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Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrated a correlation between the arrival directions of cosmic rays with energy above 6 x 10(19) electron volts and the positions of active galactic nuclei (AGN) lying within approximately 75 megaparsecs. We rejected the hypothesis of an isotropic distribution of these(More)
Cosmic rays with energies above 10 18 eV are currently of considerable interest in astrophysics and are to be further studied in a number of projects which are either currently under construction or the subject of well-developed proposals. This paper aims to discuss some of the physics of such particles in terms of current knowledge and information from(More)
The average mass composition of cosmic rays with primary energies between 10 17 and 10 18 eV has been studied using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum and the muon density as a function of energy. The results show(More)
– 2 – Observations of the PSR B1259−63/SS2883 binary system using the CANGAROO-II Cherenkov telescope are reported. This nearby binary consists of a 48 msec radio pulsar in a highly eccentric orbit around a Be star, and offers a unique laboratory to investigate the interactions between the outflows of the pul-sar and Be star at various distances. It has(More)
Two patients were treated for a previously unreported disorder believed to be related to Marcus Gunn jaw-winking. The first, a 9-month-old infant with left congenital blepharoptosis without jaw-winking and with normal ocular motility had an up and down movement of the left globe synchronous with nursing movements of the jaw. The second was a 5-year-old girl(More)
Rapid radio intra-day variability (IDV) has been discovered in the southern quasar PKS 1257−326. Flux density changes of up to 40% in as little as 45 minutes have been observed in this source, making it, along with PKS 0405−385 and J1819+3845, one of the three most rapid IDV sources known. We have monitored the IDV in this source with the Australia(More)
The High Resolution Fly's Eye (HiRes) experiment is an air fluorescence detector which, operating in stereo mode, has a typical angular resolution of 0.6 • and is sensitive to cosmic rays with energies above 10 18 eV. HiRes is thus an excellent instrument for the study of the arrival directions of ultrahigh energy cosmic rays. We present the results of a(More)
The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from nu(tau) charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and(More)
We observed the unidentified TeV gamma-ray source HESS J1804−216 with the CANGAROO-III atmospheric Cerenkov telescopes from May to July in 2006. We detected very high energy gamma rays above 600 GeV at the 10σ level in an effective exposure of 76 hr. We obtained a differential flux of (5.0 ± 1.5 stat ± 1.6 sys) × 10 −12 (E/1 TeV) −α cm −2 s −1 TeV −1 with a(More)
Measurements of cosmic ray directional properties at about 10 15 eV in both northern and southern hemispheres confirm that those particles have a unidirectional anisotropy and are flowing along the direction of our spiral arm from the inner Galactic regions. On the basis of diffusive cosmic ray flow along the Galactic arms, the power required for the Galaxy(More)