19 research outputs found

    Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

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    The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E>Eth=5.5×1019E>E_{th}=5.5\times 10^{19} eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E>EthE>E_{th} are heavy nuclei with charge ZZ, the proton component of the sources should lead to excesses in the same regions at energies E/ZE/Z. We here report the lack of anisotropies in these directions at energies above Eth/ZE_{th}/Z (for illustrative values of Z=6, 13, 26Z=6,\ 13,\ 26). If the anisotropies above EthE_{th} are due to nuclei with charge ZZ, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies

    Advanced functionality for radio analysis in the Offline software framework of the Pierre Auger Observatory

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    The advent of the Auger Engineering Radio Array (AERA) necessitates the development of a powerful framework for the analysis of radio measurements of cosmic ray air showers. As AERA performs "radio-hybrid" measurements of air shower radio emission in coincidence with the surface particle detectors and fluorescence telescopes of the Pierre Auger Observatory, the radio analysis functionality had to be incorporated in the existing hybrid analysis solutions for fluoresence and surface detector data. This goal has been achieved in a natural way by extending the existing Auger Offline software framework with radio functionality. In this article, we lay out the design, highlights and features of the radio extension implemented in the Auger Offline framework. Its functionality has achieved a high degree of sophistication and offers advanced features such as vectorial reconstruction of the electric field, advanced signal processing algorithms, a transparent and efficient handling of FFTs, a very detailed simulation of detector effects, and the read-in of multiple data formats including data from various radio simulation codes. The source code of this radio functionality can be made available to interested parties on request.Comment: accepted for publication in NIM A, 13 pages, minor corrections to author list and references in v

    Search for First Harmonic Modulation in the Right Ascension Distribution of Cosmic Rays Detected at the Pierre Auger Observatory

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    We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5×10172.5\times 10^{17} eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L.C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.Comment: 28 pages, 11 figure

    Galactic Gamma-Ray Diffuse Emission at TeV energies with HAWC Data

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    The Galactic gamma-ray diffuse emission (GDE) is emitted by cosmic rays (CRs), ultra-relativistic protons and electrons, interacting with gas and electromagnetic radiation fields in the interstellar medium. Here we present the analysis of TeV diffuse emission from a region of the Galactic Plane over the range in longitude of l[43,73]l\in[43^\circ,73^\circ], using data collected with the High Altitude Water Cherenkov (HAWC) detector. Spectral, longitudinal and latitudinal distributions of the TeV diffuse emission are shown. The radiation spectrum is compatible with the spectrum of the emission arising from a CR population with an "index" similar to that of the observed CRs. When comparing with the \texttt{DRAGON} \textit{base model}, the HAWC GDE flux is higher by about a factor of two. Unresolved sources such as pulsar wind nebulae and TeV halos could explain the excess emission. Finally, deviations of the Galactic CR flux from the locally measured CR flux may additionally explain the difference between the predicted and measured diffuse fluxes

    An explanation of the muon puzzle of ultrahigh-energy cosmic rays and the role of the Forward Physics Facility for model improvement

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    We investigate the observed muon deficit in air shower simulations when compared to ultrahigh-energy cosmic ray (UHECR) data. Based upon the observed enhancement of strangeness production in high-energy hadronic collisions reported by the ALICE Collaboration, the concomitant πK\pi \leftrightarrow K swap is considered as the keystone to resolve the muon anomaly through its corresponding impact on the shower development. We construct a toy model in terms of the πK\pi \leftrightarrow K swapping probability FsF_s. We present a parametrization of FsF_s in terms of the pseudorapidity that can accommodate the UHECR data. Looking to the future, we explore potential strategies for model improvement using the massive amounts of data to be collected by LHC neutrino detectors, such as FASERν\nu and experiments at the Forward Physics Facility. We calculate the corresponding sensitivity to FsF_s and show that these experiments will be able to probe the model phase space

    Exploration for Triatoma virus (TrV) infection in laboratory-reared triatomines of Latin America: a collaborative study

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    Triatoma virus (TrV) is a small, non-enveloped virus that has a +ssRNA genome and is currently classified under the Cripavirus genus of the Dicistroviridae family. TrV infects haematophagous triatomine insects (Hemiptera: Reduviidae), which are vectors of American Trypanosomiasis (Chagas disease). TrV can be transmitted through the horizontal fecal-oral route, and its infection causes either deleterious sublethal effects or even death of laboratory insect colonies. Various species of triatomines from different regions of Latin America are currently being reared in research laboratories, with little or no awareness of the presence of TrV; therefore, any biological conclusion drawn from experiments on insects infected with this virus is inherently affected by the side effects of its infection. In this study, we developed a mathematical model to estimate the sample size required for detecting a TrV infection. We applied this model to screen the infection in feces of triatomines belonging to insectaries from 13 Latin American countries, carrying out the identification of TrV by using reverse transcriptase PCR. TrV was detected in samples coming from Argentina, which is the country where several years ago the virus was first isolated from Triatoma infestans (Hemiptera: Reduviidae). Interestingly, several colonies from Brazil were also found infected with the virus. This positive result widens the TrV?s host range to a total of 14 triatomine species. Our findings suggest that many triatomine species distributed over a large region of South America may be naturally infected with TrV.Fil: Marti, Gerardo Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Estudios Parasitologicos y de Vectores. Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Centro de Estudios Parasitologicos y de Vectores; ArgentinaFil: Echeverria, Maria Gabriela. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Susevich, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Estudios Parasitologicos y de Vectores. Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Centro de Estudios Parasitologicos y de Vectores; ArgentinaFil: Ceccarelli, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Estudios Parasitologicos y de Vectores. Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Centro de Estudios Parasitologicos y de Vectores; ArgentinaFil: Balsalobre, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Estudios Parasitologicos y de Vectores. Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Centro de Estudios Parasitologicos y de Vectores; ArgentinaFil: Canale, Delmi Margarita. Centro de Referencia de Vectores, Coordinación Nacional de Control de Vectores, Pabellón Rawson-Hospital Colonia; ArgentinaFil: Stariolo, Raúl Luis. Centro de Referencia de Vectores, Coordinación Nacional de Control de Vectores, Pabellón Rawson-Hospital Colonia; ArgentinaFil: Guérin, Diego M. A.. Universidad del País Vasco; España. Consejo Superior de Investigaciones Cientificas; España. Universidad Politécnica de Valencia; EspañaFil: González Cifuentes, Nadia L.. Universidad de Los Andes; ColombiaFil: Guhl, Felipe. Universidad de Los Andes; ColombiaFil: Bacigalupo, Antonella. Universidad de Chile; ChileFil: Cattan, Pedro E.. Universidad de Chile; ChileFil: Garcıa, Alejandro. Secretaria Regional Ministerial de Salud de Coquimbo; ChileFil: Villacis, Anita G.. Pontificia Universidad Catolica del Ecuador; EcuadorFil: Grijalva, Mario J.. Pontificia Universidad Catolica del Ecuador; Ecuador. Ohio University; Estados UnidosFil: Solorzano, Elizabeth. Universidad de San Carlos; GuatemalaFil: Monroy, Carlota. Universidad de San Carlos; GuatemalaFil: Espinoza Blanco, Yrma. Universidad Nacional Mayor de San Marcos; PerúFil: Cordova Benzaquen, Eleazar. Universidad Nacional San Agustín de Arequipa; PerúFil: Ruelas llerena, Nancy. Universidad Nacional San Agustín de Arequipa; PerúFil: Guzmán loayza, Miriam. Dirección Regional de Salud Moquegua; PerúFil: Caceres, Abraham G.. Universidad Nacional Mayor de San Marcos; PerúFil: Vences Blanco, Mauro O.. Universidad Nacional Autónoma de México; MéxicoFil: Salazar Schettino, Paz María. Universidad Nacional Autónoma de México; MéxicoFil: Martínez Martínez, Ignacio. Universidad Nacional Autónoma de México; MéxicoFil: Espinoza Gutiérrez, Bertha. Universidad Nacional Autónoma de México; MéxicoFil: Mojoli, Andrés. Centro para el Desarrollo de la Investigación Científica. Asunción; ParaguayFil: Rojas de Arias, Antonieta. Centro para el Desarrollo de la Investigación Científica. Asunción; ParaguayFil: Feliciangeli, M. Dora. Universidad de Carabobo Maracay; VenezuelaFil: Rivera Mendoza, Pedro. Fundación para el Desarrollo; NicaraguaFil: Rozas Dennis, Gabriela Susana. Universidad Nacional del Sur; ArgentinaFil: Sánchez Eugenia, Rubén. Unidad de Biofísica; EspañaFil: Aguirre, Jon. Unidad de Biofísica; España. Fundación Biofísica Bizkaia; EspañaFil: Viguera, Ana R.. Unidad de Biofísica; EspañaFil: Hernádez Suárez, Carlos M.. Universidad de Colima; México. Unidad Monterrey; MéxicoFil: Vilchez, Susana. Universidad de Granada; EspañaFil: Osuna, Antonio. Universidad de Granada; EspañaFil: Gorla, David Eladio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de la Rioja. - Secretaria de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: Mougabure Cueto, Gastón Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación de Plagas e Insecticidas; ArgentinaFil: Esteban, Lidia. Universidad Industrial Santander; ColombiaFil: Angulo, Vıctor M.. Universidad Industrial Santander; ColombiaFil: Querido, Jailson F. B. Unidad de Biofísica; España. Fundación Biofísica Bizkaia; España. Universidad Nova de Lisboa; PortugalFil: Silva, Marcelo S.. Universidad Nova de Lisboa; PortugalFil: Marques, Tatiane. Universidade Federal do Triangulo Mineiro; BrasilFil: Anhe, Ana Carolina B. M.. Universidade Federal do Triangulo Mineiro; BrasilFil: Gomez Hernandez, Cesar. Universidade Federal do Triangulo Mineiro; BrasilFil: Ramirez, Luis E.. Universidade Federal do Triangulo Mineiro; BrasilFil: Rabinovich, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Estudios Parasitologicos y de Vectores. Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Centro de Estudios Parasitologicos y de Vectores; ArgentinaFil: Diotaiuti, Liléia. Centro de Pesquisas Rene Rachou-FIOCRUZ; BrasilFil: Guerin Aguilar , Diego Marcelo. Universidad del País Vasco; España. Unidad de Biofísica; España. Fundación Biofísica Bizkaia; Españ
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