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Entrepreneurship Support Programs (ESP) in engineering provide education, mentoring, and advising for emerging entrepreneurs and their ventures. The impact of ESPs on engineering students’ professional formation and the acquisition of different attributes—such as creativity, risk-taking, empathy, and curiosity—is largely unknown. Though the social sciences have a strong and robust history of studying many of the attributes, such as creativity and problem-solving, typically associated with entrepreneurship, there has been little connection between this foundational research and the work of ESPs. In fact, two separate systematic reviews have shown that most published work in STEM entrepreneurship education is not theoretically grounded and does not follow standards of quality research approaches in the social sciences. In an effort to bridge the gap between social scientists and engineering entrepreneurship practitioners, the authors are conducting a two-phase study. Phase 1 of the study involves conducting a Delphi study to identify the top entrepreneurial attributes of professionals and researchers who lead ESPs. Phase 2 of the study includes conducting workshops with social scientists who study the attributes and ESP leaders. The goal of the workshops is to identify assessment frameworks grounded in social science theory and literature that will guide the measurement of the attributes. This session will focus on the results of the Delphi phase. Delphi study is a common research technique used to achieve consensus among experts (Hasson, Keeney, and McKenna, 2000). Seventy-three participants who lead or have led an ESP, have conducted research in entrepreneurship education, or act as administrators for relevant entrepreneurship programs were invited to participate in the Delphi study. Of the 73 invited, 14 completed at least two rounds of the Delphi study. All participants were experts in the field of engineering entrepreneurship education. The Delphi Study comprised three rounds- brainstorming, narrowing, and ranking. Each phase of the Delphi asked participants to think about three different sets of attributes: 1) entrepreneurial attributes that they thought were important in the development of an entrepreneur, 2) attributes in becoming a successful professional, and 3) attributes in working in an inclusive workspace. In the brainstorming phase, participants were sent an online questionnaire and were asked to brainstorm as many attributes as they could think of. The results of the brainstorming questionnaire were consolidated and used to develop the narrowing questionnaire, where participants were asked to narrow all attributes to the top 10 key attributes The results from the narrowing questionnaire were then used to develop a ranking questionnaire, where participants were asked to rank the items on a scale of importance with 1 being the most important to 10 being the least important for each set of attributes. The results of the phase 3 questionnaire were analyzed to identify the attributes that were ranked the highest among a majority of the participants. This paper discusses the findings of the Delphi Study and its implications in assessing the impact of ESP on entrepreneur formation.more » « less
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Fundamental Symmetries, Neutrons, and Neutrinos (FSNN): Whitepaper for the 2023 NSAC Long Range PlanWhitepaper for the 2023 NSAC Long Range Planmore » « less
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We report the characteristics of collisional plasma shocks formed during interactions between low density (ne≈1015 cm−3), low temperature (Te≈2 eV), high velocity (30 km s−1), plasma jets and stagnant plasma of similar parameters. This investigation seeks to probe the structure of shocks in multi-ion-species plasmas, in particular, the presence of gradient-driven ion species separation at the shock front. The railgun-accelerated jets utilized here have previously been shown to exist in a collisional regime with intra-jet collisional mean-free-path substantially smaller than jet size [Schneider et al., Plasma Sources Sci. Technol. 29, 045013 (2020)]. To induce collisions, a dielectric barrier is located downstream of the railgun to stagnate an initially supersonic plasma jet. Around the time of stagnation, the railgun emits a second jet which shortly collides with the stagnant plasma. The presence of a structure emitting in the UV-visible band is evident in high-speed photographs of the moments immediately following the arrival of the second jet at the stagnant plasma. Analysis of interferometric and spectroscopic data suggests that the observed increase in density from the jet to the post-collision plasma is consistent with the formation of a bow shock structure with a multi-millimeter-scale ion shock layer.
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Abstract SBND is the near detector of the Short-Baseline Neutrino program at Fermilab. Its location near to the Booster Neutrino Beam source and relatively large mass will allow the study of neutrino interactions on argon with unprecedented statistics. This paper describes the expected performance of the SBND photon detection system, using a simulated sample of beam neutrinos and cosmogenic particles. Its design is a dual readout concept combining a system of 120 photomultiplier tubes, used for triggering, with a system of 192 X-ARAPUCA devices, located behind the anode wire planes. Furthermore, covering the cathode plane with highly-reflective panels coated with a wavelength-shifting compound recovers part of the light emitted towards the cathode, where no optical detectors exist. We show how this new design provides a high light yield and a more uniform detection efficiency, an excellent timing resolution and an independent 3D-position reconstruction using only the scintillation light. Finally, the whole reconstruction chain is applied to recover the temporal structure of the beam spill, which is resolved with a resolution on the order of nanoseconds.
Free, publicly-accessible full text available October 1, 2025 -
Noble element time projection chambers are a leading technology for rare event detection in physics, such as for dark matter and neutrinoless double beta decay searches. Time projection chambers typically assign event position in the drift direction using the relative timing of prompt scintillation and delayed charge collection signals, allowing for reconstruction of an absolute position in the drift direction. In this paper, alternate methods for assigning event drift distance via quantification of electron diffusion in a pure high pressure xenon gas time projection chamber are explored. Data from the NEXT-White detector demonstrate the ability to achieve good position assignment accuracy for both high- and low-energy events. Using point-like energy deposits frommore » « less
Kr calibration electron captures ($$^{83\textrm{m}}$$ keV), the position of origin of low-energy events is determined to 2 cm precision with bias$$E\sim 45$$ mm. A convolutional neural network approach is then used to quantify diffusion for longer tracks ($$< 1~$$ MeV), from radiogenic electrons, yielding a precision of 3 cm on the event barycenter. The precision achieved with these methods indicates the feasibility energy calibrations of better than 1% FWHM at Q$$E\ge ~1.5$$ in pure xenon, as well as the potential for event fiducialization in large future detectors using an alternate method that does not rely on primary scintillation.$$_{\beta \beta }$$ Free, publicly-accessible full text available May 1, 2025 -
Context. The nearby elliptical galaxy M87 contains one of only two supermassive black holes whose emission surrounding the event horizon has been imaged by the Event Horizon Telescope (EHT). In 2018, more than two dozen multi-wavelength (MWL) facilities (from radio toγ -ray energies) took part in the second M87 EHT campaign.Aims. The goal of this extensive MWL campaign was to better understand the physics of the accreting black hole M87*, the relationship between the inflow and inner jets, and the high-energy particle acceleration. Understanding the complex astrophysics is also a necessary first step towards performing further tests of general relativity.Methods. The MWL campaign took place in April 2018, overlapping with the EHT M87* observations. We present a new, contemporaneous spectral energy distribution (SED) ranging from radio to very high-energy (VHE)γ -rays as well as details of the individual observations and light curves. We also conducted phenomenological modelling to investigate the basic source properties.Results. We present the first VHEγ -ray flare from M87 detected since 2010. The flux above 350 GeV more than doubled within a period of ≈36 hours. We find that the X-ray flux is enhanced by about a factor of two compared to 2017, while the radio and millimetre core fluxes are consistent between 2017 and 2018. We detect evidence for a monotonically increasing jet position angle that corresponds to variations in the bright spot of the EHT image.Conclusions. Our results show the value of continued MWL monitoring together with precision imaging for addressing the origins of high-energy particle acceleration. While we cannot currently pinpoint the precise location where such acceleration takes place, the new VHEγ -ray flare already presents a challenge to simple one-zone leptonic emission model approaches, and it emphasises the need for combined image and spectral modelling.Free, publicly-accessible full text available December 1, 2025 -
Abstract The Breakthrough Listen Initiative is conducting a program using multiple telescopes around the world to search for “technosignatures”: artificial transmitters of extraterrestrial origin from beyond our solar system. The Very Energetic Radiation Imaging Telescope Array System (VERITAS) Collaboration joined this program in 2018 and provides the capability to search for one particular technosignature: optical pulses of a few nanoseconds in duration detectable over interstellar distances. We report here on the analysis and results of dedicated VERITAS observations of Breakthrough Listen targets conducted in 2019 and 2020 and of archival VERITAS data collected since 2012. Thirty hours of dedicated observations of 136 targets and 249 archival observations of 140 targets were analyzed and did not reveal any signals consistent with a technosignature. The results are used to place limits on the fraction of stars hosting transmitting civilizations. We also discuss the minimum pulse sensitivity of our observations and present VERITAS observations of CALIOP: a space-based pulsed laser on board the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations. The detection of these pulses with VERITAS, using the analysis techniques developed for our technosignature search, allows a test of our analysis efficiency and serves as an important proof of principle.