bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dipolar stability in spherical simulations: The impact of an inner stable zone
Authors: Zaire Bonnie , Jouve Laurène 
Published: September 2020

AbstractMagnetic fields vary in complexity for different stars. The stability of dipolar magnetic fields is known to depend on different quantities, e.g., the stellar rotation, the stratification, and the intensity of convective motions. Here, we study the dipolar stability in a system with an inner stable zone. We present preliminary results of dynamo simulations using the Rayleigh number as a control parameter. The stiffness of the stable zone is accordingly varied to keep a constant ratio of the Brunt-Väisälä frequency to the angular velocity. Similarly to the completely convective spherical shell, we find that a transition exists between a regime where the magnetic field is dipolar to a multipolar regime when the Rossby number is increased. The value of the Rossby number at the transition is very close to the one of the fully convective case.
Star-planet interaction through spectral lines
Authors: Villarreal D’Angelo C. , Vidotto A. A. , Esquivel A. , Sgró M. A. , Koskinen T. , Fossati L. 
Published: September 2020

AbstractThe growth of spectroscopic observations of exoplanetary systems allows the possibility of testing theoretical models and studying the interaction that exoplanetary atmospheres have with the wind and the energetic photons from the star. In this work, we present a set of numerical 3D simulations of HD 209458b for which spectral lines observations of their evaporative atmosphere are available. The different simulations aim to reproduce different scenarios for the star-planet interaction. With our models, we reconstruct the Lyα line during transit and compare with observations. The results allows us to analyse the shape of the line profile under these different scenarios and the comparison with the observations suggest that HD209458b may have a magnetic field off less than 1 G. We also explore the behaviour of the magnesium lines for models with and without magnetic fields.
Revisiting the building blocks of solar magnetic fields by GREGOR
Authors: Utz Dominik , Kuckein Christoph , Campos Rozo Jose Iván , González Manrique Sergio Javier , Balthasar Horst , Gömöry Peter , Hernández Judith Palacios , Denker Carsten , Verma Meetu , Kontogiannis Ioannis , Krikova Kilian , Hofmeister Stefan , Diercke Andrea 
Published: September 2020

AbstractThe Sun is our dynamic host star due to its magnetic fields causing plentiful of activity in its atmosphere. From high energetic flares and coronal mass ejections (CMEs) to lower energetic phenomena such as jets and fibrils. Thus, it is of crucial importance to learn about formation and evolution of solar magnetic fields. These fields cover a wide range of spatial and temporal scales, starting on the larger end with active regions harbouring complex sunspots, via isolated pores, down to the smallest yet resolved elements – so-called magnetic bright points (MBPs). Here, we revisit the various manifestations of solar magnetic fields by the largest European solar telescope in operation, the 1.5-meter GREGOR telescope. We show images from the High-resolution Fast Imager (HiFI) and spectropolarimetric data from the GREGOR Infrared Spectrograph (GRIS). Besides, we outline resolved convective features inside the larger structures – so-called light-bridges occurring on large to mid-sized scales.
Trigger mechanisms of the major solar flares
Authors: Yang Shuhong 
Published: September 2020

AbstractSolar flares, suddenly releasing a large amount of magnetic energy, are one of the most energetic phenomena on the Sun. For the major flares (M- and X-class flares), there exist strong-gradient polarity-inversion lines in the pre-flare photospheric magnetograms. Some parameters (e.g., electric current, shear angle, free energy) are used to measure the magnetic non-potentiality of active regions, and the kernels of major flares coincide with the highly non-potential regions. Magnetic flux emergence and cancellation, shearing motion, and sunspot rotation observed in the photosphere are deemed to play an important role in the energy buildup and flare trigger. Solar active region 12673 produced many major flares, among which the X9.3 flare is the largest one in solar cycle 24. According to the newly proposed block-induced eruption model, the block-induced complex structures built the flare-productive active region and the X9.3 flare was triggered by an erupting filament due to the kink instability.
Exploring Flaring Behaviour on Low Mass Stars, Solar-type Stars and the Sun
Authors: Doyle L. , Ramsay G. , Doyle J. G. , Wyper P. F. , Scullion E. , Wu K. , McLaughlin J. A. 
Published: September 2020

AbstractWe report on our project to study the activity in both the Sun and low mass stars. Utilising high cadence, Hα observations of a filament eruption made using the CRISP spectropolarimeter mounted on the Swedish Solar Telescope has allowed us to determine 3D velocity maps of the event. To gain insight into the physical mechanism which drives the event we have qualitatively compared our observation to a 3D MHD reconnection model. Solar-type and low mass stars can be highly active producing flares with energies exceeding erg. Using K2 and TESS data we find no correlation between the number of flares and the rotation phase which is surprising. Our solar flare model can be used to aid our understanding of the origin of flares in other stars. By scaling up our solar model to replicate observed stellar flare energies, we investigate the conditions needed for such high energy flares.
From the Sun to solar-type stars: radial velocity, photometry, astrometry and logR′HK time series for late-F to early-K old stars
Authors: Meunier Nadège , Lagrange Anne-Marie 
Published: September 2020

AbstractSolar simulations and observations showed that the detection of Earth twins around Sun-like stars is difficult in radial velocities with current methods techniques. The Sun has proved to be very useful to test processes, models, and analysis methods. The convective blueshift effect, dominating for the Sun, decreases towards lower mass stars, providing more suitable conditions to detect low mass planets. We describe the basic processes at work and how we extended a realistic solar model of radial velocity, photometry, astrometry and LogR′HK variability, using a coherent grid of stellar parameters covering a large range in mass and average activity levels. We present selected results concerning the impact of magnetic activity on Earth-mass planet detectability as a function of stellar type. We show how such realistic simulations can help characterizing the effect of stellar activity on RV and astrometric exoplanet detection.
Coherent structures and magnetic reconnection in photospheric and interplanetary magnetic field turbulence
Authors: Miranda Rodrigo A. , Chian Abraham C.-L. , Rempel Erico L. , Silva Suzana S. A. 
Published: September 2020

AbstractIn this paper it is shown that rope-rope magnetic reconnection in the solar wind can enhance multifractality in the inertial subrange and drive intermittent magnetic field turbulence. Additionally, it is shown that Lagrangian coherent structures can unveil the transport barriers of magnetic elements in the quiet Sun.
CME deflections due to magnetic forces from the Sun and Kepler-63
Authors: Menezes F. , Netto Y. , Kay C. , Opher M. , Valio A. 
Published: September 2020

AbstractThe stellar magnetic field is the driver of activity in the star and can trigger energetic flares, CMEs and ionized wind. These phenomena, specially CMEs, may have an important impact on the magnetosphere and atmosphere of the orbiting planets. To predict whether a CME will impact a planet, the effects of the background on the CME's trajectory must be taken into account. We used the MHD code ForeCAT – a model for CME deflection due to magnetic forces – to perform numerical simulations of CMEs being launched from both the Sun and Kepler-63, which is a young, solar-like star with high activity. Comparing results from Kepler-63 and the Sun gives us a panorama of the distinct activity level and star-planet interactions of these systems due to the difference of stellar ages and star-planet distances.
Temporal evolution of the velocity distribution in systems described by the Vlasov equation; Radiation Belts: Analytical and computational results
Authors: Tamburrini C Abiam , Gallo-Méndez Iván , Davis Sergio , Moya Pablo S. 
Published: September 2020

AbstractAn interesting problem in plasma physics, when approached from the point of view of Statistical Mechanics is to obtain properties of collisionless plasmas, which are described by the Vlasov equation. Through what we call the Ehrenfest procedure, which uses statistical mechanical relations we obtain expectation value relations for arbitrary observables, which allows us to study the dynamics of the Earth's Outer Radiation Belt. Focusing on the velocity fluctuations, the width of the distribution function and the pitch angle, a computer simulation was performed to describe the system in order to compare and test the Ehrenfest approach. Our results show that the change in the average width of the distribution follows the analytical relation. However, for the velocity fluctuation results are not conclusive yet and require more exploration. It remains as future work to verify the relation for the pitch angle.
Global evolution of solar magnetic fields and prediction of activity cycles
Authors: Kitiashvili Irina N. 
Published: September 2020

AbstractPrediction of solar activity cycles is challenging because physical processes inside the Sun involve a broad range of multiscale dynamics that no model can reproduce and because the available observations are highly limited and cover mostly surface layers. Helioseismology makes it possible to probe solar dynamics in the convective zone, but variations in differential rotation and meridional circulation are currently available for only two solar activity cycles. It has been demonstrated that sunspot observations, which cover over 400 years, can be used to calibrate the Parker-Kleeorin-Ruzmaikin dynamo model, and that the Ensemble Kalman Filter (EnKF) method can be used to link the modeled magnetic fields to sunspot observations and make reliable predictions of a following activity cycle. However, for more accurate predictions, it is necessary to use actual observations of the solar magnetic fields, which are available only for the last four solar cycles. In this paper I briefly discuss the influence of the limited number of available observations on the accuracy of EnKF estimates of solar cycle parameters, the criteria to evaluate the predictions, and application of synoptic magnetograms to the prediction of solar activity.
Are there local dynamo in solar polar region?
Authors: Jin Chunlan 
Published: September 2020

AbstractPolar magnetic field, as a component produced by the global dynamo, is thought to be the remant of toroidal magnetic field transported poleward from Sun’s active belt. With the improvement of instruments, more and more observations are challenging the viewpoint. Recently, we identify the bipolar magnetic emergences (BMEs) in the polar region, and find that the distribution of the magnetic axes for these BMEs shows random state, which does not follow the Joy’s law of active region. The result implies the possible existence of local dynamo in the solar polar region.
A solar cycle 25 prediction based on 4D-var data assimilation approach
Authors: Sacha Brun Allan , Pui Hung Ching , Fournier Alexandre , Jouve Laurène , Talagrand Olivier , Strugarek Antoine , Hazra Soumitra 
Published: September 2020

AbstractBased on our modern 4D-var data assimilation pipeline Solar Predict we present in this short proceeding paper our prediction for the next solar cycle 25. As requested by the Solar Cycle 25 panel call issued on January 2019 by NOAA/SWPC and NASA, we predict the timing of next minimum and maximum as well as their amplitude. Our results are the following: the minimum should have occured within the first semester of year 2019. The maximum should occur in year 2024.4 ± 6 months, with a value of the sunspot number equal to 92±10. This is in agreement with the NOAA/NASA consensus published in April 2019. Note that our prediction errors are based on 1-σ measure and do not consider all the systematics, so they are likely underestimated. We will update our prediction and error analysis regularly as more data becomes available and we improve our prediction pipeline.
The Prosperity Gospel of Coronavirus Response
Authors: Djupe Paul A. , Burge Ryan P. 
Published: September 2020

AbstractThe sweep of the coronavirus pandemic across the world and the United States offers an almost unparalleled opportunity to study how social systems cope with the threat and opportunities for collective action. In this paper, we draw on survey data collected as the United States flailed in response and before a general consensus among executive officeholders developed in the following weeks. In particular, we assess how holding prosperity gospel views strongly shaped perceptions of the virus and reactions to state responses to the virus. Research on the prosperity gospel is slowly expanding and this paper helps to highlight some missing dimensions. At a time when concerted action for the social good could be uniting the country, prosperity gospel beliefs systematically undermine that possibility by augmenting threat, raising outgroup barriers, and decreasing social trust.
A study in the use of embedded readings to improve the accessibility and understanding of Latin literature at A Level
Authors: Gall Ameila 
Published: September 2020

Part way through the second school placement of my PGCE teacher training course I began to teach Latin unseen translation, where students are given an unfamiliar passage to translate, to a Year 13 cohort of just two students. The translation element of the course was proving challenging for both students – they struggled with language comprehension, and the A Level language course seems not very accessible to students with low prior attainment. Furthermore, my second placement school is an Upper School, so students start Latin from scratch in Year 9. Because of the time constraint those who choose take GCSE do the Eduqas Latin exam, which requires that slightly less grammar and syntax needs to be covered than the OCR syllabus (for example, the ablative absolute construction is absent from the Eduqas examination, but present in the OCR). For the small number carrying on in the 6th form, this results in a linguistic shortfall which has to be made up before beginning the OCR A Level specification. This seems to be a challenge even for very able Latinists, and more so for my two students, Alice and Michael (not their real names), and had presented an added barrier to their facility in grasping and translating complex language structures, both in unseen translations and the demanding set texts. Simply ‘practising’ by going through texts together was not proving helpful, as once my oral prompts during this process were removed and they were left on their own they reverted to guesswork instead of applying their knowledge and logic to the text. Similarly poor results in translation were evident from practice literature papers which they had taken before February half term, even though these were prepared texts – while the language paper asks students to tackle short unseen translations, the literature component calls for the extensive preparation of a much longer text, from which students must translate and analyse selected passages in the examination, as well as answering a broad essay question. However, despite the fact that Alice and Michael had been through their set text in detail with their teacher and made their own translations, it appeared that, when presented with a passage from the set text in exam conditions, the language looked just as intimidating to them as if they had not seen it before, and they were equally unable to produce a sensible attempt at translation. I therefore became interested in finding ways for them to approach texts which would minimise the ‘fear factor’ and allow them to access meaning without being put off by complex syntax.
Quintus in Britannia: visiting Roman Britain with the Cambridge Latin Course
Authors: Watson James 
Published: September 2020

AbstractThis article records its author's travels to sites in Britain that either provide settings for or are relevant to the stories of the Cambridge Latin Course. A version of this article was delivered as an oral presentation, entitled ‘In the footsteps of Quintus Caecilius: visiting Roman Britain with the Cambridge Latin Course’, at the American Classical League Centennial Institute in New York in June 2019. The article provides an overview of the sites, attempts to situate them in the geography and history of Roman Britain, and considers how such knowledge might be of benefit to teachers and learners.
Impact of Droughts on Water Supply in U.S. Watersheds: The Role of Renewable Surface and Groundwater Resources
Authors: Apurv Tushar , Cai Ximing 
Published: September 2020

AbstractWe use a simplified water supply system model based on the water availability assessment via the Variable Infiltration Capacity (VIC) hydrologic model to analyze water supply droughts (WSDs), which are periods with deficient water supply. The model is applied to 27 representative watersheds of the contiguous U.S. to explore how different management strategies can be more effective in mitigating WSDs in watersheds with different drought propagation mechanisms. We find that water supply deficits during droughts (WSDDs) are generally the highest in the Great Plains watersheds, followed by the western U.S. watersheds, and lowest in the eastern U.S. watersheds. We show that different measures can be adopted to mitigate WSDs in different regions. Specifically, in the western U.S. watersheds, the conjunctive use of surface and groundwater can reduce WSDD, that is, increasing surface water utilization and using groundwater recharged through winter precipitation to supplement surface water supply during droughts. In the Great Plains region, water demands need to be brought down to sustainable levels; meanwhile switching from groundwater to surface water supply can significantly reduce WSDD as the alluvial aquifers in this region provide a stable baseflow, which can act as a steady source of water supply during droughts. In the eastern U.S. watersheds, the depletion of limited storage capacity during droughts can lead to WSDD for short periods of time, which highlights the need for expansion of storage capacity in this region.
Model Forecast Error Correction Based on the Local Dynamical Analog Method: An Example Application to the ENSO Forecast by an Intermediate Coupled Model
Authors: Hou Zhaolu , Zuo Bin , Zhang Shaoqing , Huang Fei , Ding Ruiqiang , Duan Wansuo , Li Jianping 
Published: September 2020

AbstractNumerical forecasts always have associated errors. Analog correction methods combine numerical simulations with statistical analyses to reduce model forecast errors. However, identifying appropriate analogs remains a challenging task. Here, we use the Local Dynamical Analog (LDA) method to locate analogs and correct model forecast errors. As an example, an El Niño–Southern Oscillation (ENSO) intermediate coupled model forecast error correction experiment confirms that the LDA method locates high quality analogs of states of interest and improves the model forecast performance, which is due to the initial and evolution information included in the LDA method. In addition, the LDA method can be applied using a scalar time series, which reduces the complexity of the dynamical system. The LDA method is a promising method to locate dynamic analogs and can be applied to existing numerical models and forecast results.
Impact of Martian Crustal Magnetic Field on the Ion Escape
Authors: Dubinin E. , Fraenz M. , Pätzold M. , Woch J. , McFadden J. , Fan K. , Wei Y. , Tsareva O. , Zelenyi L. 
Published: September 2020

AbstractBased on the Mars Atmosphere and Volatile EvolutioN (MAVEN) observations, we have analyzed the role of the crustal magnetic field on ion loss driven by the direct interaction of the solar wind with the Mars ionosphere. Crustal magnetic fields significantly attenuate the ion ionospheric motions and raise the flux of returning ions. On the other hand, since the ion densities in the ionosphere with strong crustal field are significantly higher than in the ionosphere with a weak crustal magnetic field, the net escape fluxes from the ionosphere with the crustal sources remain vital. The crustal magnetic field also leads to the expansion of the ionosphere and increase of the area exposed to solar wind. As a result, fluxes from higher altitudes essentially contribute to the flow pattern in Martian tail producing an excess of ion loss rate (∼15%) through the southern part of the tail. Thus, effects of inhibition and enhancement of the escape rate by the crustal magnetic field at Mars operate in competition producing a minor influence on the total ion loss.
Warm Handoff, or Cold Shoulder? An Analysis of Handoffs for Primary Care Behavioral Health Consultation on Patient Engagement and Systems Utilization
Authors: Young Nicholas D. , Mathews Brittany L. , Pan Amy Y. , Herndon Jason L. , Bleck Amanda A. , Takala Christopher R. 
Published: September 2020

Objective: Referrals initiated via the “warm handoff” (HO) common to consultation-based models of integrated primary care are theorized to add value for patient outcomes relative to referral as usual (RAU) processes often used in colocated service models. The current evaluation tested this assumption in terms of impact on patient engagement, medical system utilization, and behavioral health system utilization. Method: Short-term longitudinal data were extracted for 175 integrated behavioral health referrals across urban pediatric primary care patients. A retrospective cohort design was used to assess differences between patients exposed to an HO immediately following referral versus RAU (control). Results: Analyses revealed significant differences for patients referred via HO at different time points, including fewer primary care provider appointment no-show/same-day cancellations, greater total behavioral health encounters, and fewer days from referral to any scheduled or completed follow-up behavioral health encounter. Conclusions: Consultation via HOs was associated with some short-term benefits on patient engagement and systems utilization for urban pediatric primary care patients compared to RAU. Preliminary findings may help stakeholders leverage the need for integrated (vs. colocated) models of pediatric integrated primary care to help inform economic- or value-based decisions on program development and promote care approaches that increase the likelihood of families staying engaged in care. Implications for Impact Statement “Warm handoffs” for immediate behavioral health consultation were associated with better pediatric patient engagement compared to referral as usual. Findings can help guide improvement with integrated primary care services, although future investigations are needed to further support or refute these preliminary results.