172 research outputs found
Comentarios de las noticias: la pesadilla de los cibermedios
Media have quickly integrated audience participation on their websites, and comments on the news have become very popular. But this participation has produced many problems and discussions. The strategies media have implemented
to reduce the problems that arise are described
Heavy neutrino decays at MiniBooNE
It has been proposed that a sterile neutrino \nu_h with m_h \approx 50 MeV
and a dominant decay mode (\nu_h -> \nu\gamma) may be the origin of the
experimental anomaly observed at LSND. We define a particular model that could
also explain the MiniBooNE excess consistently with the data at other neutrino
experiments (radiative muon capture at TRIUMF, T2K, or single photon at NOMAD).
The key ingredients are (i) its long lifetime (\tau_h\approx 3-7x10^{-9} s),
which introduces a 1/E dependence with the event energy, and (ii) its Dirac
nature, which implies a photon preferably emitted opposite to the beam
direction and further reduces the event energy at MiniBooNE. We show that these
neutrinos are mostly produced through electromagnetic interactions with nuclei,
and that T2K observations force BR(\nu_h -> \nu_\tau\gamma) \le 0.01 \approx
BR(\nu_h -> \nu_\mu\gamma). The scenario implies then the presence of a second
sterile neutrino \nu_{h'} which is lighter, longer lived and less mixed with
the standard flavors than \nu_h. Since such particle would be copiously
produced in air showers through (\nu_h -> \nu_{h'}\gamma) decays, we comment on
the possible contamination that its photon-mediated elastic interactions with
matter could introduce in dark matter experiments.Comment: 18 pages, typo in Eq.(6) correcte
Heavy-neutrino decays at neutrino telescopes
It has been recently proposed that a sterile neutrino \nu_h of mass
m_h=40--80 MeV, mixing |U_{\mu h}|^2=10^{-3}--10^{-2}, lifetime \tau_h \lsim
10^{-9} s, and a dominant decay mode (\nu_h \to \nu_\mu \gamma) could be the
origin of the experimental anomalies observed at LSND, KARMEN and MiniBooNE.
Such a particle would be abundant inside air showers, as it can be produced in
kaon decays (K -> \nu_h \mu, K_L -> \nu_h \pi \mu). We use the Z-moment method
to evaluate its atmospheric flux and the frequency of its decays inside
neutrino telescopes. We show that the \nu_h would imply around 10^4 contained
showers per year inside a 0.03 km^3 telescope like ANTARES or the DeepCore in
IceCube. These events would have a characteristic energy and zenith-angle
distribution (E_\nu = 0.1--10 TeV and \theta < 90^o), which results from a
balance between the reach of the heavy neutrino (that disfavors low energies)
and a sizeable production rate and decay probability. The standard background
from contained neutrino events (\nu_e N \to e X and neutral-current
interactions of high inelasticity) is 100 times smaller. Therefore, although it
may be challenging from an experimental point of view, a search at ANTARES and
IceCube could confirm this heavy-neutrino possibility.Comment: 10 pages. Comments on constraints from muon capture and cosmology
added, minor corrections, references added. Version to appear as a Rapid
Communication in PR
Models de participació de les audiències en mitjans digitals catalans: anàlisi de La Vanguardia, El Periódico, Vilaweb i 3cat24
El present article té com a finalitat presentar diferents models d'adopció de la participació dels lectors en webs informatius. Presentem els casos de La Vanguardia, El Periódico, Vilaweb i el 3cat24, tots ells mitjans de referència en l'àmbit català. S'ha realitzat un estudi de les opcions de participació que presenten cada un dels mitjans objecte d'anàlisi, partint d'una fitxa d'estudi que permet realitzar comparacions i comprovar quins mecanismes de participació adopta cada un dels webs estudiats. En una segona fase, s'han entrevistat els responsables dels webs o de la corresponent secció de participació, amb l'objectiu de comparar les dades obtingudes en l'aplicació de la fitxa d'estudi amb les opinions de les persones entrevistades i identificar els motius per obrir els seus mitjans a la participació de l'audiència.Models of audience participation in Catalan news sites: analysis of La Vanguardia, El Periódico, Vilaweb and 3cat24. This article aims to present different models of audience participation in informative (journalistic) websites. We report on the cases of La Vanguardia, El Periódico, Vilaweb and 3cat24, all within the Catalan media field. Firstly, we analysed the participation mechanism used by each of the news sites. Subsequently, we interviewed the online editors or the community managers in order to complete the data obtained from interviewee opinions and to assess the motivation behind opening their websites to audience participation and their observations regarding the benefits of participation
Presencia y uso de internet en las redacciones catalanas
Se pretende observar el grado de penetración de internet en las redacciones de los medios catalanes y analizar hasta que punto la red está modificando las rutinas profesionales. Para ello se dispone de los resultados obtenidos de una encuesta realizada entre los miembros del Col.legi de Periodistes de Catalunya. Los resultados sugieren que internet está absolutamente integrada en las rutinas profesionales. A pesar de ello, internet no se muestra todavía como un medio indispensable para la práctica periodística, existiendo poca confianza en él como origen de un hecho noticiable
Digital media in 2014: an alternative balance
Some aspects that have characterized the evolution of online media over the last year are analysed, paying special attention to pending matters still to be addressed. Since the advent of the internet, media have delegated their survival to technological innovations, and 2014 was no exception. Data journalism, robot journalism, and hi-tech journalism..., are some of the labels devised for different technological models by online media worldwide last year. However, user-centred innovations are the most creative and potentially successful ones
Media and mobile devices. In search of El Dorado.
The spread of mobile devices –smartphones and tablets– does not go unnoticed by media companies, and particularly by press companies, which have seen in mobile content a new and profitable source of income. The aim of this article is to explain how newspapers are adopting mobile strategies and the business model behind their strategies
Journalism and I vitamine
Faced with the lost value of information that was traditionally produced by the press, audiences are now turning to social networks and interacting with the news in new ways. And, as a result, the low credibility of the Spanish media is negated by diversifying the sources for news information as people turn to their trusted gatekeeping “friends” who act as watchdogs of the fourth estate. For the moment this new relationship with social media does not mean a distancing from the news produced by professional journalists, but it does require that the media take steps to overcome the perceived loss in value of the information they produce
Video in the cybermedia: some certainties and many doubts
Video has become widespread in Spanish online newspapers in recent years. However, its adoption raises some questions and important challenges. This paper suggests some of the motivations that have driven its development and describes the most common types of news video content. Additionally, it underlines some doubts about the model of video inclusion that online newspapers have adopted and the actual capacity to capture the interest of the audience
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