| 1. |
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| 2. |
- Niemi, MEK, et al.
(author)
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- 2021
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swepub:Mat__t
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| 3. |
- Abel, I, et al.
(author)
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Overview of the JET results with the ITER-like wall
- 2013
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In: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 53:10, s. 104002-
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Journal article (peer-reviewed)abstract
- Following the completion in May 2011 of the shutdown for the installation of the beryllium wall and the tungsten divertor, the first set of JET campaigns have addressed the investigation of the retention properties and the development of operational scenarios with the new plasma-facing materials. The large reduction in the carbon content (more than a factor ten) led to a much lower Z(eff) (1.2-1.4) during L- and H-mode plasmas, and radiation during the burn-through phase of the plasma initiation with the consequence that breakdown failures are almost absent. Gas balance experiments have shown that the fuel retention rate with the new wall is substantially reduced with respect to the C wall. The re-establishment of the baseline H-mode and hybrid scenarios compatible with the new wall has required an optimization of the control of metallic impurity sources and heat loads. Stable type-I ELMy H-mode regimes with H-98,H-y2 close to 1 and beta(N) similar to 1.6 have been achieved using gas injection. ELM frequency is a key factor for the control of the metallic impurity accumulation. Pedestal temperatures tend to be lower with the new wall, leading to reduced confinement, but nitrogen seeding restores high pedestal temperatures and confinement. Compared with the carbon wall, major disruptions with the new wall show a lower radiated power and a slower current quench. The higher heat loads on Be wall plasma-facing components due to lower radiation made the routine use of massive gas injection for disruption mitigation essential.
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| 4. |
- Romanelli, F, et al.
(author)
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Overview of the JET results
- 2011
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In: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 51:9
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Journal article (peer-reviewed)abstract
- Since the last IAEA Conference JET has been in operation for one year with a programmatic focus on the qualification of ITER operating scenarios, the consolidation of ITER design choices and preparation for plasma operation with the ITER-like wall presently being installed in JET. Good progress has been achieved, including stationary ELMy H-mode operation at 4.5 MA. The high confinement hybrid scenario has been extended to high triangularity, lower ρ*and to pulse lengths comparable to the resistive time. The steady-state scenario has also been extended to lower ρ*and ν*and optimized to simultaneously achieve, under stationary conditions, ITER-like values of all other relevant normalized parameters. A dedicated helium campaign has allowed key aspects of plasma control and H-mode operation for the ITER non-activated phase to be evaluated. Effective sawtooth control by fast ions has been demonstrated with3He minority ICRH, a scenario with negligible minority current drive. Edge localized mode (ELM) control studies using external n = 1 and n = 2 perturbation fields have found a resonance effect in ELM frequency for specific q95values. Complete ELM suppression has, however, not been observed, even with an edge Chirikov parameter larger than 1. Pellet ELM pacing has been demonstrated and the minimum pellet size needed to trigger an ELM has been estimated. For both natural and mitigated ELMs a broadening of the divertor ELM-wetted area with increasing ELM size has been found. In disruption studies with massive gas injection up to 50% of the thermal energy could be radiated before, and 20% during, the thermal quench. Halo currents could be reduced by 60% and, using argon/deuterium and neon/deuterium gas mixtures, runaway electron generation could be avoided. Most objectives of the ITER-like ICRH antenna have been demonstrated; matching with closely packed straps, ELM resilience, scattering matrix arc detection and operation at high power density (6.2 MW m-2) and antenna strap voltages (42 kV). Coupling measurements are in very good agreement with TOPICA modelling. © 2011 IAEA, Vienna.
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| 5. |
- Kanai, M, et al.
(author)
-
- 2023
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swepub:Mat__t
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| 6. |
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| 7. |
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| 8. |
- Jones, Geraint H., et al.
(author)
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The Comet Interceptor Mission
- 2024
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In: Space Science Reviews. - : Springer Nature. - 0038-6308 .- 1572-9672. ; 220:1
-
Journal article (peer-reviewed)abstract
- Here we describe the novel, multi-point Comet Interceptor mission. It is dedicated to the exploration of a little-processed long-period comet, possibly entering the inner Solar System for the first time, or to encounter an interstellar object originating at another star. The objectives of the mission are to address the following questions: What are the surface composition, shape, morphology, and structure of the target object? What is the composition of the gas and dust in the coma, its connection to the nucleus, and the nature of its interaction with the solar wind? The mission was proposed to the European Space Agency in 2018, and formally adopted by the agency in June 2022, for launch in 2029 together with the Ariel mission. Comet Interceptor will take advantage of the opportunity presented by ESA’s F-Class call for fast, flexible, low-cost missions to which it was proposed. The call required a launch to a halo orbit around the Sun-Earth L2 point. The mission can take advantage of this placement to wait for the discovery of a suitable comet reachable with its minimum Δ V capability of 600 ms − 1 . Comet Interceptor will be unique in encountering and studying, at a nominal closest approach distance of 1000 km, a comet that represents a near-pristine sample of material from the formation of the Solar System. It will also add a capability that no previous cometary mission has had, which is to deploy two sub-probes – B1, provided by the Japanese space agency, JAXA, and B2 – that will follow different trajectories through the coma. While the main probe passes at a nominal 1000 km distance, probes B1 and B2 will follow different chords through the coma at distances of 850 km and 400 km, respectively. The result will be unique, simultaneous, spatially resolved information of the 3-dimensional properties of the target comet and its interaction with the space environment. We present the mission’s science background leading to these objectives, as well as an overview of the scientific instruments, mission design, and schedule.
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| 9. |
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| 10. |
- Thomas, HS, et al.
(author)
-
- 2019
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swepub:Mat__t
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| 11. |
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| 12. |
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| 13. |
- Alcorn, J, et al.
(author)
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Basic instrumentation for Hall A at Jefferson Lab
- 2004
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 522:3, s. 294-346
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Journal article (peer-reviewed)abstract
- The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electro-and photo-induced reactions at very high luminosity and good momentum and angular resolution for at least one of the reaction products. The central components of Hall A are two identical high resolution spectrometers, which allow the vertical drift chambers in the focal plane to provide a momentum resolution of better than 2 x 10(-4). A variety of Cherenkov counters, scintillators and lead-glass calorimeters provide excellent particle identification. The facility has been operated successfully at a luminosity well in excess of 10(38) CM-2 s(-1). The research program is aimed at a variety of subjects, including nucleon structure functions, nucleon form factors and properties of the nuclear medium. (C) 2003 Elsevier B.V. All rights reserved.
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| 14. |
- Bell, Taylor, et al.
(author)
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Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b
- 2024
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In: Nature Astronomy. - 2397-3366. ; In Press
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Journal article (peer-reviewed)abstract
- Hot Jupiters are among the best-studied exoplanets, but it is still poorly understood how their chemical composition and cloud properties vary with longitude. Theoretical models predict that clouds may condense on the nightside and that molecular abundances can be driven out of equilibrium by zonal winds. Here we report a phase-resolved emission spectrum of the hot Jupiter WASP-43b measured from 5 μm to 12 μm with the JWST’s Mid-Infrared Instrument. The spectra reveal a large day–night temperature contrast (with average brightness temperatures of 1,524 ± 35 K and 863 ± 23 K, respectively) and evidence for water absorption at all orbital phases. Comparisons with three-dimensional atmospheric models show that both the phase-curve shape and emission spectra strongly suggest the presence of nightside clouds that become optically thick to thermal emission at pressures greater than ~100 mbar. The dayside is consistent with a cloudless atmosphere above the mid-infrared photosphere. Contrary to expectations from equilibrium chemistry but consistent with disequilibrium kinetics models, methane is not detected on the nightside (2σ upper limit of 1–6 ppm, depending on model assumptions). Our results provide strong evidence that the atmosphere of WASP-43b is shaped by disequilibrium processes and provide new insights into the properties of the planet’s nightside clouds. However, the remaining discrepancies between our observations and our predictive atmospheric models emphasize the importance of further exploring the effects of clouds and disequilibrium chemistry in numerical models.
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| 15. |
- Bernado, Laura, et al.
(author)
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Vehicular Channels
- 2012
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In: LTE-Advanced and Next Generation Wireless Networks: Channel Modelling and Propagation. - : Wiley. - 9781119976707 ; , s. 153-186
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Book chapter (peer-reviewed)
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| 16. |
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| 17. |
- Bousquet, Jean, et al.
(author)
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ARIA digital anamorphosis : Digital transformation of health and care in airway diseases from research to practice
- 2021
-
In: Allergy. European Journal of Allergy and Clinical Immunology. - : John Wiley & Sons. - 0105-4538 .- 1398-9995. ; 76:1, s. 168-190
-
Research review (peer-reviewed)abstract
- Digital anamorphosis is used to define a distorted image of health and care that may be viewed correctly using digital tools and strategies. MASK digital anamorphosis represents the process used by MASK to develop the digital transformation of health and care in rhinitis. It strengthens the ARIA change management strategy in the prevention and management of airway disease. The MASK strategy is based on validated digital tools. Using the MASK digital tool and the CARAT online enhanced clinical framework, solutions for practical steps of digital enhancement of care are proposed.
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Breitbarth, Eike, et al.
(author)
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Nitrogen fixation and growth rates of Trichodesmium IMS-101 as a function of light intensity
- 2008
-
In: Marine Ecology Progess Series. - : Inter-Research Science Center. - 0171-8630 .- 1616-1599. ; 359, s. 25-36
-
Journal article (peer-reviewed)abstract
- The diazotrophic cyanobacterium Trichodesmium is a significant contributor to marine nitrogen and carbon cycles and has been incorporated in biogeochemical ocean circulation models. To date, parameterization of light as a controlling factor for nitrogen fixation has been based on field observations, where factors other than light also affect Trichodesmium physiology. Here we present data on light-dependent (15 to 1100 µmol quanta m–2 s–1) diazotrophic growth from controlled laboratory experiments and their implications for modeling approaches. We supply a simple empirical model to describe nitrogen fixation by Trichodesmium in batch cultures. Diazotrophic growth of axenic Trichodesmium IMS-101 was light saturated at 180 µmol quanta m–2 s–1 and did not vary significantly at higher photon irradiances up to 1100 µmol quanta m–2 s–1 (μcarbon based ≈ 0.26 d–1). Chlorophyll a (chl a) normalized N2 fixation rates were significantly affected by light intensity during mid-exponential growth (0.74 to 4.45 mol N fixed mol chl a–1 h–1) over the range of photon irradiances tested. In contrast, nitrogen fixation rates normalized to the cellular carbon content were relatively unaffected by light intensity (0.42 to 0.59, averaging 0.5 mmol N mol particulate organic carbon [POC]–1 h–1). Trichodesmium carbon biomass can be used to estimate the nitrogen input by this diazotroph into the ocean; the maximum input rate is 350 nmol N fixed l–1 h–1.
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| 22. |
- Carter, Aarynn L., et al.
(author)
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A benchmark JWST near-infrared spectrum for the exoplanet WASP-39 b
- 2024
-
In: Nature Astronomy. - 2397-3366. ; In Press
-
Journal article (peer-reviewed)abstract
- A combined analysis of datasets across four JWST instrument modes provides a benchmark transmission spectrum for the Saturn-mass WASP-39 b. The broad wavelength range and high resolution constrain orbital and stellar parameters to below 1%.
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| 23. |
- Cumming, Robert, 1967, et al.
(author)
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Why every observatory needs a disco ball
- 2024
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In: Physics Education. - 1361-6552 .- 0031-9120. ; 59:2
-
Journal article (peer-reviewed)abstract
- Commercial disco balls provide a safe, effective and instructive way of observing the Sun. We explore the optics of solar projections with disco balls, and find that while sunspot observations are challenging, the solar disk and its changes during eclipses are easy and fun to observe. We explore the disco ball's potential for observing the moon and other bright astronomical phenomena.
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| 24. |
- Di Benedetto, H, et al.
(author)
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Fatigue of bituminous mixtures
- 2004
-
In: Materials and Structures. - 1359-5997 .- 1871-6873. ; 37:267, s. 202-216
-
Journal article (peer-reviewed)abstract
- This paper presents an interlaboratory test campaign organized by the RILEM 182-PEB Technical Committee. In the campaign, 11 different test methods, comprising uniaxial tension/compression, 2-, 3- and 4-point bending and indirect-tension tests, were utilized in order to investigate fatigue characteristics of a dense graded asphalt concrete mixture. The testing conditions specified were sinusoidal excitation at 10Hz and 10degreesC using controlled strain and stress modes. In total, more than 150 fatigue tests were carried out during the investigation. The fatigue test results were analyzed using both classical as well as continuum damage mechanics approaches. The fatigue test results obtained using the classical fatigue approach are considerably influenced by test type and mode of loading (controlled stress or strain) used. Consequently, this approach has limited use in realistic fatigue characterization of bituminous materials and pavement structures. In contrast to the classical approach, models founded on continuum damage theory may serve to isolate intrinsic fatigue characteristics from the influence of so-called biased effects, which are largely caused by the accelerated laboratory testing. The continuum damage models investigated may constitute steps, towards a rational mechanistic fatigue characterization model, which are important for effective future pavement design.
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| 25. |
- Eberhardt, Mirjam, et al.
(author)
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H2S and NO cooperatively regulate vascular tone by activating a neuroendocrine HNO-TRPA1-CGRP signalling pathway.
- 2014
-
In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 5:Jul 15
-
Journal article (peer-reviewed)abstract
- Nitroxyl (HNO) is a redox sibling of nitric oxide (NO) that targets distinct signalling pathways with pharmacological endpoints of high significance in the treatment of heart failure. Beneficial HNO effects depend, in part, on its ability to release calcitonin gene-related peptide (CGRP) through an unidentified mechanism. Here we propose that HNO is generated as a result of the reaction of the two gasotransmitters NO and H2S. We show that H2S and NO production colocalizes with transient receptor potential channel A1 (TRPA1), and that HNO activates the sensory chemoreceptor channel TRPA1 via formation of amino-terminal disulphide bonds, which results in sustained calcium influx. As a consequence, CGRP is released, which induces local and systemic vasodilation. H2S-evoked vasodilatatory effects largely depend on NO production and activation of HNO-TRPA1-CGRP pathway. We propose that this neuroendocrine HNO-TRPA1-CGRP signalling pathway constitutes an essential element for the control of vascular tone throughout the cardiovascular system.
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| 26. |
- Esparza-Borges, E., et al.
(author)
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Detection of Carbon Monoxide in the Atmosphere of WASP-39b Applying Standard Cross-correlation Techniques to JWST NIRSpec G395H Data
- 2023
-
In: Astrophysical Journal Letters. - 2041-8213 .- 2041-8205. ; 955:1
-
Journal article (peer-reviewed)abstract
- Carbon monoxide was recently reported in the atmosphere of the hot Jupiter WASP-39b using the NIRSpec PRISM transit observation of this planet, collected as part of the JWST Transiting Exoplanet Community Early Release Science Program. This detection, however, could not be confidently confirmed in the initial analysis of the higher-resolution observations with NIRSpec G395H disperser. Here we confirm the detection of CO in the atmosphere of WASP-39b using the NIRSpec G395H data and cross-correlation techniques. We do this by searching for the CO signal in the unbinned transmission spectrum of the planet between 4.6 and 5.0 μm, where the contribution of CO is expected to be higher than that of other anticipated molecules in the planet’s atmosphere. Our search results in a detection of CO with a cross-correlation function (CCF) significance of 6.6σ when using a template with only 12C16O lines. The CCF significance of the CO signal increases to 7.5σ when including in the template lines from additional CO isotopologues, with the largest contribution being from 13C16O. Our results highlight how cross-correlation techniques can be a powerful tool for unveiling the chemical composition of exoplanetary atmospheres from medium-resolution transmission spectra, including the detection of isotopologues.
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| 27. |
- Fricke, Tabea C., et al.
(author)
-
Oxidation of methionine residues activates the high-threshold heat-sensitive ion channel TRPV2
- 2019
-
In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424. ; 116:48, s. 24359-24365
-
Journal article (peer-reviewed)abstract
- Thermosensitive transient receptor potential (TRP) ion channels detect changes in ambient temperature to regulate body temperature and temperature-dependent cellular activity. Rodent orthologs of TRP vanilloid 2 (TRPV2) are activated by nonphysiological heat exceeding 50 °C, and human TRPV2 is heat-insensitive. TRPV2 is required for phagocytic activity of macrophages which are rarely exposed to excessive heat, but what activates TRPV2 in vivo remains elusive. Here we describe the molecular mechanism of an oxidation-induced temperature-dependent gating of TRPV2. While high concentrations of H2O2 induce a modest sensitization of heat-induced inward currents, the oxidant chloramine-T (ChT), ultraviolet A light, and photosensitizing agents producing reactive oxygen species (ROS) activate and sensitize TRPV2. This oxidation-induced activation also occurs in excised inside-out membrane patches, indicating a direct effect on TRPV2. The reducing agent dithiothreitol (DTT) in combination with methionine sulfoxide reductase partially reverses ChT-induced sensitization, and the substitution of the methionine (M) residues M528 and M607 to isoleucine almost abolishes oxidation-induced gating of rat TRPV2. Mass spectrometry on purified rat TRPV2 protein confirms oxidation of these residues. Finally, macrophages generate TRPV2-like heat-induced inward currents upon oxidation and exhibit reduced phagocytosis when exposed to the TRP channel inhibitor ruthenium red (RR) or to DTT. In summary, our data reveal a methionine-dependent redox sensitivity of TRPV2 which may be an important endogenous mechanism for regulation of TRPV2 activity and account for its pivotal role for phagocytosis in macrophages.
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| 28. |
- Haug, Ferdinand M., et al.
(author)
-
Functional and structural insights into activation of TRPV2 by weak acids
- 2024
-
In: EMBO Journal. - 0261-4189 .- 1460-2075. ; 43:11, s. 2264-2290
-
Journal article (peer-reviewed)abstract
- Transient receptor potential (TRP) ion channels are involved in the surveillance or regulation of the acid-base balance. Here, we demonstrate that weak carbonic acids, including acetic acid, lactic acid, and CO2 activate and sensitize TRPV2 through a mechanism requiring permeation through the cell membrane. TRPV2 channels in cell-free inside-out patches maintain weak acid-sensitivity, but protons applied on either side of the membrane do not induce channel activation or sensitization. The involvement of proton modulation sites for weak acid-sensitivity was supported by the identification of titratable extracellular (Glu495, Glu561) and intracellular (His521) residues on a cryo-EM structure of rat TRPV2 (rTRPV2) treated with acetic acid. Molecular dynamics simulations as well as patch clamp experiments on mutant rTRPV2 constructs confirmed that these residues are critical for weak acid-sensitivity. We also demonstrate that the pore residue Glu609 dictates an inhibition of weak acid-induced currents by extracellular calcium. Finally, TRPV2-expression in HEK293 cells is associated with an increased weak acid-induced cytotoxicity. Together, our data provide new insights into weak acids as endogenous modulators of TRPV2.
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| 29. |
- Lee, Bruce Y., et al.
(author)
-
Research gaps and opportunities in precision nutrition : an NIH workshop report
- 2022
-
In: The American journal of clinical nutrition. - : Elsevier BV. - 1938-3207 .- 0002-9165. ; 116:6, s. 1877-1900
-
Journal article (peer-reviewed)abstract
- Precision nutrition is an emerging concept that aims to develop nutrition recommendations tailored to different people's circumstances and biological characteristics. Responses to dietary change and the resulting health outcomes from consuming different diets may vary significantly between people based on interactions between their genetic backgrounds, physiology, microbiome, underlying health status, behaviors, social influences, and environmental exposures. On 11-12 January 2021, the National Institutes of Health convened a workshop entitled "Precision Nutrition: Research Gaps and Opportunities" to bring together experts to discuss the issues involved in better understanding and addressing precision nutrition. The workshop proceeded in 3 parts: part I covered many aspects of genetics and physiology that mediate the links between nutrient intake and health conditions such as cardiovascular disease, Alzheimer disease, and cancer; part II reviewed potential contributors to interindividual variability in dietary exposures and responses such as baseline nutritional status, circadian rhythm/sleep, environmental exposures, sensory properties of food, stress, inflammation, and the social determinants of health; part III presented the need for systems approaches, with new methods and technologies that can facilitate the study and implementation of precision nutrition, and workforce development needed to create a new generation of researchers. The workshop concluded that much research will be needed before more precise nutrition recommendations can be achieved. This includes better understanding and accounting for variables such as age, sex, ethnicity, medical history, genetics, and social and environmental factors. The advent of new methods and technologies and the availability of considerably more data bring tremendous opportunity. However, the field must proceed with appropriate levels of caution and make sure the factors listed above are all considered, and systems approaches and methods are incorporated. It will be important to develop and train an expanded workforce with the goal of reducing health disparities and improving precision nutritional advice for all Americans.
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| 30. |
-
LTE-Advanced and Next Generation Wireless Networks : Channel Modelling and Propagation
- 2012
-
Editorial collection (peer-reviewed)abstract
- LTE- A and Next Generation Wireless Networks: Channel Modeling and Performance describes recent advances in propagation and channel modeling necessary for simulating next generation wireless systems. Due to the radio spectrum scarcity, two fundamental changes are anticipated compared to the current status. Firstly, the strict reservation of a specific band for a unique standard could evolve toward a priority policy allowing the co-existence of secondary users in a band allocated to a primary system. Secondly, a huge increase of the number of cells is expected by combining outdoor base stations with smaller cells such as pico/femto cells and relays. This evolution is accompanied with the emergence of cognitive radio that becomes a reality in terminals together with the development of self-organization capabilities and distributed cooperative behaviors. The book is divided into three parts: Part I addresses the fundamentals (e.g. technologies, channel modeling principles etc.). Part II addresses propagation and modeling discussing topics such as indoor propagation, outdoor propagation, etc. Part III explores system performance and applications (e.g. MIMO Over-the-air testing, electromagnetic safety, etc).
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| 31. |
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| 32. |
- Pathak, P., et al.
(author)
-
High-contrast imaging at ten microns : A search for exoplanets around Eps Indi A, Eps Eri, Tau Ceti, Sirius A, and Sirius B
- 2021
-
In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 652
-
Journal article (peer-reviewed)abstract
- Context. The direct imaging of rocky exoplanets is one of the major science goals of upcoming large telescopes. The contrast requirement for imaging such planets is challenging. However, the mid-IR (infrared) regime provides the optimum contrast to directly detect the thermal signatures of exoplanets in our solar neighbourhood.Aims. We aim to exploit novel fast-chopping techniques newly developed for astronomy with the aid of adaptive optics to look for thermal signatures of exoplanets around bright stars in the solar neighbourhood.Methods. We used the upgraded Very Large Telescope Imager and Spectrometer for the mid-InfraRed (VISIR) instrument with high-contrast imaging capability optimised for observations at 10 μm to look for exoplanets around five nearby (d < 4 pc) stars. The instrument provides an improved signal-to-noise ratio (S/N) by a factor of ~4 in the N-band compared to standard VISIR for a given S/N and time.Results. In this work, we achieve a detection sensitivity of sub-mJy, which is sufficient to detect a few Jupiter mass planets in nearby systems. Although no detections are made, we achieve most sensitive limits within <2″ for all the observed targets compared to previous campaigns. For ϵ Indi A and ϵ Eri, we achieve detection limits very close to the giant planets discovered by RV, with the limits on ϵ Indi A being the most sensitive to date. Our non-detection therefore supports an older age for ϵ Indi A. The results presented here are promising for high-contrast imaging and exoplanet detections in the mid-IR regime.
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| 33. |
- Pietrow, Alexander G. M., 1991-, et al.
(author)
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Center-to-limb variation of spectral lines and continua observed with SST/CRISP and SST/CHROMIS
- 2023
-
In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 671
-
Journal article (peer-reviewed)abstract
- Context. Observations of center-to-limb variations (CLVs) of spectral lines and continua provide a good test for the accuracy of models with a solar and stellar atmospheric structure and spectral line formation. They are also widely used to constrain elemental abundances, and are becoming increasingly more important in atmospheric studies of exoplanets. However, only a few such data sets exist for chromospheric lines.Aims. We aim to create a set of standard profiles by means of mosaics made with the CRISP and CHROMIS instruments of the Swedish 1-m Solar Telescope (SST), as well as to explore the robustness of said profiles obtained using this method.Methods. For each spectral line, we used a mosaic that ranges from the center to the limb. Each of these mosaics were averaged down to 50 individual spectral profiles and spaced by 0.02 in the μ scale. These profiles were corrected for p-mode oscillations, and their line parameters (equivalent width, line shift, full-width at half-maximum, and line depth) were then compared against literature values whenever possible.Results. We present a set of 50 average profiles that are spaced equidistantly along the cosine of the heliocentric angle (μ) by steps of 0.02 for five continuum points between 4001 and 7772 Å, as well as ten of the most commonly observed spectral lines at the SST (Ca II H & K, Ηβ, Mg I 5173 Å, C I 5380 Å, Fe I 6173 Å, Fe I 6301 Å, Ha, O I 7772 Å, and Ca II 8542 Å).Conclusions. The CLV of line profiles and continua are shared in the CDS as machine readable tables, providing a quantitative constraint on theoretical models that aim to model stellar atmospheres.
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| 34. |
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| 35. |
- Salah, Walaa, et al.
(author)
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Using GIS as a decision making support tool for LEED credits
- 2016. - First
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In: PLEA 2016 : Cities, Buildings, People: Towards Regenerative Environments - Cities, Buildings, People: Towards Regenerative Environments. ; 3
-
Conference paper (peer-reviewed)abstract
- Green building rating systems are voluntary tools intended to promote sustainable building process through approaching several environmental issues that include sustainable design parameters related to the construction site and others related to its surrounding context. Decision making software support tools and methods are needed to guide practitioners on minimizing building’s environmental impact especially for early design decisions. Hence, the study shows how Geographic Information Systems (GIS) is used as a decision-making support tool for assessing location and transportation (LT) together with sustainable site (SS) categories for Leadership in Energy and Environmental Design (LEED) green building rating system. The methodology is applied on the 10th of Ramadan city in Egypt; creating land suitability analysis for these two LEED categories. The analysis considers sensitive land protection, high priority development sites, surrounding density and diverse uses, and access to quality transit on the context level. It also analyses lithology type and condition as well as habitat and open spaces protection on the site level. The result shows the potential role of integrating GIS analysis as a tool for site selection credits for LEED rating systems. This allows for more data integration to set a solid base for objective decision making process based on contextual conditions. The method can be generalized and applied in similar contexts in order to attract private investments for green construction especially in new development areas.
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| 36. |
- Tufvesson, Fredrik, et al.
(author)
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Multi-User MIMO Channels
- 2012
-
In: LTE-Advanced and Next Generation Wireless Networks: Channel Modelling and Propagation. - : Wiley. - 9781119976707 ; , s. 187-214
-
Book chapter (peer-reviewed)
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| 37. |
- Viswanath, Gayathri, et al.
(author)
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Constraints on the nearby exoplanet ϵ Indi Ab from deep near- and mid-infrared imaging limits
- 2021
-
In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 651
-
Journal article (peer-reviewed)abstract
- The past decade has seen increasing efforts in detecting and characterising exoplanets using high-contrast imaging in the near- and mid-infrared, which is the optimal wavelength domain for studying old, cold planets. In this work, we present deep adaptive optics imaging observations of the nearby Sun-like star E Ind A with the NaCo (L ') and NEAR (10-12.5 microns) instruments at VLT in an attempt to directly detect its planetary companion, whose presence has been indicated from radial velocity (RV) and astrometric trends. We derive brightness limits from the non-detection of the companion with both instruments and interpret the corresponding sensitivity in mass based on both cloudy and cloud-free atmospheric and evolutionary models. For an assumed age of 5 Gyr for the system, we get detectable mass limits as low as 4.4 M-J in NaCo L ' and 8.2 M-J in NEAR bands at 1.5 ' ' from the central star. If the age assumed is 1 Gyr, we reach even lower mass limits of 1.7 M-J in NaCo L ' and 3.5 M-J in NEAR bands at the same separation. However, based on the dynamical mass estimate (3.25 M-J) and ephemerides from astrometry and RV, we find that the non-detection of the planet in these observations puts a constraint of 2 Gyr on the lower age limit of the system. NaCo offers the highest sensitivity to the planetary companion in these observations, but the combination with the NEAR wavelength range adds a considerable degree of robustness against uncertainties in the atmospheric models. This underlines the benefits of including a broad set of wavelengths for the detection and characterisation of exoplanets in direct imaging studies.
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