Cluster Membership of White Dwarfs in M35

Document Type


Degree Name

Master of Science (MS)



Date of Award

Summer 2017


White dwarf stars, the remains of low-and -intermediate-mass stars that have finished their evolution, have been known to exist for over a century, yet new discoveries continually uncover new mysteries surrounding these stars. Recently a new class of white dwarf was discovered. This new class is characterized by its carbon-dominated atmosphere and thus brings up many questions about its formation. To shed light on this mystery, as well as to better constrain the relationship between stellar masses and their remnant white dwarf masses, we seek to determine the membership of white dwarfs in the field of the open cluster NGC 2168 (M35). Cluster membership is deduced by calculating the stars’ proper motions. If the white dwarfs share the same proper motion as known cluster stars, then they are likely cluster members and stringent constraints can be placed on possible formation scenarios. Although white dwarf membership to M35 was not determined in this work due to data quality issues, the distance to M35 was calculated using the Gaia mission’s parallax measurements. This resulted in a distance of which is the first trigonometric parallax determination for M35 and the most precise distance to the cluster to date.


Kurtis A Williams

Subject Categories

Astrophysics and Astronomy | Physical Sciences and Mathematics | Physics