3,169 research outputs found
Gamma-ray emission from Wolf-Rayet stars interacting with AGN jets
No full textDense populations of stars surround the nuclear regions of galaxies. Inthis work, we study the interaction of a WR star with relativistic jetsin active galactic nuclei. A bow-shaped double-shock structure will formas a consequence of the interaction of the jet and the wind of the star.Particles can be accelerated up to relativistic energies in these shocksand emit high-energy radiation. We compute the produced γ-ray emission obtaining that this radiation may be significant. This emissionis expected to be particularly relevant for nearby non-blazar sources.Fil: Araudo, Anabella Teresa. Centro de Radioastronomía y Astrofísica. Unam; MéxicoFil: Valenti Bosch-Ramon. Universidad de Barcelona; EspañaFil: Romero, Gustavo Esteban. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; Argentina5th International Meeting on High Energy Gamma-Ray AstronomyHeidelbergAlemaniaMax-Planck-Institute for Nuclear Physic
High-energy flares from jet-clump interactions
No full textHigh-mass microquasars are binary systems composed by a massive star and a compact object from which relativistic jets are launched. Regarding the companion star, observational evidence supports the idea that winds of hot stars are formed by clumps. Then, these inhomogeneities may interact with the jets producing a flaring activity. In the present contribution we study the interaction between a jet and a clump of the stellar wind in a high-mass microquasar. This interaction produces a shock in the jet, where particles may be accelerated up to relativistic energies. We calculate the spectral energy distributions of the dominant non-thermal processes: synchrotron radiation, inverse Compton scattering, and proton-proton collisions. Significant levels of X- and γ-ray emission are predicted, with luminosities in the different domains up to ∼1034–1035 erg s-1 on a timescale of about ∼1 h. Finally, jet-clump interactions in high-mass microquasars could be detectable at high energies. These phenomena may be behind the fast TeV variability found in some high-mass X-ray binary systems, such as Cygnus X-1, LS 5039 and LS I+61 303. In addition, our model can help to derive information on the properties of jets and clumpy winds.Fil: Araudo, Anabella Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Instituto Argentino de Radioastronomia (i); Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Bosch Ramon, Valenti. Max Planck Institut fur Kernphysik, Heidelberg; AlemaniaFil: Romero, Gustavo Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Instituto Argentino de Radioastronomia (i); Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentin
Gamma-rays from massive protostars
No full textMassive protostars have associated bipolar outflows with velocities of hundreds of km s-1. Such outflows produce strong shocks when interact with the ambient medium leading to regions of non-thermal radio emission. Under certain conditions, the population of relativistic particles accelerated at the terminal shocks of the protostellar jets can produce significant gamma-ray emission. We estimate the conditions necessary for high-energy emission in the non-thermal hot spots of jets associated with massive protostars embedded in dense molecular clouds. Our results show that particle-matter interactions can lead to the detection of molecular clouds hosting massive young stellar objects by the Fermi satellite at MeV-GeV energies and even by Cherenkov telescope arrays in the GeV-TeV range. Astronomy at gamma-rays can be used to probe the physical conditions in star forming regions and particle acceleration processes in the complex environment of massive molecular clouds.Fil: Romero, Gustavo Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto Argentino de Radioastronomia (i); Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Araudo, Anabella Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto Argentino de Radioastronomia (i); Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Bosch Ramon, Valenti. Max Planck Institut fur Kernphysik; AlemaniaFil: Paredes, Josep María. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciéncies del Cosmos; Españ
La prevenció de la violencia. L’esport com a instrument de resolució de conflictes, cohesió i convivència social entre els infants i els joves
No full textEn aquest article es recull la recerca elaborada en el marc de la Càtedra Ethos de la Universitat Ramon Llull sobre l’esport com a eina d’integració social. El fenomen de l’esport és una de les manifestacions més polièdriques de la societat contemporània que permet múltiples abordatges. En aquest article s’exposen les conclusions d’una recerca empírica que demostra com la pràctica esportiva és un poderós instrument d’integració social en el món dels joves.In this article you can read the research elaborated in the framework of the Ethos Chair of the Ramon Llull University on the sport as an instrument of social inclusion. The sport is one of the most multifaceted manifestations of contemporary society that permits multiple approaches. In this article, the author exposes the conclusions of an empirical research that demonstrates the sports practice is a power instrument of social integration in the world of youth
La prevenció de la violencia. L’esport com a instrument de resolució de conflictes, cohesió i convivència social entre els infants i els joves
No full textEn aquest article es recull la recerca elaborada en el marc de la Càtedra Ethos de la Universitat Ramon Llull sobre l’esport com a eina d’integració social. El fenomen de l’esport és una de les manifestacions més polièdriques de la societat contemporània que permet múltiples abordatges. En aquest article s’exposen les conclusions d’una recerca empírica que demostra com la pràctica esportiva és un poderós instrument d’integració social en el món dels joves.In this article you can read the research elaborated in the framework of the Ethos Chair of the Ramon Llull University on the sport as an instrument of social inclusion. The sport is one of the most multifaceted manifestations of contemporary society that permits multiple approaches. In this article, the author exposes the conclusions of an empirical research that demonstrates the sports practice is a power instrument of social integration in the world of youth
The interplay of author and editor gender in acceptance delays: evidence from accounting journals
No full textThe objective of this study is to examine the impact of the gender of editors and authors, as well as their interaction, on acceptance delays (ACCDEL) of articles. We focus on genders of the corresponding author and the editor overseeing the manuscript. Using data from three top accounting journals from 2015 to 2020, we conduct a regression analysis to test the hypotheses regarding longer ACCDEL for articles under female editorship or authors, those with gender-opposite editor-author pairs, and those with coincident genders editor-author pairs. We find that when the genders of editors and corresponding authors differ, there is a significant increase in ACCDEL compared to submissions where the genders of editors and corresponding authors match. Our results suggest the existence of a prevalent gender homophily effect.info:eu-repo/semantics/publishedVersio
La prevenció de la violencia. L’esport com a instrument de resolució de conflictes, cohesió i convivència social entre els infants i els joves
No full textEn aquest article es recull la recerca elaborada en el marc de la Càtedra Ethos de la Universitat Ramon Llull sobre l’esport com a eina d’integració social. El fenomen de l’esport és una de les manifestacions més polièdriques de la societat contemporània que permet múltiples abordatges. En aquest article s’exposen les conclusions d’una recerca empírica que demostra com la pràctica esportiva és un poderós instrument d’integració social en el món dels joves.In this article you can read the research elaborated in the framework of the Ethos Chair of the Ramon Llull University on the sport as an instrument of social inclusion. The sport is one of the most multifaceted manifestations of contemporary society that permits multiple approaches. In this article, the author exposes the conclusions of an empirical research that demonstrates the sports practice is a power instrument of social integration in the world of youth
Electrified Haber-Bosch Process: Green Ammonia Production
No full textThis report provides a design for a new process to make the ammonia-producing Haber-Bosch process more sustainable by reducing its CO2 emissions. It presents different elements of a process design with most importantly; process diagrams, mass and energy balances and a techno-economic analysis. The most important differences in this process is the use of water electrolysis and nitrogen production. This process emits approximately 50% less CO2 than regular Haber-Bosch methods. Nevertheless, the techno-economic analysis shows that this method is very expensive and that ammonia can only be sold at an acceptable price conform to the market with subsidies on electricity prices and can only become competitive if CO2 taxes are implemented for classic Haber-Bosch plants.Renewables Based Energy Conversion and StorageWB3595 Design ProjectMechanical Engineering | Process and Energy Technolog
Raonament intel·lectual i materialitat del text: el cas de l'Ars inventiva veritatis de Ramon Llull
No full textRamon Llull's Ars inventiva veritatis (1290) is conserved in a manuscript closely connected with the author. The peculiar and complex disposition of the text of this codex permits us to study the careful organization of the work, revealing Llull's desire to guide the reader in certain specific directions. This makes evident, once again, the interrelation between the materiality and significance of the text
Low-frequency radio observations of the MGRO J2019+37 Complex
No full textWe present here a preliminary account of the results of a wide-field mosaic obtained at 610 MHz (49 cm) with the Giant Metre-wave Radio Telescope (GMRT) in India covering the field of the unidentified TeV source MGRO J2019+37. A catalogue of all radio sources detected has been created including both compact and extended objects. Their observational properties are described and presented. We draw the attention to some peculiar objects inside the ˜1° uncertainty region of the TeV emission. The possible connection of these sources with the MILAGRO γ-ray emission will be assessed in future work.Fil: Sánchez Sutil, Juan R. . Universidad de Jaén; EspañaFil: Paredes, Josep M.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Moldón, J.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Zabalza, V.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Bordas, P.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Ribó, M.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Martí, Josep. Universidad de Jaén; EspañaFil: Muñoz Arjonilla, Alvaro J.. Universidad de Jaén; EspañaFil: Luque Escamilla, Pedro L.. Universidad de Jaén; EspañaFil: Ishwara Chandra, C. H.. NCRA. TIFR; IndiaFil: Peracaula, Marta. Universidad de Girona; EspañaFil: Bosch Ramon, Valenti. Max Planck Institut Fur Kernphysik, Heidelberg; AlemaniaFil: Romero, Gustavo Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto Argentino de Radioastronomia (i); Argentin
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