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Researchers have been aggressively investigating group-IV (Ge, SiGeSn, GeSn) optoelectronic materials to realize tunable wavelength lasers, photodetectors, and transistors. By exploiting strain and bandgap engineering of these materials via choice of substrate orientation and intelligent buffer engineering as well as precise control of Sn alloy composition during material synthesis, it will offer widespread device applications. There is an opportunity to improve the device-level quality of GeSn material systems along with higher Sn incorporation that face growth challenges during epitaxy. The current research work presents the substrate orientation and misorientation (100)/2˚, (100)/6˚, (110), (111) mediated epitaxial GeSn and Ge optoelectronic materials synthesized via MBE and analyzed using several analytical tools. X-ray analysis demonstrated high quality GeSn materials with less broadening and good symmetricity on (100) compared to (110) GeSn materials. Minority carrier lifetimes of these GeSn epilayers were extracted as > 400 ns for the (100) substrate misoriented by 6˚ towards [110] direction. Raman spectroscopy measurements were performed to study the vibrational properties, where the LO phonon wavenumber shifts at ωLO = 301.11 ± 0.8 cm¬–1 from (100)/2˚, (100)/6˚ and (110) oriented GeSn epilayers that were synthesized in equivalent growth conditions. Cross-sectional TEM of (100)/2˚ GeSn sample was performed that revealed good quality GeSn material on GaAs. Elimination of the interfaced electronic dipole charge effects, that destabilize the group-IV/group III-V heterointerface and further layer growths, is attributed to aid in achieving superior quality GeSn epitaxial materials over a (100) substrate that is misoriented by 6˚ towards the [110] direction. This substrate offcut will enable to annihilate antiphase domains due to polar-on-non-polar epitaxial growth, which further reduce non-radiative recombination centers in GeSn material. Hence, growth of GeSn material on misoriented (100) substrate offers two-fold benefits: (i) reduced active defects at the GeSn/III-V heterointerface, and (ii) self-annihilation of the antiphase domain boundaries for enhancing the efficiency of optical devices. 

The student body in university science classrooms is increasingly diverse demographically and this change brings with it an increased chance of mismatch between professor’s expectations and students’ behaviors. Being aware of how cultural expectations influence teaching and learning is the first step in understanding and overcoming these mismatches in order to help all students succeed. This involves making expectations clear, particularly about homework requirements (Ludwig et al., 2011), and defining the line between collaboration and cheating (Craig et al., 2010). When possible, professors should be flexible regarding different cultures’ ideas of time (Hall, 1983), family obligations (Hoover, 2017), and the social power structure (Hofstede, 1986; Yoo, 2014). At the same time, professors should maintain high expectations of all students regardless of ethnic background (Rosenthal & Jacobson, 1968). Drawing from published research as well as interview and survey data, we highlight ways for both professors and students to create an atmosphere of belonging (Walton & Cohen, 2011) and an appreciation of people from all cultures (Museus et al., 2017). 

This Research Work-in-Progress paper builds on previous literature related to the professional formation of engineers and issues pertaining to diversity and inclusion within engineering though a comparative analysis of two different disciplines. These issues are complex, interrelated and challenging to untangle, and thus require innovative strategies to explore them. Our larger study utilizes design thinking with an embedded mixed-methods research approach to investigate foundational understandings of professional formation and diversity and inclusion in engineering. Herein, we describe preliminary findings from co-design sessions we conducted in Biomedical Engineering (BME) and Electrical and Computer Engineering (ECE) at Purdue University. We compare the design solutions generated by stakeholders and discuss insights regarding the unique contexts and needs of each program, as well as the impacts of the different activities and contexts of the design sessions themselves. 

The lack of diversity and inclusion has been a major challenge affecting engineering programs all over the United States. This problem has been persistent over the years and has been difficult to address despite considerable amount of attention, enriched conversations, and money that has been put towards addressing it. One of the reasons behind this lack of diversity could be the presence of exclusionary behaviors, such as bias and discrimination that permeate the culture of engineering. To address this “wicked” problem, a deeper understanding of current culture and of potential change strategies toward integrating inclusion and diversity is necessary. Our larger NSF funded research project seeks to achieve this understanding through design thinking. While design thinking has been documented to successfully achieve desired outcomes for numerous other problems, its effectiveness as a tool to understand and solve the “wicked problem” of transformation of disciplinary culture related to diversity and inclusion in engineering is not yet known. This Work-in-Progress paper will address the effectiveness of using a design thinking approach by answering the research question: How did stakeholder participants perceive the impact of design sessions on their understanding and value of diversity and inclusion in the professional formation of biomedical engineers? To address this research question, our research team is coordinating six design sessions within each of two engineering schools: Electrical and Computer Engineering (ECE) and Biomedical Engineering (BME) at a large Midwest University. Currently, we have completed the initial phases of the design sessions in the BME school, and hence this paper focuses on insights from preliminary data analysis of BME Design sessions. BME design sessions were conducted with 15 key stakeholders from the program including students, faculty, staff and administrators. Each of the six design session was two hours long. The research team facilitated the inspiration and ideation phase of the design thinking process throughout. Facilitation involved providing prompts and activities to guide the stakeholders through the design thinking processes of problem identification, problem scoping, and prototype solution generation related to diversity and inclusion within the school culture. A mixed-methods approach involving both qualitative and quantitative data analysis is being used to evaluate the efficacy of design thinking as a tool to address diversity and inclusion in professional formation of engineers. Artifacts such as journey maps, culture maps, and design notebooks generated by our stakeholders throughout the design sessions will be qualitatively analyzed to evaluate the role and effectiveness of design thinking in shaping a more diverse and inclusive culture within BME and, eventually ECE. Following the design sessions, participants were interviewed one-on-one to understand how their thoughts about diversity and inclusion in professional formation of biomedical engineers may have changed, and to gather participants’ self-assessment of the design process. Coupled with the interviews, an online survey was administered to assess the participants’ ranking of the solutions generated at the conclusion design sessions in terms of their novelty, importance and feasibility for implementation within their school. This Work-in-Progress paper will discuss relevant findings from initial quantitative analyses of the data collected from the post-design session surveys and is an interim report evaluating participants’ perceptions of the impact of these design sessions on their understanding of diversity and inclusion in professional formation of biomedical engineers. 

This project explores how engineering students understand diversity and inclusion within their engineering programs, and how these understandings are shaped by aspects of the environment in which they are situated. Our study is a component of a broader research project that is examining the seemingly intractable problems of diversity and inclusion that emerge through the converging threads of formation of professional identity and culture of engineering disciplines. In this study we utilized a qualitative analysis of interview data to explore the undergraduate students’ perceptions of diversity and inclusion within the School of Electrical and Computer Engineering (ECE) at Purdue University [1]. Our interview draws upon cultural dimensions of engineering disciplines that encourage student to reflect upon and assess diversity and inclusion efforts within ECE [2]. To interrogate students’ perceptions of diversity and inclusion, we interviewed 13 current or past undergraduate ECE students. With nearly 40 percent of the undergraduate ECE students identifying as international students, such a significant international population poses tremendous learning opportunities as well as challenges related to diversity and inclusion. Thus, formal efforts within ECE have been made to bridge cultural differences, develop intercultural competencies, and promote inclusion of internationally and domestically diverse ECE members. However, these efforts have met with mixed results. Our analysis of the interview data suggests that these efforts often were not aligned with literature about how to successfully bridge culture differences in that they lacked an explicit focus on students’ understandings of diversity and inclusion, nor did they provide opportunities for students to reflect on their personal and educational experiences. In what follows, we first examine the framing of scholarship about diversity and inclusion within engineering and then draw upon literature using Kolb’s experiential learning models to illuminate the transformational nature that reflection plays within establishing ways of viewing complex social problems. With this combination and reimagining of reflection as a pathway to more deeply understanding diversity and inclusion, we describe our research methods, data analysis, and the findings from our qualitative analysis. Finally, we conclude with a discussion of the tensions pertaining to difference and sameness that emerged through our analysis. Namely, formal efforts within ECE required both scaffolding and intentionality. Without proper facilitation, the central role that diversity and inclusion plays within professional formation appeared forced, created more cultural isolation, or students ignored these efforts altogether to complete assignments. We conclude by offering both theoretical and pragmatic implications for engineering curriculum. 

This report presents a comprehensive collection of searches for new physics performed by the ATLAS Collaboration during the Run~2 period of data taking at the Large Hadron Collider, from 2015 to 2018, corresponding to about 140~$$^{-1}$$ of $$\sqrt{s}=13$$~TeV proton--proton collision data. These searches cover a variety of beyond-the-standard model topics such as dark matter candidates, new vector bosons, hidden-sector particles, leptoquarks, or vector-like quarks, among others. Searches for supersymmetric particles or extended Higgs sectors are explicitly excluded as these are the subject of separate reports by the Collaboration. For each topic, the most relevant searches are described, focusing on their importance and sensitivity and, when appropriate, highlighting the experimental techniques employed. In addition to the description of each analysis, complementary searches are compared, and the overall sensitivity of the ATLAS experiment to each type of new physics is discussed. Summary plots and statistical combinations of multiple searches are included whenever possible. 

A<sc>bstract</sc> A study of the Higgs boson decaying into bottom quarks (H→$$ b\overline{b} $$ $b\overline{b}$) and charm quarks (H→$$ c\overline{c} $$ $c\overline{c}$) is performed, in the associated production channel of the Higgs boson with aWorZboson, using 140 fb⁻¹of proton-proton collision data at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV collected by the ATLAS detector. The individual production ofWHandZHwithH→$$ b\overline{b} $$ $b\overline{b}$is established with observed (expected) significances of 5.3 (5.5) and 4.9 (5.6) standard deviations, respectively. Differential cross-section measurements of the gauge boson transverse momentum within the simplified template cross-section framework are performed in a total of 13 kinematical fiducial regions. The search for theH→$$ c\overline{c} $$ $c\overline{c}$decay yields an observed (expected) upper limit at 95% confidence level of 11.5 (10.6) times the Standard Model prediction. The results are also used to set constraints on the charm coupling modifier, resulting in|κ_c| <4.2 at 95% confidence level. Combining theH→$$ b\overline{b} $$ $b\overline{b}$andH→$$ c\overline{c} $$ $c\overline{c}$measurements constrains the absolute value of the ratio of Higgs-charm and Higgs-bottom coupling modifiers (|κ_c/κ_b|) to be less than 3.6 at 95% confidence level. 

The ATLAS experiment has developed extensive software and distributed computing systems for Run 3 of the LHC. These systems are described in detail, including software infrastructure and workflows, distributed data and workload management, database infrastructure, and validation. The use of these systems to prepare the data for physics analysis and assess its quality are described, along with the software tools used for data analysis itself. An outlook for the development of these projects towards Run 4 is also provided. 

A<sc>bstract</sc> Differential measurements of Higgs boson production in theτ-lepton-pair decay channel are presented in the gluon fusion, vector-boson fusion (VBF),VHand$$ t\overline{t}H $$ $t\overline{t}H$associated production modes, with particular focus on the VBF production mode. The data used to perform the measurements correspond to 140 fb⁻¹of proton-proton collisions collected by the ATLAS experiment at the LHC. Two methods are used to perform the measurements: theSimplified Template Cross-Section(STXS) approach and anUnfolded Fiducial Differentialmeasurement considering only the VBF phase space. For the STXS measurement, events are categorized by their production mode and kinematic properties such as the Higgs boson’s transverse momentum ($$ {p}_{\textrm{T}}^{\textrm{H}} $$ $p_T^H$), the number of jets produced in association with the Higgs boson, or the invariant mass of the two leading jets (m_jj). For the VBF production mode, the ratio of the measured cross-section to the Standard Model prediction form_jj> 1.5 TeV and$$ {p}_{\textrm{T}}^{\textrm{H}} $$ $p_T^H$> 200 GeV ($$ {p}_{\textrm{T}}^{\textrm{H}} $$ $p_T^H$< 200 GeV) is$$ {1.29}_{-0.34}^{+0.39} $$ ${1.29}_{-0.34}^{+0.39}$($$ {0.12}_{-0.33}^{+0.34} $$ ${0.12}_{-0.33}^{+0.34}$). This is the first VBF measurement for the higher-$$ {p}_{\textrm{T}}^{\textrm{H}} $$ $p_T^H$criteria, and the most precise for the lower-$$ {p}_{\textrm{T}}^{\textrm{H}} $$ $p_T^H$criteria. Thefiducialcross-section measurements, which only consider the kinematic properties of the event, are performed as functions of variables characterizing the VBF topology, such as the signed ∆ϕ_jjbetween the two leading jets. The measurements have a precision of 30%–50% and agree well with the Standard Model predictions. These results are interpreted in the SMEFT framework, and place the strongest constraints to date on the CP-odd Wilson coefficient$$ {c}_{H\overset{\sim }{W}} $$ $c_{H\tilde{W}}$. 

A search is performed for dark matter particles produced in association with a resonantly produced pair of b-quarks with 30 < mbb < 150 GeV using 140 fb−1 of proton-proton collisions at a center-of-mass energy of 13 TeV recorded by the ATLAS detector at the LHC. This signature is expected in extensions of the standard model predicting the production of dark matter particles, in particular those containing a dark Higgs boson s that decays into bb¯. The highly boosted s → bb¯ topology is reconstructed using jet reclustering and a new identification algorithm. This search places stringent constraints across regions of the dark Higgs model parameter space that satisfy the observed relic density, excluding dark Higgs bosons with masses between 30 and 150 GeV in benchmark scenarios with Z0 mediator masses up to 4.8 TeV at 95% confidence level.