances within our galaxy, and to other galaxies. Cepheid stars’ light variation can be parameterized using a Fourier series with coefficients Ai and ��i . Fourier coefficients have been shown to have trends linked to physical characteristics of Cepheids and RR Lyrae stars, such as luminosity, radius, pulsation modes and metallicity. Using data from the OGLE III and IV surveys, we determined relationships between Fourier coefficients in different photometric system and observed the influence of metallicity on the Cepheids in the Small Magellanic Cloud and the Large Magellanic Cloud. The results obtained for each galaxy will be compared with each other and with data from prior studies to provide a more complete overall picture of trends observed in the Fourier coefficients for Cepheids.
Start Date
2-8-2019 11:30 AM
End Date
2-8-2019 1:30 PM
Event Host
Summer Undergraduate Research Program, University of Northern Iowa
Faculty Advisor
Siobahn Morgan
Department
Department of Earth and Environmental Sciences
Copyright
©2019 Forrest Cronin and Siobahn Morgan
File Format
application/pdf
Recommended Citation
Cronin, Forrest and Morgan, Siobahn, "Investigating Fourier Coefficient Relationships of Cepheid Variable Stars" (2019). Summer Undergraduate Research Program (SURP) Symposium. 23.
https://scholarworks.uni.edu/surp/2019/all/23
Investigating Fourier Coefficient Relationships of Cepheid Variable Stars
Cepheid stars are valuable due to their usefulness in determining distances within our galaxy, and to other galaxies. Cepheid stars’ light variation can be parameterized using a Fourier series with coefficients Ai and ��i . Fourier coefficients have been shown to have trends linked to physical characteristics of Cepheids and RR Lyrae stars, such as luminosity, radius, pulsation modes and metallicity. Using data from the OGLE III and IV surveys, we determined relationships between Fourier coefficients in different photometric system and observed the influence of metallicity on the Cepheids in the Small Magellanic Cloud and the Large Magellanic Cloud. The results obtained for each galaxy will be compared with each other and with data from prior studies to provide a more complete overall picture of trends observed in the Fourier coefficients for Cepheids.
