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Racial and ethnic disparities in STEM achievement are associated with weaker economic growth, greater social inequalities, and narrower parameters of scientific inquiry. Extant research suggests that undergraduate research experiences (URE) can reduce those disparities by enhancing perceptions of belonging and scientific self-efficacy among students from underrepresented groups. However, to date, very few studies have examined the relationship between URE and post-baccalaureate educational achievement gains among such students and those that have tend to be limited in terms of causal leverage and generalizability. In this study, we aim to make progress by analyzing data from the California State University system’s longstanding Louis Stokes Alliance for Minority Participation (CSU-LSAMP) program. Applying a quasi-experimental research design and drawing upon a large and representative sample of students whom we tracked over time, we observe that URE is strongly associated with post-baccalaureate enrollment and graduation in STEM disciplines among students from underrepresented backgrounds. 

Small, highly absorbing points are randomly present on the surfaces of the main interferometer optics in Advanced LIGO. The resulting nanometer scale thermo-elastic deformations and substrate lenses from these micron-scale absorbers significantly reduce the sensitivity of the interferometer directly though a reduction in the power-recycling gain and indirect interactions with the feedback control system. We review the expected surface deformation from point absorbers and provide a pedagogical description of the impact on power buildup in second generation gravitational wave detectors (dual-recycled Fabry–Perot Michelson interferometers). This analysis predicts that the power-dependent reduction in interferometer performance will significantly degrade maximum stored power by up to 50% and, hence, limit GW sensitivity, but it suggests system wide corrections that can be implemented in current and future GW detectors. This is particularly pressing given that future GW detectors call for an order of magnitude more stored power than currently used in Advanced LIGO in Observing Run 3. We briefly review strategies to mitigate the effects of point absorbers in current and future GW wave detectors to maximize the success of these enterprises.