White Dwarf Stars and the Age of the Milky Way

White Dwarf Stars and the Age of the Milky Way Researchers: Alisa Tiselska, Theodore von Hippel, Allison Woodruff, and Joey Hamill Faculty mentor: Theodore Von Hippel Abstract Author: Alisa Tiselska Our research objective is to determine the ages of the Milky Way’s stellar populations using our derived ages from thousands of white dwarf stars. Right ascension, declination, parallax, and proper motion values for known white dwarfs were taken from the Gaia Observatory database to calculate U, V, and W velocities relative to our position in the Galaxy. We wrote two codes —one in Matlab and one in Python — to assist with error propagation. Assuming that the input error distributions are Gaussian and that the transformations from the astrometric data to the U, V, and W velocities are sufficiently linear, we calculated the probability that each star belongs to the Galactic thin disk, thick disk, or halo. We are currently working on determining the ages of these star populations. The halo stars are the oldest of the three types; therefore, the average age of this population could give us an accurate estimate of the Milky Way’s age