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Abstract While binary merger events have been an active area of study in both simulations and observational work, the formation channels by which a high-mass star extends from Roche lobe overflow (RLO) in a decaying orbit of a black-hole (BH) companion to a binary black-hole (BBH) system merits further investigation. Variable length-scales must be employed to accurately represent the dynamical fluid transfer and morphological development of the primary star as it conforms to a diminishing Roche lobe under the runaway influence of the proximal BH. We have simulated and evolved binary mass flow under these conditions to better identify the key transitional processes from RLO to BBHs. We demonstrate a new methodology to model RLO systems to unprecedented resolution simultaneously across the envelope, donor wind, tidal stream, and accretion disk regimes without reliance upon previously universal symmetry, mass flux, and angular momentum flux assumptions. We have applied this method to the semidetached high-mass X-ray binary M33 X-7 in order to provide a direct comparison to recent observations of an RLO candidate system at two overflow states of overfilling factorsf= 1.01 andf= 1.1. We found extreme overflow (f= 1.1) to be entirely conservative in both mass and angular momentum transport, forming a conical L1 tidal stream of density and deflected angle comparable to existing predictions. This case lies within the unstable mass transfer (MT) regime as recently proposed of M33 X-7. Thef= 1.01 case differed in stream geometry, accretion disk size, and efficiency, demonstrating nonconservative stable MT through a ballistic uniform-width stream. The nonconservative and stable nature of thef= 1.01 case MT also suggests that existing assumptions of semidetached binaries undergoing RLO may mischaracterize their role and distribution as progenitors of BBHs and common envelopes. 

The environment, science, technology, engineering, arts, and mathematics fields (a collection of fields we call E-STEAM) continue to grow and remain economically and ecologically important. However, historically excluded groups remain underrepresented in science and technology professions, particularly in environmental and digital media fields. Consequently, building pathways for historically excluded students to enter economically viable and ecologically influential E-STEAM professions is critically important. These new pathways hold promise for increasing innovation within these fields and ensuring a multiplicity of representation as these fields are shaped and reshaped to attend to the plural interests of diverse communities. Consequently, this conceptual paper describes an eco-digital storytelling (EDS) approach to engaging historically excluded populations in science, technology, engineering, and mathematics (STEM). This approach offers structured learning opportunities connected to learner interests and community needs with the aim of increasing E-STEAM identity and career interest of teens from groups historically excluded from E-STEAM fields. E-STEAM identity is a meaning one can attach to oneself or that can be ascribed externally by others as individuals interact and engage in E-STEAM fields in ways that foreground the environment. The EDS approach leverages community-based action, technology and digital media, and arts and storytelling as entry points for engaging learners. EDS is designed to increase teens’ content knowledge within multiple E-STEAM fields and to provide numerous technology-rich experiences in both application of geospatial technologies (i.e., GPS, interactive maps) and digital media creation (i.e., video, animation, ArcGIS StoryMaps) as a way to shape teens’ cultural learning pathways. Examples of rich digital media presentations developed to communicate the EDS approach and local environmental opportunities, challenges, and projects are provided that exemplify how both participation in and communication of environmental action can contribute to more promising and sustainable futures.