On the potential of Cherenkov Telescope Arrays and KM3 Neutrino Telescopes for the detection of extended sources

We discuss the discovery potential of extended very-high-energy (VHE) neutrino sources by the future KM3 Neutrino Telescope (KM3NeT) in the context of the constraining power of the Cherenkov Telescope Array (CTA), designed for deep surveys of the sky in VHE gamma rays. The study is based on a comparative analysis of sensitivities of KM3NeT and CTA. We show that a minimum gamma-ray energy flux of E^2{\phi}_{\gamma}(10 TeV) > 1x10^{-12} TeV cm^{-2} s^{-1} is required to identify a possible neutrino counterpart with a 3{\sigma} significance and 10 years of KM3NeT observations with upgoing muons, if the source has an angular size of R_{src} = 0.1 deg and emits gamma rays with an E^{-2} energy spectrum through a full hadronic mechanism. This minimum gamma-ray flux is increased to the level of E^2{\phi}_{\gamma}(10 TeV) > 2x10^{-11} TeV cm^{-2} s^{-1} in case of sources with radial extension of R_{src} = 2.0 deg. The analysis methods are applied to the supernova remnant RX J1713.7-3946 and the Galactic Center Ridge, as well as to the recent HAWC catalog of multi-TeV gamma-ray sources.Comment: 15 pages, 7 figure

Search for high-energy neutrinos from GRB130427A with the ANTARES neutrino telescope

ANTARES is the first deep under-sea high-energy astrophysical neutrino telescope, in operation since 2008, in the Northern Hemisphere. In the light of a multi-messenger approach, one of the most ever intense (photon fluence F? 10-3 erg/cm2) and close (redshift z = 0.34) transient ?-source, GRB130427A, is considered in the ANTARES physics program for a co-incident search for photons and high-energy neutrinos. The first time-dependent analysis on GRBs neutrino emissions has been performed for this source: Konus-Wind parameters of the ? time-dependent spectrum are used to predict the expected neutrino flux from each peak of the burst, through the numerical calculation code NeuCosmA. An extended maximum likelihood ratio search is performed in order to maximize the discovery probability of prompt neutrinos from the burst: at the end, ANTARES sensitivity to this source is evaluated to be E2?v ~ 1 -10 GeV/cm2 in the energy range from 2 x 105 GeV to 2 x 107 GeV

Detection prospects for low-energy neutrinos from collisionally heated GRBs with current and future neutrino telescopes

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On the mass and wind luminosity of young Galactic open clusters in Gaia DR2

Context. Star clusters constitute a relevant part of the stellar population in our Galaxy. The feedback processes they exert on the interstellar medium impact multiple physical processes, from the chemical to the dynamical evolution of the Galaxy. In addition, young and massive stellar clusters might act as efficient particle accelerators, possibly contributing to the production of cosmic rays. Aims. We aim at evaluating the wind luminosity driven by the young (< 30 Myr) Galactic open stellar clusters observed by the Gaia space mission, which is crucial to determine the energy channeled into accelerated particles. Methods. To this extent, we develop a method relying on the number, magnitude and line-of-sight extinction of the stars observed per cluster. Assuming that the stellar mass function follows a Kroupa mass distribution, and accounting for the maximum stellar mass allowed by both the parent cluster age and mass, we conservatively estimate the mass and wind luminosity of 387 local clusters within the second data release of Gaia. Results. We compare the results of our computation with recent estimations of young cluster masses. With respect to these, we provide a sample three times more abundant, particularly above a few thousand solar masses, which is of the utmost relevance for predicting the gamma-ray emission resulting from the interaction of accelerated particles. In fact, the cluster wind luminosity distribution we obtain is found to extend up to 3 x 10^38 erg/s, a promising feature in terms of potential particle acceleration scenarios.Comment: 11 pages, 16 figures, comments are welcom

Optimization of an analytical method based on SPME-Arrow and chemometrics for the characterization of the aroma profile of commercial bread

A SPME-Arrow GC-MS approach, coupled with chemometrics, was used to thoroughly investigate the impact of different types of yeast (sourdough, bear's yeast and a mixture of both) and their respective leaving time (one, three and five hours) on VOCs of commercial bread samples. This aspect is of paramount importance for the baking industry to adjust recipe modifications and production parameters, as well as to meet consumer needs in formulating new products. A deep learning approach, PARADISe (PARAFAC2-based deconvolution and identification system), was used to analyse the obtained chromatograms in an untargeted manner. In particular, PARADISe, was able to perform a fast deconvolution of the chromatographic peaks directly from raw chromatographic data to allow a putatively identification of 66 volatile organic compounds, including alcohols, esters, carboxylic acids, ketones, aldehydes. Finally, Principal Component Analysis, applied on the areas of the resolved compounds, showed that bread samples differentiate according to their recipe and highlighted the most relevant volatile compounds responsible for the observed differences

TeV emission from Gamma Ray Bursts, checking the hadronic model

Gamma-Ray Bursts (GRBs) are the most luminous explosions in the Universe. Their luminous prompt emission makes them detectable from cosmological distances. Most GRBs have been detected below a few MeV, however at least a hundred GRBs have been detected at high (0.1 GeV) energies and observed up to tens of GeV with the Fermi Large Area Telescope (LAT). Some GRBs have been observed at (0.1–1) TeV by ground-based imaging atmospheric Cherenkov telescopes. To date, the high energy emission mechanism is not understood. In this paper we review the possible leptonic and hadronic mechanisms capable of producing the ∼ TeV emission detected in GRBs. In paricular we concentrate on the hadronic origin of this radiation component and discuss in detail the numerical simulation elaborated to reproduce the observed sub-TeV observations of GRB190114C

Neutrino predictions from choked Gamma-Ray Bursts and comparison with the observed cosmic diffuse neutrino flux

The strong constraints from the Fermi-LAT data on the isotropic gamma-ray background suggest that the neutrinos observed by IceCube might possibly come from sources that are hidden to gamma-ray observations. A possibility emerged in recent years is that neutrinos may come from jets of collapsing massive stars which fail to break out of the stellar envelope, and for this reason they are known as choked jets, or choked Gamma-Ray Bursts (GRBs). We here show our predictions of neutrino flux and spectrum expected from these sources, focusing on Type II SNe, through detailed calculations of pγ interactions and accounting for all the neutrino production channels and scattering angles. We provide predictions of expected event rates for ANTARES, IceCube, and the next generation neutrino telescope KM3NeT.We also compute the contribution of the choked GRB population to the diffuse astrophysical neutrino flux, thus providing constraints on the local rate of this source population as to reproduce the observed neutrino flux

Emotion and Sentiment in Social and Expressive Media: Introduction to the special issue

This is the author’s version of a work that was accepted for publication in Information Processing and Management . Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Information Processing and Management 52 (2016) 1–4. DOI 10.1016/j.ipm.2015.11.002[EN] Social and expressive media represent a challenge and a push forward for research on emotion and sentiment analysis. The advent of social media has brought about new paradigms of interaction that foster first-person engagement and crowdsourced contents: the subjective dimension moves to the foreground, opening the way to the emergence of an affective component within a dynamic corpus of digitized contents created and enriched by the users. Expressive media, which play a key role in fields related to creativity, such as figurative arts, music or drama, gather multimedia contents into online social environments, by joining the social dimension with the aims of artistic creation and self-expression. Artistic creation and performance seem to be a very interesting testbed for cross-validating and possibly integrating approaches, models and tools for automatically analyzing emotion and sentiment. In fact, in such contexts the social and affective dimensions (emotions and feelings) naturally emerge (Silvia, 2005), think for instance of the visitors’ feedback to a real or virtual art exhibition, or of the audience–performance interaction (...) In light of these considerations, this special issue focuses on the presentation and discussion of a set of novel computational approaches to the analysis of emotion and sentiment in social and expressive media.Paolo Rosso has been partially funded by the WIQ–EI IRSES project (Grant no. 269180) within the EC FP7 Marie Curie People Framework and by the DIANA-APPLICATIONS – Finding Hidden Knowledge in Texts: Applications project (TIN2012-38603-C02-01). The last phase of the work of Viviana Patti was carried out at the Universitat Politècnica de València in the framework of a three-month fellowship of the University of Turin within the World Wide Style (WWS) Program, Second Edition, co-funded by Fondazione CRT .Rosso, P.; Bosco, C.; Damiano, R.; Patti, V.; Cambria, E. (2016). Emotion and Sentiment in Social and Expressive Media: Introduction to the special issue. Information Processing and Management. 52(1):1-4. https://doi.org/10.1016/j.ipm.2015.11.002S1452