Search results for "observatory"
showing 10 items of 329 documents
Search for point-like sources of ultra-high energy neutrinos at the pierre auger observatory and improved limit on the diffuse flux of tau neutrinos
2012
The surface detector array of the Pierre Auger Observatory can detect neutrinos with energy Eν between 1017 eV and 1020 eV from point-like sources across the sky south of +55º and north of −65º declinations. A search has been performed for highly inclined extensive air showers produced by the interaction of neutrinos of all flavors in the atmosphere (downward-going neutrinos), and by the decay of tau leptons originating from tau neutrino interactions in Earth’s crust (Earth-skimming neutrinos). No candidate neutrinos have been found in data up to 2010 May 31. This corresponds to an equivalent exposure of ∼3.5 years of a full surface detector array for the Earth-skimming channel and ∼2 years…
Search for ultrahigh energy neutrinos in highly inclined events at the Pierre Auger Observatory
2011
Erratum: Phys. Rev. D 85, 029902(E) (2012) [http://dx.doi.org/10.1103/PhysRevD.85.029902]
The mass-hierarchy and CP-violation discovery reach of the LBNO long-baseline neutrino experiment.
2014
The next generation neutrino observatory proposed by the LBNO collaboration will address fundamental questions in particle and astroparticle physics. The experiment consists of a far detector, in its first stage a 20 kt LAr double phase TPC and a magnetised iron calorimeter, situated at 2300 km from CERN and a near detector based on a high-pressure argon gas TPC. The long baseline provides a unique opportunity to study neutrino flavour oscillations over their 1st and 2nd oscillation maxima exploring the $L/E$ behaviour, and distinguishing effects arising from $\delta_{CP}$ and matter. In this paper we have reevaluated the physics potential of this setup for determining the mass hierarchy (M…
Removal of streaking artefact in the images of the Pierre Auger Observatory infra-red cameras
2011
In this paper the problem of removing concentric semi-circular stripe artefacts induced by the operating hardware of the infra red cameras of the Pierre Auger Observatory, is tackled. The method builds on top of a recent algorithm for the removal of artefacts, which presents a robust filter, obtained as a combination of Wavelet and Fourier analysis, capable of eliminating horizontal and vertical stripes in images, while trying to preserve structural features and quantitative values of the image. The method requires several parameters which have been tuned by an exhaustive test on a large set of images. The results show that the method is capable to satisfactorily remove the stripe artefacts.
Limits on the diffuse flux of ultra-high energy neutrinos using the Pierre Auger Observatory
2012
Abstract The surface detector array of the Pierre Auger Observatory is sensitive to ultra-high energy neutrinos in the cosmic radiation. These particles can interact close to ground, both through charged and neutral currents in the atmosphere (down-going) and, for tau neutrinos, through the Earth-skimming mechanism (up-going) where a tau lepton is produced in the Earth's crust that can emerge and decay in the atmosphere. Both types of neutrino-induced events produce an inclined shower that can be identified by the presence of a broad time structure of signals in the water-Cherenkov detectors. Using data collected from the surface detector array of the Pierre Auger Observatory, we present th…
A Study for Cloud Parameter Retrieval from the IR Cloud Cameras of the AUGER Observatory
2009
The Pierre Auger Observatory operative in Argentina, studies the ultra-high energy cosmic rays with energies above 1018eV. The atmosphere is also monitored by a collection of different instruments. In this paper we present a study on the retrieval of the cloud coverage from the atmospheric monitoring data collected by the four IR cloud cameras placed in the sites of the Observatory. We discuss two different algorithms that supply pixel by pixel cloudiness information in the form of binary masks. The final objective of the study is collecting different algorithms to obtain a reliable set that allow to overcome most of the more frequent ambiguities due to particular cloud configurations and a…
Measurement of the Proton-Air Cross Section ats=57 TeVwith the Pierre Auger Observatory
2012
We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505 +/- 22(stat)(-36)(+28)(syst)] mb is found.
NEW ASTROMETRIC REDUCTION OF THE SUPERCOSMOS PLATE ARCHIVE: FIRST RESULTS
2019
The arrivals of the new more accuracy reference catalogues and also development of new meth- ods and approaches for reduction astrometric data give the new life for photographic plates archives. Gaia DR2 is not only a giant step in the astrometric accuracy allowing to measure new objects also provides plates archives ob- served in the past with modern accuracy. In this work we present the first results of astrometric reduction in the sys- tem of Gaia DR2 for some photographic plates that were obtained by UK Schmidt telescope (UKST) and digitized by the SuperCOSMOS scanning machine. The UKST is a classical Schmidt with the following parameters: mirror diameter 1.83m; focal length 3.07m; phot…
ON THE “SOLAR SYSTEM SMALL BODIES” ASTROPLATE PROJECT OF THE UKRAINIAN VIRTUAL OBSERVATORY
2019
The UkrVO Joint Digital Archive of astro- plates and the newest digitized data processing services al- lowed us to form a new approach for the creation of catalogs of astrometric and photometric characteristics of the Solar System bodies. Given this, the main goal of this approach was not only to complete the processing with the best possi- ble accuracy of high-quality and unprocessed earlier photo- graphic observations of the Solar System bodies but also to find new original data from these observations. As a result, more than 6,500 new astrometric positions and stellar magnitudes of asteroids, and 3,036 positions of outer planets (Pluto, Uranus, Neptune, Saturn, Jupiter) and their satelli…
Flux and color variations of the quadruply imaged quasar HE 0435-1223
2011
aims: We present VRi photometric observations of the quadruply imaged quasar HE 0435-1223, carried out with the Danish 1.54m telescope at the La Silla Observatory. Our aim was to monitor and study the magnitudes and colors of each lensed component as a function of time. methods: We monitored the object during two seasons (2008 and 2009) in the VRi spectral bands, and reduced the data with two independent techniques: difference imaging and PSF (Point Spread Function) fitting.results: Between these two seasons, our results show an evident decrease in flux by ~0.2-0.4 magnitudes of the four lensed components in the three filters. We also found a significant increase (~0.05-0.015) in their V-R …