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  1. Numerous numerical studies have been carried out in recent years that simulate different aspects of star-planet interactions. These studies focus mostly on hot Jupiters with sun-like stars. However, more realistic simulations require the inclusion of a wide range of stellar types in the study of stellar-planetary interactions. In this study, I use MHD simulations to model star-planet interactions assuming different stellar types and a Jovian exoplanet. 
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  2. Abstract

    High latitude upper atmospheric inter‐hemispheric asymmetry (IHA) tends to be enhanced during geomagnetic storms, which may be due to the complex spatiotemporal changes and magnitude modifications in field aligned currents (FACs) and particle precipitation (PP). However, the relative contribution of FACs and PP to IHA in high‐latitude forcing and energy is not well understood. The IHA during the 2015 St. Patrick’s Day storm has been investigated using the global ionosphere thermosphere model (GITM), driven by FACs from the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) and PP from the Assimilative Mapping of Ionospheric Electrodynamics (AMIE). A comprehensive study of the (a) relative contributions of FACs and PP to electric potential and Joule heating and (b) sensitivity of electric potential and Joule heating to the changes in magnitude and distribution of FACs and PP is presented. The results indicate that FACs lead to larger potential and Joule heating changes compared with PP. The spatial variations of potential and Joule heating are also affected by variation in FACs. As for asymmetric magnitude and distribution, it is found that electric potential and Joule heating are more sensitive to changes in the distribution of FACs and PP than the magnitude of FACs and PP. A new spatial asymmetry index (SAI) is introduced, which reveals spatial asymmetric details that are often overlooked by previous studies. This sensitivity study reveals the relative contributions in high‐latitude forcing and emphasizes the importance of obtaining accurate FACs and PP in both hemispheres.

     
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    Free, publicly-accessible full text available April 1, 2025
  3. 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. 
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    Free, publicly-accessible full text available January 1, 2025
  4. Although global magnetohydrodynamic (MHD) models have increased in sophistication and are now at the forefront of modeling Space Weather, there is still no clear understanding of how well these models replicate the observed ionospheric current systems. Without a full understanding and treatment of the ionospheric current systems, global models will have significant shortcomings that will limit their use. In this study we focus on reproducing observed seasonal interhemispheric asymmetry in ionospheric currents using the Space Weather Modeling Framework (SWMF). We find that SWMF does reproduce the linear relationship between the electrojets and the FACs, despite the underestimation of the currents’ magnitudes. Quantitatively, we find that at best SWMF is only capturing approximately 60% of the observed current. We also investigate how varying F10.7 effects the ionospheric potential and currents during the summer and winter. We find that simulations ran with higher F10.7 result in lower ionospheric potentials. Additionally, we find that the models do not always replicate the expected behavior of the currents with varying F10.7. This work points to a needed improvement in ionospheric conductance models.

     
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  5. Quantum information science (QIS) is of growing importance to economic and national security, commerce, and technology. The development of a "quantum smart" workforce needs to begin before college since most students will not major in physics. Thus, it is vital to expose K-12 students to quantum concepts that are relevant to everyday experiences with credit card security, phones, computers, and basic technology and to prepare teachers to teach this content. The logical venue for exposure to basic ideas in quantum science might be a high school physics course, or even a physical science course if a full physics course is not offered. Professional development (PD) for educators typically includes 1-2 weeks of intensive instruction, usually in the summer. Teachers are then expected to remember what they learned and implement it several months after the PD. The model is based on prior research indicating that an educator needs a minimum of 80 hours of PD to become comfortable enough to implement the new instruction in their classroom. However, little research has been done as to how much they actually implement. For the past three years, we have been engaged in a project funded by the US National Science Foundation to build mechanisms (materials and PD strategies) for educating a quantum-ready workforce. Our PD model is based on pedagogical techniques used in classrooms, specifically the components of learn then practice in order to avoid cognitive overload. Instruction is more effective when the learners (teachers or students) are given opportunities to actively engage in the learning process through interaction/collaboration with peers, exploring challenges, and practicing what they have learned. This paper will share the logistics of our new PD new model, challenges, finding from our current research, and implications for future PD in K-16. 
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  6. The future of economic and national security, commerce, and technology are becoming more dependent on quantum information science (QIS). In addition to traditional STEM fields, there will be a broad need to develop a "quantum smart" workforce, and this development needs to begin before college. Since most students will not major in physics, it is vital to expose precollege students to quantum concepts that are relevant to everyday experiences with information security, smart phones, computers, and other widely used technology. This project, funded by the US National Science Foundation, provides opportunities for students to learn about various aspects of quantum science, regardless of whether they take a physics class. This project provides opportunities for secondary educators to learn and practice QIS. Project partners include universities, businesses, and professional organizations such as Science Teacher Association in Utah and Texas, American Association of Physics Teachers, Institute for Quantum Computing, and Perimeter Institute for Theoretical Physics. In particular, we utilize a trainer of trainer approach, however, 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. In this paper we will discuss the content areas and provide an outline of the professional development model. 
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  7. Intense currents produced during geomagnetic storms dissipate energy in the ionosphere through Joule heating. This dissipation has significant space weather effects, and thus it is important to determine the ability of physics-based simulations to replicate real events quantitatively. Several empirical models estimate Joule heating based on ionospheric currents using the AE index. In this study, we select 11 magnetic storm simulations from the CCMC database and compare the integrated Joule heating in the simulations with the results of empirical models. We also use the SWMF global magnetohydrodynamic simulations for 12 storms to reproduce the correlation between the simulated AE index and simulated Joule heating. We find that the scale factors in the empirical models are half what is predicted by the SWMF simulations.

     
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  8. Magnetopause location is an important prediction of numerical simulations of the magnetosphere, yet the models can err, either under-predicting or over-predicting the motion of the boundary. This study compares results from two of the most widely used magnetohydrodynamic (MHD) models, the Lyon–Fedder–Mobarry (LFM) model and the Space Weather Modeling Framework (SWMF), to data from the GOES 13 and 15 satellites during the geomagnetic storm on 22 June 2015, and to THEMIS A, D, and E during a quiet period on 31 January 2013. The models not only reproduce the magnetopause crossings of the spacecraft during the storm, but they also predict spurious magnetopause motion after the crossings seen in the GOES data. We investigate the possible causes of the over-predictions during the storm and find the following. First, using different ionospheric conductance models does not significantly alter predictions of the magnetopause location. Second, coupling the Rice Convection Model (RCM) to the MHD codes improves the SWMF magnetopause predictions more than it does for the LFM predictions. Third, the SWMF produces a stronger ring current than LFM, both with and without the RCM and regardless of the LFM spatial resolution. During the non-storm event, LFM predicts the THEMIS magnetopause crossings due to the southward interplanetary magnetic field better than the SWMF. Additionally, increasing the LFM spatial grid resolution improves the THEMIS predictions, while increasing the SWMF grid resolutions does not.

     
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