  In undergraduate research experiences, student development of an identity as
a scientist is coupled to their sense of ownership of their research projects.
As a a first step towards studying similar connections in physics laboratory
courses, we investigate student ownership of projects in a lasers-based
upper-division course. Students spent the final seven weeks of the semester
working in groups on final projects of their choosing. Using data from the
Project Ownership Survey and weekly student reflections, we investigate student
ownership as it relates to students' personal agency, self-efficacy, peer
interactions, and complex affective responses to challenges and successes. We
present evidence of students' project ownership in an upper-division physics
lab. Additionally, we find that there is a complex relationship between student
affect and their sense of ownership.
