1,270 research outputs found
Comparison between methods for the determination of the primary cosmic ray mass composition from the longitudinal profile of atmospheric cascades
The determination of the primary cosmic ray mass composition from the
longitudinal development of atmospheric cascades is still a debated issue. In
this work we discuss several data analysis methods and show that if the entire
information contained in the longitudinal profile is exploited, reliable
results may be obtained. Among the proposed methods FCC ('Fit of the Cascade
Curve'), MTA ('Multiparametric Topological Analysis') and NNA ('Neural Net
Analysis') with conjugate gradient optimization algorithm give the best
accuracy.Comment: 22 pages, 11 figures, accepted by Astroparticle Physics, minor
misprints and an extra figure remove
Precise determination of muon and electromagnetic shower contents from shower universality property
We consider two new aspects of Extensive Air Shower development universality
allowing to make accurate estimation of muon and electromagnetic (EM) shower
contents in two independent ways. In the first case, to get muon (or EM) signal
in water Cherenkov tanks or in scintillator detectors it is enough to know the
vertical depth of shower maximum and the total signal in the ground detector.
In the second case, the EM signal can be calculated from the primary particle
energy and the zenith angle. In both cases the parametrizations of muon and EM
signals are almost independent on primary particle nature, energy and zenith
angle. Implications of the considered properties for mass composition and
hadronic interaction studies are briefly discussed. The present study is
performed on 28000 of proton, oxygen and iron showers, generated with CORSIKA
6.735 for spectrum in the energy range log(E/eV)=18.5-20.0 and
uniformly distributed in cos^2(theta) in zenith angle interval theta=0-65
degrees for QGSJET II/Fluka interaction models.Comment: Submitted to Phys. Rev.
Carbon Nanotubes-Based Radiation Detectors
Communications engineering / telecommunication
A new multiparametric topological method for determining the primary cosmic ray mass composition in the knee energy region
The determination of the primary cosmic ray mass composition from the
characteristics of extensive air showers (EAS), obtained at an observation
level in the lower half of the atmosphere, is still an open problem. In this
work we propose a new method of the Multiparametric Topological Analysis and
show its applicability for the determination of the mass composition of the
primary cosmic rays at the PeV energy region.Comment: 8 pages, 4 figures, talk given at Vulcano 2004 Workshop 'Frontier
Objects in Physics and Astrophysics', Vulcano, Italy, 24-29.05.04, to be
published in the Proceedings of the Worksho
Chapter Carbon Nanotubes-Based Radiation Detectors
Communications engineering / telecommunication
Simulation of up- and down-going neutrino induced showers at the site of the Pierre Auger Observatory
We present a study about the possibility to detect neutrino induced extensive
air showers at the Pierre Auger Observatory. The Monte Carlo simulations
performed take into account the details of the neutrino propagation inside the
Earth, the air as well as the surrounding mountains which are modelled by a
digital elevation map. Details on the sensitivity with respect to the incoming
direction as well as the aperture and the total observable event rates are
calculated on the basis of various assumptions of the incoming neutrino flux.Comment: Based on a talk presented at European Cosmic Ray Symposium, Lisbon,
September 200
Replacing Project Manager: Reasons of Replacement Interpreted through the Activity Theory
In this study the reasons for replacing a project manager (RPM) during an ongoing IT project are classified. We give an interpretation on a project through the lens of Activity Theory (AT) and examine the tensions leading to RPM through the principle of contradiction in AT. We interviewed four experienced supervisors of three large project-based companies in the IT field, reviewed a previous study on RPM, and used the concept of contradiction to interpret the types of RPM. We found six types of reasons for RPM (e.g., the project manager has not achieved the defined objectives) and underlying the contradictions we identified interests of the client, the company and project manager which all affect to the emergence of RPM. Our results entail implications for research and practice on RPM
Ultrahigh Energy Cosmic Rays Detection
The paper describes methods used for the detection of cosmic rays with
energies above 10^18 eV (UHECR, UltraHigh Energy Cosmic Rays). It had been
anticipated there would be a cutoff in the energy spectrum of primary cosmic
rays around 3 10^19 eV induced by their interaction with the 2.7 K primordial
photons. This has become known as the GZK cutoff. However, several showers have
been detected with estimated primary energy exceeding this limit.Comment: 4 pages, 4 figures. To appear in the proceedings of 17th Conference
on High Energy Physics (IFAE 2005) (In Italian), Catania, Italy, 30 Mar - 2
Apr 200
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