  Studies on physics identity have shown that it is one of the main factors
that can predict a person's persistence in the field; therefore, studying
physics identity is critical to increase diversity within the field of physics
and to understand what changes can allow more women and minorities to identify
with the field. In this study, we investigate informal physics programs as
spaces for physics identity exploration. These programs provide unique
conditions under which to study physics identity development along with other
identities. Informal physics spaces allow for voluntary engagement, as well as
elements of agency and autonomy within the exploration of physics. Thus these
spaces allow an identity to form outside of the constraints traditionally found
in academic settings. In this work, we operationalized the Community of
Practice (CoP) framework to study the development of physics identities within
university students who facilitate informal physics programs. We present the
stories from two physics graduate students out of our sample to provide a
context for testing the feasibility of the extended framework and to identify
how experiences within an informal physics program can shape physics identity
development. This paper presents the operationalized constructs within the
Community of Practice framework, how these constructs are applied to the
narrated experiences of our participants, and highlights how we can use this
framework to understand the nuances of physics identity development as well as
the factors that can influence that development.
