La théorie d’Einstein validée dans des conditions extrêmes. COUPLE. Les étoiles binaires sont des objets composés de deux étoiles orbitant autour d'un centre de gravité commun. De tels couples, les astronomes en ont identifié de nombreux dans l’univers. Reste que la binaire étudiée ici est exceptionnelle. Elle est constituée d'une étoile à neutrons (c'est-à-dire le vestige de l’explosion d’une étoile massive) extrêmement dense autour de laquelle gravite une naine blanche, elle-même issue de l'évolution d'une étoile de masse modérée.
Un duo infernal L'étoile à neutrons émet des ondes radio que les radiotélescopes disséminés sur Terre peuvent capter - on appelle pulsar cette catégorie d’étoiles. Elle est deux fois plus lourde que le Soleil mais son diamètre est inférieur à 20 kilomètres et elle tourne sur elle-même 25 fois par seconde. SUCRE. Quant à sa compagne binaire, elle fait le tour du pulsar en deux heures et demie. Ondes gravitationnelles. Faster-than-light neutrino anomaly. Fig. 1 What OPERA saw. Leftmost is the proton beam from the CERNSPS accelerator. It passes the beam current transformer (BCT), hits the target, creating first, pions and then, somewhere in the decay tunnel, neutrinos. The red lines are the CERN Neutrinos to Gran Sasso (CNGS) beam to the LNGS lab where the OPERA detector is. The proton beam is timed at the BCT. In 2011, the OPERA experiment mistakenly observed neutrinos appearing to travel faster than light.
OPERA scientists announced the results of the experiment in September 2011 with the stated intent of promoting further inquiry and debate. On June 8, 2012 CERN research director Sergio Bertolucci declared on behalf of the four Gran Sasso teams, including OPERA, that the speed of neutrinos is consistent with that of light. On July 12, 2012 OPERA updated their paper by including the new sources of errors in their calculations.
Detection[edit] First results[edit] Internal replication[edit] Measurement errors[edit] End results[edit] Time of flight between a Source and a Detector observed from a Satellite. The hammock physicist. RACLETTE: A model for evaluating the thermal response of plasma facing components to slow high power plasma transients. Part I: Theory and description of model capabilities (April 1997) · Q-Sensei. Abstract RACLETTE (Rate Analysis Code for plasma Energy Transfer Transient Evaluation), a comprehensive but relatively simple and versatile model, was developed to help in the design analysis of plasma facing components (PFCs) under 'slow' high power transients, such as those associated with plasma vertical displacement events.
The model includes all the key surface heat transfer processes such as evaporation, melting, and radiation, and their interaction with the PFC block thermal response and the coolant behaviour. This paper represents part I of two sister and complementary papers. It covers the model description, calibration and validation, and presents a number of parametric analyses shedding light on and identyifing trends in the PFC armour block response to high plasma energy deposition transients. Parameters investigated include the plasma energy density and deposition time, the armour thickness and the presence of vapour shielding effects. Details.