Repozitorij Univerze v Novi Gorici

Iskanje po repozitoriju
A+ | A- | Pomoč | SLO | ENG

Iskalni niz: išči po
išči po
išči po
išči po
* po starem in bolonjskem študiju

Opcije:
  Ponastavi


1 - 7 / 7
Na začetekNa prejšnjo stran1Na naslednjo stranNa konec
1.
Update of the neutrino and photon limits from the Pierre Auger Observatory
Marko Zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Carla Bleve, 2015, objavljeni znanstveni prispevek na konferenci

Opis: Ultra-high energy neutrinos and photons, with energies above 1 EeV and 10 EeV respectively, can be detected with the Surface Detector array (SD) of the Pierre Auger Observatory. Downward- going neutrinos of all flavours interacting in the atmosphere at zenith angles θ > 60◦, upward-going tau neutrinos (“Earth- skimming”), as well as photons in the zenith range 30◦ − 60◦ can be identified through the broad time-structure of the signals expected to be induced in the SD stations. An additional signature for photon-induced air showers is the steeper lateral distribution of secondary particles at ground with respect to the nucleonic showers. Stringent limits are set to the diffuse flux of ultra-high energy (UHE) neutrinos and photons, using data collected between 2004 and mid-2013, under the hypothesis of an E[sup]−2 spectrum for signal primaries.
Najdeno v: ključnih besedah
Povzetek najdenega: ...Ultra-high energy neutrinos and photons, with energies above 1 EeV and 10...
Ključne besede: ultra-high energy neutrinos, ultra-high energy photons, cosmic rays, elemental composition, Pierre Auger Observatory
Objavljeno: 03.03.2016; Ogledov: 2764; Prenosov: 177
.pdf Polno besedilo (398,21 KB)

2.
3.
Multi-Messenger Physics With the Pierre Auger Observatory
Karl-Heinz Kampert, Andrej Filipčič, Gašper Kukec Mezek, Samo Stanič, Marta Trini, Serguei Vorobiov, Lili Yang, Danilo Zavrtanik, Marko Zavrtanik, Lukas Zehrer, 2019, izvirni znanstveni članek

Najdeno v: ključnih besedah
Povzetek najdenega: ...Pierre Auger Observatory, ultra-high energy cosmic rays, photons, neutrinos, protons, multi-messenger physics and astrophysics...
Ključne besede: Pierre Auger Observatory, ultra-high energy cosmic rays, photons, neutrinos, protons, multi-messenger physics and astrophysics
Objavljeno: 06.05.2019; Ogledov: 1428; Prenosov: 66
.pdf Polno besedilo (2,46 MB)

4.
Generation and applications of extreme-ultraviolet vortices
Carlos Hernández-García, Jorge Vieira, Jose T. Mendonça, Laura Rego, Julio San Román, Luis Plaja, Primož Rebernik Ribič, David Gauthier, Antonio Picón, 2017, izvirni znanstveni članek

Najdeno v: ključnih besedah
Povzetek najdenega: ...XUV/X-ray vortices, orbital angular momentum of photons, high-harmonic generation, free-electron lasers, plasma physics...
Ključne besede: XUV/X-ray vortices, orbital angular momentum of photons, high-harmonic generation, free-electron lasers, plasma physics
Objavljeno: 13.01.2020; Ogledov: 1249; Prenosov: 5
Gradivo ima več datotek! Več...

5.
Constraints on the diffuse photon flux with energies above 10^18 eV using the surface detector of the Telescope Array experiment
J. P. Lundquist, R.U. Abbasi, 2018, izvirni znanstveni članek

Opis: We present the results of the search for ultra-high-energy photons with nine years of data from the Telescope Array surface detector. A multivariate classifier is built upon 16 reconstructed parameters of the extensive air shower. These parameters are related to the curvature and the width of the shower front, the steepness of the lateral distribution function, and the timing parameters of the waveforms sensitive to the shower muon content. A total number of two photon candidates found in the search is fully compatible with the expected background. The 95% CL limits on the diffuse flux of the photons with energies greater than 10^18.0, 10^18.5, 10^19.0, 10^19.5 and 10^20.0 eV are set at the level of 0.067, 0.012, 0.0036, 0.0013, correspondingly.
Najdeno v: ključnih besedah
Povzetek najdenega: ...the results of the search for ultra-high-energy photons with nine years of data from the...
Ključne besede: Ultra-high-energy photons, Telescope array experiment, Extensive air showers
Objavljeno: 30.04.2020; Ogledov: 1075; Prenosov: 0
.pdf Polno besedilo (1,33 MB)

6.
Extrapolating FR-0 radio galaxy source properties from propagation of multi-messenger ultra-high energy cosmic rays
Chiara Righi, Giacomo Bonnoli, Fabrizio Tavecchio, Paolo Da Vela, Anita Reimer, Margot Boughelilba, Serguei Vorobiov, Lukas Merten, Jon Paul Lundquist, 2021, objavljeni znanstveni prispevek na konferenci

Opis: Recently, it has been shown that relatively low luminosity Fanaroff-Riley type 0 (FR-0) radio galaxies are a good candidate source class for a predominant fraction of cosmic rays (CR) accelerated to ultra-high energies (UHE, E>10[sup]18 eV). FR-0s can potentially provide a significant fraction of the UHECR energy density as they are much more numerous in the local universe than more energetic radio galaxies such as FR-1s or FR-2s (up to a factor of ∼5 with z≤0.05 compared to FR-1s). In the present work, UHECR mass composition and energy spectra at the FR-0 sources are estimated by fitting simulation results to the published Pierre Auger Observatory data. This fitting is done using a simulated isotropic sky distribution extrapolated from the measured FR-0 galaxy properties and propagating CRs in plausible extragalactic magnetic field configurations using the CRPropa3 framework. In addition, we present estimates of the fluxes of secondary photons and neutrinos created in UHECR interactions with cosmic photon backgrounds during CR propagation. With this approach, we aim to investigate the properties of the sources with the help of observational multi-messenger data.
Najdeno v: ključnih besedah
Povzetek najdenega: ...present estimates of the fluxes of secondary photons and neutrinos created in UHECR interactions with...
Ključne besede: jetted active galaxies, FR-0 radiogalaxies, ultra-high energy cosmic rays, extragalactic magnetic fields, UHECR propagation, UHECR interactions, cosmogenic photons, cosmogenic neutrinos
Objavljeno: 16.08.2021; Ogledov: 151; Prenosov: 0
.pdf Polno besedilo (2,04 MB)

7.
Application of machine learning techniques for cosmic ray event classification and implementation of a real-time ultra-high energy photon search with the surface detector of the Pierre Auger Observatory
Lukas Zehrer, 2021, doktorska disertacija

Opis: Despite their discovery already more than a century ago, Cosmic Rays (CRs) still did not divulge all their properties yet. Theories about the origin of ultra-high energy (UHE, > 10^18 eV) CRs predict accompanying primary photons. The existence of UHE photons can be investigated with the world’s largest ground-based experiment for detection of CR-induced extensive air showers (EAS), the Pierre Auger Observatory, which offers an unprecedented exposure to rare UHE cosmic particles. The discovery of photons in the UHE regime would open a new observational window to the Universe, improve our understanding of the origin of CRs, and potentially uncloak new physics beyond the standard model. The novelty of the presented work is the development of a "real-time" photon candidate event stream to a global network of observatories, the Astrophysical Multimessenger Observatory Network (AMON). The stream classifies CR events observed by the Auger surface detector (SD) array as regards their probability to be photon nominees, by feeding to advanced machine learning (ML) methods observational air shower parameters of individual CR events combined in a multivariate analysis (MVA). The described straightforward classification procedure further increases the Pierre Auger Observatory’s endeavour to contribute to the global effort of multi-messenger (MM) studies of the highest energy astrophysical phenomena, by supplying AMON partner observatories the possibility to follow-up detected UHE events, live or in their archival data.
Najdeno v: ključnih besedah
Povzetek najdenega: ...> 10^18 eV) CRs predict accompanying primary photons. The existence of UHE photons can be...
Ključne besede: astroparticle physics, ultra-high energy cosmic rays, ultra-high energy photons, extensive air showers, Pierre Auger Observatory, multi-messenger, AMON, machine learning, multivariate analysis, dissertations
Objavljeno: 27.10.2021; Ogledov: 2; Prenosov: 0
URL Polno besedilo (0,00 KB)
Gradivo ima več datotek! Več...

Iskanje izvedeno v 0 sek.
Na vrh