11 documents found, page 1 of 2
Search for correlations between the arrival directions of IceCube neutrino even...
IceCube, Pierre Auger, Telescope Array collaboration (870 authors); Abreu, P.; Andringa, S.; Assis, P.; Blanco, A.; Cazon, L.; Conceicao, R.; Diogo, F.This paper presents the results of different searches for correlations between very high-energy neutrino candidates detected by IceCube and the highest-energy cosmic rays measured by the Pierre Auger Observatory and the Telescope Array. We first consider samples of cascade neutrino events and of high-energy neutrino-induced muon tracks, which provided evidence for a neutrino flux of astrophysical origin, and st...
Muon Array with RPCs for Tagging Air showers (MARTA)
Sarmento, Raul et al. (42 authors); Abreu, Pedro; Andringa Dias, Sofia; Assis, Pedro; Castro, Alberto Blanco; Brogueira, Pedro; Carolino, N.We discuss the concept of an array with Resistive Plate Chambers (RPC) for muon detection in ultra-high energy cosmic ray (UHECR) experiments. RPC have been used in particle physics experiments due to their fast timing properties and spatial resolution. The operation of a ground array detector poses challenging demands, as the RPC must operate remotely under extreme en- vironments, with limited power and minima...
Highlights from the Pierre Auger Observatory
Pierre Auger collaboration (496 authors); Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.The Pierre Auger Observatory is the world’s largest cosmic ray observatory. Our current exposure reaches nearly 40,000 km$^{2}$sr and provides us with an unprecedented quality data set. The performance and stability of the detectors and their enhancements are described. Data analyses have led to a number of major breakthroughs. Among these, we discuss the energy spectrum and the searches for large-scale anisotr...
Depth of maximum of air-shower profiles at the Pierre Auger Observatory. II. Co...
Pierre Auger collaboration (485 authors); Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.Using the data taken at the Pierre Auger Observatory between December 2004 and December 2012, we have examined the implications of the distributions of depths of atmospheric shower maximum (Xmax), using a hybrid technique, for composition and hadronic interaction models. We do this by fitting the distributions with predictions from a variety of hadronic interaction models for variations in the composition of th...
Electroweak Measurements in Electron-Positron Collisions at W-Boson-Pair Energi...
ALEPH, DELPHI, L3, OPAL, LEP Electroweak collaboration (1644 authors); David, A.; Abreu, P.; Andringa, S.; Anjos, N.; Castro, N.; De Angelis, A.Electroweak measurements performed with data taken at the electron-positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3 fb$^{-1}$ collected by the four LEP experiments ALEPH, DELPHI, L3 and OPAL, at centre-of-mass energies ranging from 130 GeV to 209 GeV. Combining the published results of the four LEP experime...
Search for Charged Higgs bosons: Combined Results Using LEP Data
ALEPH, DELPHI, L3, OPAL, LEP collaboration (1216 authors); Abreu, P.; Andringa, S.; Anjos, N.; Castro, Nuno Filipe; De Angelis, A.; Espirito Santo, M.C.The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for pair-produced charged Higgs bosons in the framework of Two Higgs Doublet Models (2HDMs). The data of the four experiments are statistically combined. The results are interpreted within the 2HDM for Type I and Type II benchmark scenarios. No statistically significant excess has been observed when compared to the Standard Model background ...
Nuclear instruments & methods in physics research section a-accelerators spectr...
Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, Ivone Freire da Mota e; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Castillo, J. AlvarezAcesso restrito: Texto completo. p. 92-102; Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2012-02-28T13:55:21Z No. of bitstreams: 1 __pdn.sciencedirect.com_....0-S0168900211001276-main.pdf: 705611 bytes, checksum: be1943c8aeefcedd5fa515742b173dc0 (MD5); Made available in DSpace on 2012-02-28T13:55:21Z (GMT). No. of bitstreams: 1 __pdn.sciencedirect.com_....0-S0168900211001276-main.pdf: 705611 byt...
A Search for Point Sources of EeV Neutrons
Pierre Auger collaboration (509 authors); Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.A thorough search of the sky exposed at the Pierre Auger Cosmic Ray Observatory reveals no statistically significant excess of events in any small solid angle that would be indicative of a flux of neutral particles from a discrete source. The search covers from -90 to +15 degrees in declination using four different energy ranges above 1 EeV (10^18 eV). The method used in this search is more sensitive to neutron...
A search for anisotropy in the arrival directions of ultra high energy cosmic r...
Pierre Auger collaboration (501 authors); Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.Observations of cosmic ray arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a dif...
Search for point-like sources of ultra-high energy neutrinos at the Pierre Auge...
Pierre Auger collaboration (510 authors); Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.The Surface Detector array of the Pierre Auger Observatory can detect neutrinos with energy between 10^17 eV and 10^20 eV from point-like sources across the sky south of +55 deg and north of -65 deg declinations. A search has been performed for highly inclined extensive air showers produced by the interaction of neutrinos of all flavours in the atmosphere (downward-going neutrinos), and by the decay of tau lept...