Publications (69)
Spectral Calibration of the Fluorescence Telescopes of the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +403
We present a novel method to measure precisely the relative spectral response of the fluorescence telescopes of the Pierre Auger Observatory. We used a portable light source based…
Cosmological consequences of an inhomogeneous space-time
F. Canfora, A. Troisi
Astrophysical observations provide a picture of the universe as a 4-dim homogeneous and isotropic flat space-time dominated by an unknown form of dark energy. To achieve such a cos…
Muon Counting using Silicon Photomultipliers in the AMIGA detector of the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +422
AMIGA (Auger Muons and Infill for the Ground Array) is an upgrade of the Pierre Auger Observatory designed to extend its energy range of detection and to directly measure the muon…
Combined fit of spectrum and composition data as measured by the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +397
We present a combined fit of a simple astrophysical model of UHECR sources to both the energy spectrum and mass composition data measured by the Pierre Auger Observatory. The fit h…
Azimuthal asymmetry in the risetime of the surface detector signals of the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +436
The azimuthal asymmetry in the risetime of signals in Auger surface detector stations is a source of information on shower development. The azimuthal asymmetry is due to a combinat…
Arrival Directions of Cosmic Rays above 32 EeV from Phase One of the Pierre Auger Observatory
The Pierre Auger Collaboration, P. Abreu, M. Aglietta +372
A promising energy range to look for angular correlation between cosmic rays of extragalactic origin and their sources is at the highest energies, above few tens of EeV ($1\:{\rm E…
Extraction of the Muon Signals Recorded with the Surface Detector of the Pierre Auger Observatory Using Recurrent Neural Networks
The Pierre Auger Collaboration, A. Aab, P. Abreu +370
The Pierre Auger Observatory, at present the largest cosmic-ray observatory ever built, is instrumented with a ground array of 1600 water-Cherenkov detectors, known as the Surface…
Measurement of the fluctuations in the number of muons in extensive air showers with the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +365
We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuation…
Calibration of the Logarithmic-Periodic Dipole Antenna (LPDA) Radio Stations at the Pierre Auger Observatory using an Octocopter
The Pierre Auger Collaboration, A. Aab, P. Abreu +402
An in-situ calibration of a logarithmic periodic dipole antenna with a frequency coverage of 30 MHz to 80 MHz is performed. Such antennas are part of a radio station system used fo…
Search for Spatial Correlations of Neutrinos with Ultra-High-Energy Cosmic Rays
The ANTARES collaboration, A. Albert, S. Alves +1042
For several decades, the origin of ultra-high-energy cosmic rays (UHECRs) has been an unsolved question of high-energy astrophysics. One approach for solving this puzzle is to corr…
A targeted search for point sources of EeV photons with the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +397
Simultaneous measurements of air showers with the fluorescence and surface detectors of the Pierre Auger Observatory allow a sensitive search for EeV photon point sources. Several…
A new generation photodetector for astroparticle physics: the VSiPMT
G. Barbarino, F. C. T. Barbato, L. Campajola +8
The VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an innovative design we proposed for a revolutionary photon detector. The main idea is to replace the classical dynode chain of…
Some exact solutions with torsion in 5-D Einstein-Gauss-Bonnet gravity
F. Canfora, A. Giacomini, S. Willison
Exact solutions with torsion in Einstein-Gauss-Bonnet gravity are derived. These solutions have a cross product structure of two constant curvature manifolds. The equations of moti…
Measurement of the cosmic-ray energy spectrum above eV using the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +380
We report a measurement of the energy spectrum of cosmic rays for energies above eV based on 215,030 events recorded with zenith angles below . A k…
Multi-Messenger Physics with the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +390
An overview of the multi-messenger capabilities of the Pierre Auger Observatory is presented. The techniques and performance of searching for Ultra-High Energy neutrinos, photons a…
Search for High-energy Neutrinos from Binary Neutron Star Merger GW170817 with ANTARES, IceCube, and the Pierre Auger Observatory
A. Albert, M. Andre, M. Anghinolfi +1931
The Advanced LIGO and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gamma-ray burst (GRB) that followed the merg…
Deep-Learning based Reconstruction of the Shower Maximum using the Water-Cherenkov Detectors of the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +370
The atmospheric depth of the air shower maximum is an observable commonly used for the determination of the nuclear mass composition of ultra-high energy cosmic…
Trace anomaly and black holes evaporation
F. Canfora, G. Vilasi
A model is proposed to describe a transition from a Schwarzschild black hole of mass to a Schwarzschild black hole of mass . The basic equations are der…
Spin-1 gravitational waves
F. Canfora, G. Vilasi, P. Vitale
Gravitational fields invariant for a 2-dimensional Lie algebra of Killing fields [ X,Y] =Y, with Y of light type, are analyzed. The conditions for them to represent gravitational w…
Investigating Hadronic Interactions at Ultra-High Energies with the Pierre Auger Observatory
Isabel Goos, :, P. Abreu +374
The development of an extensive air shower depends not only on the nature of the primary ultra-high-energy cosmic ray but also on the properties of the hadronic interactions. For e…
Inferences on Mass Composition and Tests of Hadronic Interactions from 0.3 to 100 EeV using the water-Cherenkov Detectors of the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +403
We present a new method for probing the hadronic interaction models at ultra-high energy and extracting details about mass composition. This is done using the time profiles of the…
Vacuum solutions which cannot be written in diagonal form
F. Canfora, H. -J. Schmidt
A vacuum solution of the Einstein gravitational field equation is given that follows from a general ansatz but fails to follow from it if a certain symmetric matrix is assumed to b…
Features of the energy spectrum of cosmic rays above eV using the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +380
We report a measurement of the energy spectrum of cosmic rays above eV based on events. New results are presented: at about eV…
Indication of anisotropy in arrival directions of ultra-high-energy cosmic rays through comparison to the flux pattern of extragalactic gamma-ray sources
The Pierre Auger Collaboration, A. Aab, P. Abreu +390
A new analysis of the dataset from the Pierre Auger Observatory provides evidence for anisotropy in the arrival directions of ultra-high-energy cosmic rays on an intermediate angul…
The UV behavior of Gravity at Large N
F. Canfora
A first step in the analysis of the renormalizability of gravity at Large N is carried on. Suitable resummations of planar diagrams give rise to a theory in which there is only a f…
Spin-1 gravitational waves. Theoretical and experimental aspects
F. Canfora, L. Parisi, G. Vilasi
Exact solutions of Einstein field equations invariant for a non-Abelian 2-dimensional Lie algebra of Killing fields are described. Physical properties of these gravitational fields…
Cosmological implications of photon-flux upper limits at ultra-high energies in scenarios of Planckian-interacting massive particles for dark matter
The Pierre Auger Collaboration, P. Abreu, M. Aglietta +374
Using the data of the Pierre Auger Observatory, we report on a search for signatures that would be suggestive of super-heavy particles decaying in the Galactic halo. From the lack…
Testing Hadronic Interactions at Ultrahigh Energies with Air Showers Measured by the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +435
Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models with…
Observation of a Large-scale Anisotropy in the Arrival Directions of Cosmic Rays above eV
The Pierre Auger Collaboration, A. Aab, P. Abreu +404
Cosmic rays are atomic nuclei arriving from outer space that reach the highest energies observed in nature. Clues to their origin come from studying the distribution of their arriv…
A search for photons with energies above eV using hybrid data from the low-energy extensions of the Pierre Auger Observatory
The Pierre Auger Collaboration, P. Abreu, M. Aglietta +373
Ultra-high-energy photons with energies exceeding eV offer a wealth of connections to different aspects of cosmic-ray astrophysics as well as to gamma-ray and neutrino as…
Multi-resolution anisotropy studies of ultrahigh-energy cosmic rays detected at the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +400
We report a multi-resolution search for anisotropies in the arrival directions of cosmic rays detected at the Pierre Auger Observatory with local zenith angles up to and…
Observation of inclined EeV air showers with the radio detector of the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +392
With the Auger Engineering Radio Array (AERA) of the Pierre Auger Observatory, we have observed the radio emission from 561 extensive air showers with zenith angles between 60$^\ci…
Analytic topologically non-trivial solutions of the (3+1)-dimensional gauged Skyrme model and extended duality
L. Avilés, F. Canfora, N. Dimakis +1
We construct the first analytic examples of topologically non-trivial solutions of the (3+1)-dimensional gauged Skyrme model within a finite box in (3+1)-dimensional flat sp…
Some solutions with torsion in Chern-Simons gravity and observable effects
F. Canfora
It is shown that in all odd dimensional Chern-Simons theories states in which the torsion is non zero (but it can approach smoothly to zero outside suitable regions) do exist. Some…
The energy spectrum of cosmic rays beyond the turn-down around eV as measured with the surface detector of the Pierre Auger Observatory
The Pierre Auger Collaboration, P. Abreu, M. Aglietta +374
We present a measurement of the cosmic-ray spectrum above 100\,PeV using the part of the surface detector of the Pierre Auger Observatory that has a spacing of 750~m. An inflection…
A search for ultra high energy neutrinos from TXS 0506+056 using the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +364
Results of a search for ultra-high-energy neutrinos with the Pierre Auger Observatory from the direction of the blazar TXS 0506+056 are presented. They were obtained as part of the…
The Holographic Principle and the Early Universe
F. Canfora, G. Vilasi
A scenario is proposed in which the matter-antimatter asymmetry behaves like a seed for the inflationary phase of the universe. The mechanism which makes this scenario plausible is…
Design and implementation of the AMIGA embedded system for data acquisition
The Pierre Auger Collaboration, A. Aab, P. Abreu +383
The Auger Muon Infill Ground Array (AMIGA) is part of the AugerPrime upgrade of the Pierre Auger Observatory. It consists of particle counters buried 2.3 m underground next to the…
Testing effects of Lorentz invariance violation in the propagation of astroparticles with the Pierre Auger Observatory
The Pierre Auger Collaboration, P. Abreu, M. Aglietta +374
Lorentz invariance violation (LIV) is often described by dispersion relations of the form with delta different based on particle type , with…
Calibration of the underground muon detector of the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +370
To obtain direct measurements of the muon content of extensive air showers with energy above eV, the Pierre Auger Observatory is currently being equipped with an underg…
Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrum
The Pierre Auger Collaboration, A. Aab, P. Abreu +423
We report a first measurement for ultra-high energy cosmic rays of the correlation between the depth of shower maximum and the signal in the water Cherenkov stations of air-showers…
Cosmic-ray anisotropies in right ascension measured by the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +373
We present measurements of the large-scale cosmic-ray anisotropies in right ascension, using data collected by the surface detector array of the Pierre Auger Observatory over more…
PP-waves, Israel's Matching conditions, Brane-world scenarios and BPS states in gravity
F. Canfora, G. Vilasi
The matching between two 4-dimensional PP-waves is discussed by using Israel's matching conditions. Physical consequences on the dynamics of (cosmic) strings are analyzed. The exte…
Analytic Studies of Static and Transport Properties of (Gauged) Skyrmions
F. Canfora, N. Dimakis, A. Paliathanasis
We study static and transport properties of Skyrmions living within a finite spatial volume in a flat (3+1)-dimensional spacetime. In particular, we derive an explicit analytic exp…
Probing the origin of ultra-high-energy cosmic rays with neutrinos in the EeV energy range using the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +389
Neutrinos with energies above eV are detectable with the Surface Detector Array of the Pierre Auger Observatory. The identification is efficiently performed for neutrinos…
On the effects of conformal degrees of freedom inside a neutron star
F. Canfora, A. Giacomini, S. Willison
In this paper a neutron star with an inner core which undergoes a phase transition, which is characterized by conformal degrees of freedom on the phase boundary, is considered. Typ…
The FRAM robotic telescope for atmospheric monitoring at the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +377
FRAM (F/Photometric Robotic Atmospheric Monitor) is a robotic telescope operated at the Pierre Auger Observatory in Argentina for the purposes of atmospheric monitoring using stell…
Does the Holographic Principle determine the Gravitational Interaction?
F. Canfora, G. Vilasi
It is likely that the holographic principle will be a consequence of the would be theory of quantum gravity. Thus, it is interesting to try to go in the opposite direction: can the…
Integrability and chemical potential in the (3+1)-dimensional Skyrme model
P. D. Alvarez, F. Canfora, N. Dimakis +1
Using a remarkable mapping from the original (3+1)dimensional Skyrme model to the Sine-Gordon model, we construct the first analytic examples of Skyrmions as well as of Skyrmions--…
A Large N expansion for Gravity
F. Canfora
A Large N expansion for gravity is proposed. The scheme is based on the splitting of the Einstein-Hilbert action into the BF topological action plus a constraint. The method also a…
Reconstruction of Events Recorded with the Surface Detector of the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +378
Cosmic rays arriving at Earth collide with the upper parts of the atmosphere, thereby inducing extensive air showers. When secondary particles from the cascade arrive at the ground…
Ultrahigh-energy neutrino follow-up of Gravitational Wave events GW150914 and GW151226 with the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +410
On September 14, 2015 the Advanced LIGO detectors observed their first gravitational-wave (GW) transient GW150914. This was followed by a second GW event observed on December 26, 2…
Limits on point-like sources of ultra-high-energy neutrinos with the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +389
With the Surface Detector array (SD) of the Pierre Auger Observatory we can detect neutrinos with energy between eV and eV from point-like sources across the…
Measurement of the average shape of longitudinal profiles of cosmic-ray air showers at the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +385
The profile of the longitudinal development of showers produced by ultra-high energy cosmic rays carries information related to the interaction properties of the primary particles…
Search for photons with energies above 10 eV using the hybrid detector of the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +397
A search for ultra-high energy photons with energies above 1 EeV is performed using nine years of data collected by the Pierre Auger Observatory in hybrid operation mode. An unprec…
Search for ultrarelativistic magnetic monopoles with the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +411
We present a search for ultra-relativistic magnetic monopoles with the Pierre Auger Observatory. Such particles, possibly a relic of phase transitions in the early universe, would…
Cooking pasta with Lie groups
S. L. Cacciatori, F. Canfora, M. Lagos +2
We extend the (gauged) Skyrme model to the case in which the global isospin group (which usually is taken to be ) is a generic compact connected Lie group . We analyze th…
Studies on the response of a water-Cherenkov detector of the Pierre Auger Observatory to atmospheric muons using an RPC hodoscope
The Pierre Auger Collaboration, A. Aab, P. Abreu +375
Extensive air showers, originating from ultra-high energy cosmic rays, have been successfully measured through the use of arrays of water-Cherenkov detectors (WCDs). Sophisticated…
The Pierre Auger Observatory: Contributions to the 36th International Cosmic Ray Conference (ICRC 2019)
The Pierre Auger Collaboration, A. Aab, P. Abreu +383
Contributions of the Pierre Auger Collaboration to the 36th International Cosmic Ray Conference (ICRC 2019), 24 July - 1 August 2019, Madison, Wisconsin, USA.
Data-driven estimation of the invisible energy of cosmic ray showers with the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +389
The determination of the primary energy of extensive air showers using the fluorescence detection technique requires an estimation of the energy carried away by particles that do n…
A note on Tachyon dynamics
F. Canfora
A suitable splitting of tachyon field equation is able to disclose non trivial properties of Born-Infeld (some known, some unexpected) and Polyakov actions; the tachyon equation al…
Design, upgrade and characterization of the silicon photomultiplier front-end for the AMIGA detector at the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +357
AMIGA (Auger Muons and Infill for the Ground Array) is an upgrade of the Pierre Auger Observatory to complement the study of ultra-high-energy cosmic rays (UHECR) by measuring the…
Large-scale cosmic-ray anisotropies above 4 EeV measured by the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +374
We present a detailed study of the large-scale anisotropies of cosmic rays with energies above 4 EeV measured using the Pierre Auger Observatory. For the energy bins [4,8] EeV and…
Limits to gauge coupling in the dark sector set by the non-observation of instanton-induced decay of Super-Heavy Dark Matter in the Pierre Auger Observatory data
The Pierre Auger Collaboration, P. Abreu, M. Aglietta +374
Instantons, which are non-perturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give…
Nonlinear gravitational waves and their polarization
F. Canfora, G. Vilasi, P. Vitale
Vacuum gravitational fields invariant for a non Abelian Lie algebra generated by two Killing fields whose commutator is light-like are analyzed. It is shown that they represent non…
The Pierre Auger Observatory: Contributions to the 35th International Cosmic Ray Conference (ICRC 2017)
The Pierre Auger Collaboration, A. Aab, P. Abreu +394
Contributions of the Pierre Auger Collaboration to the 35th International Cosmic Ray Conference (ICRC 2017), 12-20 July 2017, Bexco, Busan, Korea.
Spin-1 gravitational waves and their natural sources
F. Canfora, G. Vilasi
Non-vacuum exact gravitational waves invariant for a non Abelian two-dimensional Lie algebra generated by two Killing fields whose commutator is of light type, are described. The p…
Search for magnetically-induced signatures in the arrival directions of ultra-high-energy cosmic rays measured at the Pierre Auger Observatory
The Pierre Auger Collaboration, A. Aab, P. Abreu +372
We search for signals of magnetically-induced effects in the arrival directions of ultra-high-energy cosmic rays detected at the Pierre Auger Observatory. We apply two different me…
Regge theory and statistical mechanics
F. Canfora, L. Parisi, G. Vilasi
An interesting connection between the Regge theory of scattering, the Veneziano amplitude, the Lee-Yang theorems in statistical mechanics and nonextensive Renyi entropy is addresse…