Observation of extragalactic sources of very high energy gamma-rays with the MAGIC telescope

MAGIC is currently the largest single dish ground-based imaging air Cherenkov telescope in operation. During its first cycle of observations more than 20 extragalactic objects have been observed, and very high energy gamma-ray signals have been detected in several of them. The results of this observations are presented, together with a discussion of the spectral characteristics and the flux variability of the detected sources.Comment: 6 pages, 3 figures, to appear in the proceedings of the International School of Cosmics Ray Astrophysics (ISCRA) 15th Course: Astrophysics at Ultra-High Energies, Erice, Sicily, Italy, 20-27 Jun 200

Low-power optical beam steering by microelectromechanical waveguide gratings

Optical beam steering is key for optical communications, laser mapping (LIDAR), and medical imaging. For these applications, integrated photonics is an enabling technology that can provide miniaturized, lighter, lower cost, and more power efficient systems. However, common integrated photonic devices are too power demanding. Here, we experimentally demonstrate, for the first time, beam steering by microelectromechanical (MEMS) actuation of a suspended silicon photonic waveguide grating. Our device shows up to 5.6{\deg} beam steering with 20 V actuation and a power consumption below the $\mu$W level, i.e. more than 5 orders of magnitude lower power consumption than previous thermo-optic tuning methods. The novel combination of MEMS with integrated photonics presented in this work lays ground for the next generation of power-efficient optical beam steering systems

MAGIC descobreix una nova font de raigs gamma

El telescopi MAGIC o "gran telescopi d'imatge Cherenkov de raigs gamma" ha descobert una nova font celeste de raigs gamma. Aquest nou objecte localitzat per MAGIC és un nucli actiu de la galàxia anomenat 3C 66A, és a dir, un forat negre d'immenses dimensions del qual emanen partícules de llum de l'energia més alta. Aquest objecte, descobert per telescopis de ràdio als setanta, ha estat observat per MAGIC en la banda dels raigs gamma de molta alta energia, amb resultats desconcertants. De fet, no s'ha pogut identificar completament que l'emissió de raigs gamma detectada per MAGIC provingui de 3C 66A. Aquest descobriment, en el qual ha participat l'Institut de Física d'Altes Energies (IFAE), ha estat publicat recentment a la revista Astrophysical Journal Letters.El telescopio MAGIC o "gran telescopio de imagen Cherenkov de rayos gamma" ha descubierto una nueva fuente celeste de rayos gamma. Este nuevo objeto localizado por MAGIC es un núcleo activo de la galaxia llamado 3C 66A, es decir, un agujero negro de inmensas dimensiones del cual emanan partículas de luz de la energía más alta. Este objeto, descubierto por telescopios de radio en los años setenta, ha sido observado por MAGIC en la banda de los rayos gamma de muy alta energía, con resultados desconcertantes. De hecho, no se ha podido identificar por completo que la emisión de rayos gamma detectada por MAGIC provenga de 3C 66A. Este descubrimiento, en el cual ha participado el Instituto de Física de Altas Energías (IFAE), ha sido publicado recientemente en la revista Astrophysical Journal Letters

Advertising communication and spirituality: a critical approach of academics and professionals

This article explores advertising as a space where spiritual discourses are reproduced from the critical approach of academics in communication and sociology, along with professionals in the advertising sector. Therefore, a qualitative methodology of semi-structured interviews with a panel of fifteen experts was used. This research aims to develop a discourse derived from the interviewee’s experience of the meaning provided by advertising as a transcendent dimension. The interviews were analysed by applying a spiral model by simple induction. The study identifies a compensatory character between brands and religions based on a functional definition of the latter, where brands have acquired the ability to construct social meaning, offer an existential programme to the individual, and arouse identity and awareness through their own narration. Without disregarding the economic objective of corporations or the different levels of transcendence expressed by brands and religious forms, there is consensus on advertising’s attempt to follow the same scheme of adhesion, claims, symbology, and evocations offered by religions, assuming a post-materialist turn of the advertising discourse towards transcendental values, even superficially or banally. The list of interviewees and the use of this technique, which has not previously been applied to the interactions between advertising discourse and spirituality, provide an original perspective on this emerging study fiel