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The Quantum for All project is designed to expand Quantum Information Science education in precollege education. The professional development model includes an opportunity for teachers to learn QIS and then teach a summer camp. In this presentation, we will examine growth in student knowledge and confidence in the QIS, as well as attitudes the students have around the topics and careers in QIS. We will also correlate these findings with teacher content knowledge and confidence for the various topics, since some topics were initially unfamiliar to the teachers.more » « less
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The Quantum for All project has developed instructional materials and a professional development program to expand Quantum Information Science education in precollege education. In this paper, we discuss the background for Quantum Science education in the United States. We then discuss the design of the professional development plan and the development of the materials by the Leadership Team, and the workshops for teachers to learn and utilize this content. We will examine growth in teacher knowledge and confidence and examine the variation of these things across content domains as represented by the instructional modules.more » « less
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The adoption of innovations in science education into classroom instruction always presents a challenge, particularly if the innovation involves content that is unfamiliar to the teacher. Teachers need adequate instructional materials and supplies as well as professional development on their use in the classroom. Quantum information science (QIS) is a rapidly developing field that has significant implications across many areas, not just science. The US National Science Foundation funded a project to meet the challenge of providing teachers the resources and support they need to take QIS into high school classrooms. We will discuss the professional development model developed by our project and report on the effect on classroom implementation by teachers who have participated in the program. The major innovation in our model for professional development is that the teacher professional development is tied to summer camp experience for students during which the teachers can test their delivery of the material with students in the summer camp. We will report on the growth of teacher and student knowledge around QIS topics based of data collected during the teacher workshop and the subsequent summer camp. We will also present evidence that the summer camp was an important factor for the teachers when considering if and how to use the QIS materials in their regular classroomsmore » « less
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Quantum information science (QIS) is critical to the future of economic and national security, commerce, and technology). There is a broad need to develop a "quantum smart" workforce with some on critical topics, such as quantum concepts that are relevant to everyday experiences in information security, smart phones, computers, and other widely used technology. The Quantum for All project, funded by the US National Science Foundation, provides opportunities for students to learn about various aspects of quantum science by providing professional development for STEM educators to learn and practice QIS. We utilize a trainer of trainer approach. In this paper we will discuss the content areas and provide an outline of the professional development model. We will also examine growth in teacher content knowledge and their confidence in that content knowledge. Our preliminary results are that the workshops are effective in raising both metrics as measured by pre- and post-surveys, however, there are differences between the content areas. We will examine these differences and provide possible reasons for the resultsmore » « less
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ABSTRACT AimTropical peatlands are globally significant carbon stores, increasingly threatened by human activities and climate change. However, their ecohydrological responses to shifting water availability remain poorly understood. In this study, we investigate the connections between climate change, hydrology and vegetation dynamics in a coastal tropical peatland in Panama, aiming to understand the effects of future drying on peatland dynamics. LocationBocas del Toro, Panama (9°22′54″N, 82°21′59″W). TaxonAngiosperms. MethodsHigh‐resolution multiproxy palaeoecological data, including pollen and plant macrofossils (vegetation), testate amoebae (water‐table depth) and physical peat properties, are used to explore the relationships between climate change, hydrology and vegetation in a coastal tropical peatland over the past 700 years. Downscaled climate simulations are integrated with this process‐based understanding to project the likely future responses of this coastal peatland to climate change. ResultsWe identify a clear connection between precipitation variability, driven by shifts in the Intertropical Convergence Zone and water‐table dynamics, which subsequently influence changes in the peatland vegetation mosaic. Historical drier periods are marked by the expansion of shrub communities into the open peatland plain. Main ConclusionsPalaeoecological studies incorporating climate and hydrological proxies are essential for understanding both recent and future ecohydrological dynamics of tropical peatlands. Our findings suggest that in response to future climate change, water tables will lower and shrub communities will expand due to rising temperatures and reduced precipitation. Additionally, future sea‐level rise, combined with declining rainfall, may result in seawater intrusion and significant vegetation shifts in coastal tropical peatlands.more » « less
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This paper reflects upon the challenges of teacher pro- fessional development, designed primarily for high school physics teachers, where both content and format were unfa- miliar. The content focus was quantum information science (QIS), and the original face-to-face (F2F) environment shifted to an online virtual with only a few months of plan- ning. As a result of C-19, many states are now implementing changes to K–12 education such as virtual options for cours- es or some type of hybrid learning environment.4 Therefore, identifying and addressing the challenges faced in providing virtual professional development may be of use to other ed- ucators who need to incorporate similar elements in virtual environments.more » « less
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Laboratory experimentation is a key component of the development of professional engineers. However, experiments conducted in chemical engineering laboratory classes are commonly more prescriptive than the problems faced by practicing engineers, who have agency to make consequential decisions across the experiment and communication of results. Thus, understanding how experiments in laboratory courses vary in offering students opportunities to make such decisions, and how students navigate higher agency learning experiences is important for preparing graduates ready to direct these practices. In this study, we sought to answer the following research question: What factors are measured by the Consequential Agency in Laboratory Experiments survey? To better understand student perceptions of their agency in relation to laboratory experiments, developed an initial version of the Consequential Agency in Laboratory Experiments survey, following research-based survey development guidelines. We implemented it in six upper-division laboratory courses across two universities. We used exploratory factor analysis to investigate the validity of the data from the survey for measuring relevant constructs of authenticity, agency in specific domains, responsibility, and opportunity to make decisions. We found strong support for items measuring agency as responsibility, authenticity, agency in the communication domain, agency in the experimental design domain, and opportunity to make decisions. These findings provide a foundation for developing a more precise survey capable of measuring agency across various laboratory experiment practices. Such a survey will enable future studies that investigate the impacts of increasing agency in just one domain versus in several. In turn, this can aid faculty in developing higher agency learning experiences that are more feasible to implement, compared to authentic research experiences.more » « less
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Context.Since 2019, GRAVITY has provided direct observations of giant planets and brown dwarfs at separations of down to 95 mas from the host star. Some of these observations have provided the first direct confirmation of companions previously detected by indirect techniques (astrometry and radial velocities). Aims.We want to improve the observing strategy and data reduction in order to lower the inner working angle of GRAVITY in dual-field on-axis mode. We also want to determine the current limitations of the instrument when observing faint companions with separations in the 30–150 mas range. Methods.To improve the inner working angle, we propose a fiber off-pointing strategy during the observations to maximize the ratio of companion-light-to-star-light coupling in the science fiber. We also tested a lower-order model for speckles to decouple the companion light from the star light. We then evaluated the detection limits of GRAVITY using planet injection and retrieval in representative archival data. We compare our results to theoretical expectations. Results.We validate our observing and data-reduction strategy with on-sky observations; first in the context of brown dwarf follow-up on the auxiliary telescopes with HD 984 B, and second with the first confirmation of a substellar candidate around the starGaiaDR3 2728129004119806464. With synthetic companion injection, we demonstrate that the instrument can detect companions down to a contrast of 8 × 10−4(ΔΚ= 7.7 mag) at a separation of 35 mas, and a contrast of 3 × 10−5(ΔΚ= 11 mag) at 100 mas from a bright primary (K< 6.5), for 30 min exposure time. Conclusions.With its inner working angle and astrometric precision, GRAVITY has a unique reach in direct observation parameter space. This study demonstrates the promising synergies between GRAVITY andGaiafor the confirmation and characterization of substellar companions.more » « less
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Abstract Multi-pulsed GRB 190530A, detected by the GBM and LAT onboard Fermi, is the sixth most fluent GBM burst detected so far. This paper presents the timing, spectral, and polarimetric analysis of the prompt emission observed using AstroSat and Fermi to provide insight into the prompt emission radiation mechanisms. The time-integrated spectrum shows conclusive proof of two breaks due to peak energy and a second lower energy break. Time-integrated (55.43 ± 21.30 %) as well as time-resolved polarization measurements, made by the Cadmium Zinc Telluride Imager (CZTI) onboard AstroSat, show a hint of high degree of polarization. The presence of a hint of high degree of polarization and the values of low energy spectral index (αpt) do not run over the synchrotron limit for the first two pulses, supporting the synchrotron origin in an ordered magnetic field. However, during the third pulse, αpt exceeds the synchrotron line of death in few bins, and a thermal signature along with the synchrotron component in the time-resolved spectra is observed. Furthermore, we also report the earliest optical observations constraining afterglow polarization using the MASTER (P < 1.3 %) and the redshift measurement (z= 0.9386) obtained with the 10.4m GTC telescopes. The broadband afterglow can be described with a forward shock model for an ISM-like medium with a wide jet opening angle. We determine a circumburst density of n0 ∼ 7.41, kinetic energy EK ∼ 7.24 × 1054 erg, and radiated γ-ray energy Eγ, iso ∼ 6.05 × 1054 erg, respectively.more » « less
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Aims. HD 206893 is a nearby debris disk star that hosts a previously identified brown dwarf companion with an orbital separation of ∼10 au. Long-term precise radial velocity (RV) monitoring, as well as anomalies in the system proper motion, has suggested the presence of an additional, inner companion in the system. Methods. Using information from ongoing precision RV measurements with the HARPS spectrograph, as well as Gaia host star astrometry, we have undertaken a multi-epoch search for the purported additional planet using the VLTI/GRAVITY instrument. Results. We report a high-significance detection over three epochs of the companion HD 206893c, which shows clear evidence for Keplerian orbital motion. Our astrometry with ∼50−100 μarcsec precision afforded by GRAVITY allows us to derive a dynamical mass of 12.7$$ ^{+1.2}_{-1.0} $$ M Jup and an orbital separation of 3.53$$ ^{+0.08}_{-0.06} $$ au for HD 206893c. Our fits to the orbits of both companions in the system use both Gaia astrometry and RVs to also provide a precise dynamical estimate of the previously uncertain mass of the B component, and therefore allow us to derive an age of 155 ± 15 Myr for the system. We find that theoretical atmospheric and evolutionary models that incorporate deuterium burning for HD 206893c, parameterized by cloudy atmosphere models as well as a “hybrid sequence” (encompassing a transition from cloudy to cloud-free), provide a good simultaneous fit to the luminosity of both HD 206893B and c. Thus, accounting for both deuterium burning and clouds is crucial to understanding the luminosity evolution of HD 206893c. Conclusions. In addition to using long-term RV information, this effort is an early example of a direct imaging discovery of a bona fide exoplanet that was guided in part by Gaia astrometry. Utilizing Gaia astrometry is expected to be one of the primary techniques going forward for identifying and characterizing additional directly imaged planets. In addition, HD 206893c is an example of an object narrowly straddling the deuterium-burning limit but unambiguously undergoing deuterium burning. Additional discoveries like this may therefore help clarify the discrimination between a brown dwarf and an extrasolar planet. Lastly, this discovery is another example of the power of optical interferometry to directly detect and characterize extrasolar planets where they form, at ice-line orbital separations of 2−4 au.more » « less
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