Abstract by Rochelle Biancardi
Physics and Astronomy
J. Ward Moody
Photometrically Measuring Redshift and Equivalent Width of Dwarf Galaxies
One of the biggest challenges in astronomy is measuring the distance to celestial objects, especially galaxies. Unfortunately, there is no tape measure long enough to measure the distance to the Andromeda Galaxy (although I’m sure Elon Musk is working on that). The redshift of galaxies (how much the light has been stretched by the expansion of the universe) is a good indicator of how far away they are. But the best way to measure redshift is spectroscopically, which is very time consuming and requires large telescopes. My research is working to develop a simpler method to calculate the distance to (relatively) nearby galaxies. I use three narrow Hα filters, adjusted for different redshifts, to calculate the distance to these galaxies photometrically. I am currently developing a relationship between the ratios of these three filters and the redshift of these galaxies as well as the equivalent width of their Hα emission lines. Once a relationship has been well-established, this method could be used for any nearby galaxy with an H-alpha emission line (a common trait among galaxies).