24 research outputs found
Solar supergranulation revealed by granule tracking
Context: Supergranulation is a pattern of the velocity field at the surface
of the Sun, which has been known about for more than fifty years, however, no
satisfactory explanation of its origin has been proposed. Aims: New
observational constraints are therefore needed to guide theoretical approaches
which hesitate between scenarios that either invoke a large-scale instability
of the surface turbulent convection or a direct forcing by buoyancy. Method:
Using the 14-Mpixel CALAS camera at the Pic-du-Midi observatory, we obtained a
7.5h-long sequence of high resolution images with unprecedented field size.
Tracking granules, we have determined the velocity field at the Sun's surface
in great detail from a scale of 2.5Mm up to 250Mm.
Results: The kinetic energy density spectrum shows that supergranulation
peaks at 36Mm and spans on scales ranging between 20Mm and 75Mm. The decrease
of supergranular flows in the small scales is close to a -power law,
steeper than the equipartition Kolmogorov one. The probability distribution
function of the divergence field shows the signature of intermittency of the
supergranulation and thus its turbulent nature.Comment: 4 pages, accepted in Astronomy and Astrophysics (Letters
Detector Technologies for CLIC
The Compact Linear Collider (CLIC) is a high-energy high-luminosity linear
electron-positron collider under development. It is foreseen to be built and
operated in three stages, at centre-of-mass energies of 380 GeV, 1.5 TeV and 3
TeV, respectively. It offers a rich physics program including direct searches
as well as the probing of new physics through a broad set of precision
measurements of Standard Model processes, particularly in the Higgs-boson and
top-quark sectors. The precision required for such measurements and the
specific conditions imposed by the beam dimensions and time structure put
strict requirements on the detector design and technology. This includes
low-mass vertexing and tracking systems with small cells, highly granular
imaging calorimeters, as well as a precise hit-time resolution and power-pulsed
operation for all subsystems. A conceptual design for the CLIC detector system
was published in 2012. Since then, ambitious R&D programmes for silicon vertex
and tracking detectors, as well as for calorimeters have been pursued within
the CLICdp, CALICE and FCAL collaborations, addressing the challenging detector
requirements with innovative technologies. This report introduces the
experimental environment and detector requirements at CLIC and reviews the
current status and future plans for detector technology R&D.Comment: 152 pages, 116 figures; published as CERN Yellow Report Monograph
Vol. 1/2019; corresponding editors: Dominik Dannheim, Katja Kr\"uger, Aharon
Levy, Andreas N\"urnberg, Eva Sickin
La classificació inicial en règim obert dels condemnats a presó
La classificació dels interns penats en algun dels graus penitenciaris previstos a l’ordenament jurídic espanyol és una de les funcions i tasques de l’Administració penitenciària. La classificació inicial en règim obert és una d’aquestes possibles modalitats de classificació per a un determinat conjunt de persones que complien els requisits. Aquesta modalitat de classificació ha estat fins ara poc coneguda i sovint incompresa per part de la societats, ja que s’associa amb la llibertat definitiva de l’intern sense cap tipus de control.
La finalitat de la recerca és precisament donar a conèixer els resultats d’aquesta aplicació en el conjunt de penats que l’any 2001 varen accedir a aquesta modalitat i se’ls va seguir fins a octubre de 2005, per saber la seva trajectòria i s’hi havia reincidit. També es va constituir un grup de contrast amb interns classificats en segon grau, per contrastar les diferències entre ambdós col·lectius.Esta investigación recoge las características más destacadas de aquellos clasificados inicialmente en régimen abierto en el año 2001 y se les sigue hasta octubre de 2005 para evaluar la reincidencia en el delito. Se compara con los que han estado en segundo grado y se hace un estudio específico para cada colectivo según algunas variables personales, sociofamiliares y criminológicas recogidas en los expedientes.This research shows the more important characteristics of the subjects initially classified for probation in the year 2001, and they were monitored for relapse until October 2005. The probation group is compared to a control group who were in detention. For each group results on personal, familiar and criminological features are reporte
Supergranulation, Network Formation, and TFGs Evolution from Hinode Observations
International audienc
Supergranulation, Network Formation, and TFGs Evolution from Hinode Observations
International audienc
Supergranulation, Network Formation, and TFGs Evolution from Hinode Observations
International audienc
Mars Microphone Testing and LIBS Acoustic Characterisation for the Mars 2020 Rover
International audienceResults of the SuperCam LIBS-Mars Microphone system in the Mars environment will be presented, including LIBS acoustic emission from martian soil analogs