Search results for "STELLA"

Supernova 1987A: a Template to Link Supernovae to their Remnants

2015

The emission of supernova remnants reflects the properties of both the progenitor supernovae and the surrounding environment. The complex morphology of the remnants, however, hampers the disentanglement of the two contributions. Here we aim at identifying the imprint of SN 1987A on the X-ray emission of its remnant and at constraining the structure of the environment surrounding the supernova. We performed high-resolution hydrodynamic simulations describing SN 1987A soon after the core-collapse and the following three-dimensional expansion of its remnant between days 1 and 15000 after the supernova. We demonstrated that the physical model reproducing the main observables of SN 1987A during …

Numerical Simulations of a Flux Rope Ejection

2015

Coronal mass ejections (CMEs) are the most violent phenomena observed on the Sun. One of the most successful models to explain CMEs is the flux rope ejection model, where a magnetic flux rope is expelled from the solar corona after a long phase along which the flux rope stays in equilibrium while magnetic energy is being accumulated. However, still many questions are outstanding on the detailed mechanism of the ejection and observations continuously provide new data to interpret and put in the context. Currently, extreme ultraviolet (EUV) images from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) are providing new insights into the early phase of CME evo…

Tablas de reducción de las antiguas medidas, pesas y monedas de Castilla, Alicante, Castellón y Valencia, al nuevo sistema métrico-decimal

El happening y la creación de situaciones en dos novelas de Julio Cortázar espacios de liberación y metáfora de la escritura

2013

Julio Cortázar señaló en sus textos teóricos de finales de los sesenta la naturaleza vanguardista y radical del happening y la dificultad de la intelectualidad del momento para conceptualizarlo adecuadamente. Sus novelas 62. Modelo para armar y, sobre todo, Libro de Manuel experimentaron narrativamente con el happening y, en ciertos momentos, escenificaron propuestas cercanas a la experimentación situacionista que preconizaba Debord: algunos de sus personajes producían intervenciones en el espacio público que quebraban las inercias vitales y la percepción de la realidad de aquellos personajes que se veían afectados por ellas. Esos happenings e intervenciones situacionistas sirvieron a Cortá…

Inner Edge Drag by an Asynchronous Primary and Accretion Disc Structure In Close Binaries

1996

In this work a 3-D ‘Smoothed Particle Hydrodynamics’ ([1]; [4]; [5]) accretion disc is simulated where particles at its inner edge are dragged by a fast spinning compact central star, as in the case of the intermediate polars. The angular velocity of the central star is twice the orbital angular velocity w 0. This drag can be attributed mainly to viscous interaction in the dense compact star atmosphere, although magnetic coupling may also play a role.

Entrevista para el diario ABC

1994

Entrevista a José Vidal-Beneyto realizada por Isabel San Sebastián para el diario "ABC". Se desconoce si finalmente fue publicada.

Nanoflare Evidence from Analysis of the X-Ray Variability of an Active Region Observed with Hinode/XRT

2012

The heating of the solar corona is one of the big questions in astrophysics. Rapid pulses called nanoflares are among the best candidate mechanisms. The analysis of the time variability of coronal X-ray emission is potentially a very useful tool to detect impulsive events. We analyze the small-scale variability of a solar active region in a high cadence Hinode/XRT observation. The dataset allows us to detect very small deviations of emission fluctuations from the distribution expected for a constant rate. We discuss the deviations in the light of the pulsed-heating scenario.

Mean Interplanetary Magnetic Field Measurement Using the ARGO-YBJ Experiment

2011

The sun blocks cosmic ray particles from outside the solar system, forming a detectable shadow in the sky map of cosmic rays detected by the ARGO-YBJ experiment in Tibet. Because the cosmic ray particles are positive charged, the magnetic field between the sun and the earth deflects them from straight trajectories and results in a shift of the shadow from the true location of the sun. Here we show that the shift measures the intensity of the field which is transported by the solar wind from the sun to the earth.

The polarimetric and helioseismic imager on solar orbiter

2020

This paper describes the Polarimetric and Helioseismic Imager on the Solar Orbiter mission (SO/PHI), the first magnetograph and helioseismology instrument to observe the Sun from outside the Sun-Earth line. It is the key instrument meant to address the top-level science question: How does the solar dynamo work and drive connections between the Sun and the heliosphere? SO/PHI will also play an important role in answering the other top-level science questions of Solar Orbiter, as well as hosting the potential of a rich return in further science. SO/PHI measures the Zeeman effect and the Doppler shift in the FeI 617.3nm spectral line. To this end, the instrument carries out narrow-band imaging…

A prospective new diagnostic technique for distinguishing eruptive and noneruptive active regions

2019

This research has received funding from the Science and Technology Facilities Council (UK) through the consolidated grant ST/N000609/1 and the European Research Council (ERC) under the European Union Horizon 2020 research and innovation program (grant agreement No. 647214). This work used the DiRAC@Durham facility managed by the Institute for Computational Cosmology on behalf of the STFC DiRAC HPC Facility (www.dirac.ac.uk). The equipment was funded by BEIS capital funding via STFC capital grants ST/P002293/1, ST/R002371/1, and ST/S002502/1, Durham University and STFC operations grant ST/R000832/1. DiRAC is part of the National e-Infrastructure. S.L.Y. would like to acknowledge STFC for sup…