Search

A new mobile detector was developed in IFIN-HH, Romania, for measuring muon flux at surface and in underground. The measurements have been performed in the salt mines of Slanic Prahova, Romania. The muon flux was determined for 2 different galleries of the Slanic mine at different depths. In order to test the stability of the method, also measurements of the muon flux at surface at different altitudes were performed. Based on the results, the depth of the 2 galleries was established at 610 and 790 m.w.e. respectively. [ABSTRACT FROM AUTHOR]

A fesibility study to explore the capability of the WILLI detector to observe the solar events/activity by recording the muon intensity at ground level is presented. The WILLI detector, set up in National Institute of Physics and Nuclear Engineering, Bucharest, is a 1 m2 incident area sampling calorimeter. It can measure simultaneously muon events with the muon energy >=0.4 GeV and, if the muons are stopped in the detector, and muon energy between 0.4μ<0.6 GeV, if the muons pass the minimum of 2 plates of the detector stack. Taking into account muon events with energy >=0.4 GeV, a modulation of the muon intensity as a diurnal variation is observed. Muon events for a smaller energy range (0.4-0.6 GeV) seem to exhibit an aperiodic variation of the muon intensity, which could be correlated with magnetic activity indicated by the planetary Kp index. [ABSTRACT FROM AUTHOR]

The parareal algorithm is a numerical method to integrate evolution problems on parallel computers. While this algorithm is effective for diffusive problems, its convergence properties are much less favorable for hyperbolic problems. We analyze in this paper a recently proposed variant of the parareal algorithm for hyperbolic problems for the case of systems of second order ordinary differential equations. [ABSTRACT FROM AUTHOR]

The WILLI detector, installed in the National Institute of Physics and Nuclear Engineering — Horia Hulubei Bucharest has been devised for studies of atmospheric muons, in particular of the muon charge ratio. We report on the results of studies for various muon energies (pμ < 1 GeV/c). The results are compared with Monte-Carlo simulations performed with the CORSIKA and GEANT codes. We are exploring the potential of a small detector array to be set up nearby the actual WILLI detector for triggering the muon charge ratio measurements by Extended Air Shower (EAS) events. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]