The Method of Auxiliary Sources as an Efficient Numerical Technique for Large 3D Semi Open Structures

The method of auxiliary sources (MAS) has been demonstrated as suitable for solution of diffraction and inverse problems in complex 2D large objects. Based on MAS numerical study of 3D RCS, EMC/EMI and SAR problems, related to the EM field resonance enhancement inside vehicles and the interaction of the cellular telephone radiation with the user\u27\u27s head are given in other work. The objective of this paper is to present details of MAS application to the wide 3D electrodynamic problems. The area of its efficient application, some features and advantages to achieving efficient solutions, are discussed. The extension of the MAS for semi-open structures with partitions is also presented

Electromagnetic Analysis for Vehicle Antenna Development Using Method of Auxiliary Sources

In paper [l] the electromagnetic analysis of large semi-open structures like vehicles was presented formulated as scattering problem, illuminated by a wide range of incident EM fields. The effect of resonances within the semi-open structure on the RCS, near fields and pattem of reradiated fields had been shown. In this paper the interaction of the entire semi-open structure on the performance of an antenna is considered together with the investigation of near field distributions inside the cavity. The Method of Auxiliary Sources (MAS) [2] is utilized. For a simple geometry the results are compared to measurements

MAS-MoM Hybrid Method with Wire\u27s Image using in Excitation Problems

An important class of problems is the interaction of an antenna with the cavity of a semi-open metallic structure. In a working environment, an antenna may change its performance due to interactions with its surroundings. This is especially true in automotive applications. Therefore, it is important to consider the interaction of an antenna with possible resonating parts, and to solve these complex electrodynamics problems together. The development of methods for modeling and studying electromagnetic compatibility (EMC) problems has practical value. The method of auxiliary sources (MAS) with the method of moments (MoM) is applied to solve the excitation problem where a wire, with voltage source excitation, is connected to an open metallic surface. For verification of the proposed algorithm, an experimental structure was built and measured. Computer modeling results and the experimental results are in good agreement. Some aspects and principles are described, which provide hybridization of MAS and MoM. Image of objects is effectively applied for the solution of the particular problem

KM3NeT broadcast optical data transport system

The optical data transport system of the KM3NeT neutrino telescope at the bottom of the Mediterranean Sea will provide more than 6000 optical modules in the detector arrays with a point-to-point optical connection to the control stations onshore. The ARCA and ORCA detectors of KM3NeT are being installed at a depth of about 3500 m and 2500 m, respectively and their distance to the control stations is about 100 kilometers and 40 kilometers. In particular, the two detectors are optimised for the detection of cosmic neutrinos with energies above about 1 TeV (ARCA) and for the detection of atmospheric neutrinos with energies in the range 1 GeV-1 TeV (ORCA). The expected maximum data rate is 200 Mbps per optical module. The implemented optical data transport system matches the layouts of the networks of electro-optical cables and junction boxes in the deep sea. For efficient use of the fibres in the system the technology of Dense Wavelength Division Multiplexing is applied. The performance of the optical system in terms of measured bit error rates, optical budget are presented. The next steps in the implementation of the system are also discussed

Probing invisible neutrino decay with KM3NeT-ORCA

In the era of precision measurements of the neutrino oscillation parameters, upcoming neutrino experiments will also be sensitive to physics beyond the Standard Model. KM3NeT/ORCA is a neutrino detector optimised for measuring atmospheric neutrinos from a few GeV to around 100 GeV. In this paper, the sensitivity of the KM3NeT/ORCA detector to neutrino decay has been explored. A three-flavour neutrino oscillation scenario, where the third neutrino mass state $\nu_3$ decays into an invisible state, e.g. a sterile neutrino, is considered. We find that KM3NeT/ORCA would be sensitive to invisible neutrino decays with $1/\alpha_3=\tau_3/m_3 < 180$~$\mathrm{ps/eV}$ at $90\%$ confidence level, assuming true normal ordering. Finally, the impact of neutrino decay on the precision of KM3NeT/ORCA measurements for $\theta_{23}$, $\Delta m^2_{31}$ and mass ordering have been studied. No significant effect of neutrino decay on the sensitivity to these measurements has been found.Comment: 27 pages, 14 figures, bibliography updated, typos correcte

First observation of the cosmic ray shadow of the Moon and the Sun with KM3NeT/ORCA

This article reports the first observation of the Moon and the Sun shadows in the sky distribution of cosmic-ray induced muons measured by the KM3NeT/ORCA detector. The analysed data-taking period spans from February 2020 to November 2021, when the detector had 6 Detection Units deployed at the bottom of the Mediterranean Sea, each composed of 18 Digital Optical Modules. The shadows induced by the Moon and the Sun were detected at their nominal position with a statistical significance of 4.2 σ and 6.2 σ , and an angular resolution of σres= 0. 49 ∘ and σres= 0. 66 ∘ , respectively, consistent with the prediction of 0. 53 ∘ from simulations. This early result confirms the effectiveness of the detector calibration, in time, position and orientation and the accuracy of the event direction reconstruction. This also demonstrates the performance and the competitiveness of the detector in terms of pointing accuracy and angular resolution

KM3NeT broadcast optical data transport system

The optical data transport system of the KM3NeT neutrino telescope at the bottom of the Mediterranean Sea will provide more than 6000 optical modules in the detector arrays with a point-to-point optical connection to the control stations onshore. The ARCA and ORCA detectors of KM3NeT are being installed at a depth of about 3500 m and 2500 m, respectively and their distance to the control stations is about 100 kilometers and 40 kilometers. In particular, the two detectors are optimised for the detection of cosmic neutrinos with energies above about 1 TeV (ARCA) and for the detection of atmospheric neutrinos with energies in the range 1 GeV–1 TeV (ORCA). The expected maximum data rate is 200 Mbps per optical module. The implemented optical data transport system matches the layouts of the networks of electro-optical cables and junction boxes in the deep sea. For efficient use of the fibres in the system the technology of Dense Wavelength Division Multiplexing is applied. The performance of the optical system in terms of measured bit error rates, optical budget are presented. The next steps in the implementation of the system are also discussed

First observation of the cosmic ray shadow of the Moon and the Sun with KM3NeT/ORCA

Abstract This article reports the first observation of the Moon and the Sun shadows in the sky distribution of cosmic-ray induced muons measured by the KM3NeT/ORCA detector. The analysed data-taking period spans from February 2020 to November 2021, when the detector had 6 Detection Units deployed at the bottom of the Mediterranean Sea, each composed of 18 Digital Optical Modules. The shadows induced by the Moon and the Sun were detected at their nominal position with a statistical significance of 4.2 $$\sigma$$ σ and 6.2 $$\sigma$$ σ , and an angular resolution of $$\sigma _{res}=0.49^\circ$$ σ res = 0 . 49 ∘ and $$\sigma _{res}=0.66^\circ$$ σ res = 0 . 66 ∘ , respectively, consistent with the prediction of $$0.53^\circ$$ 0 . 53 ∘ from simulations. This early result confirms the effectiveness of the detector calibration, in time, position and orientation and the accuracy of the event direction reconstruction. This also demonstrates the performance and the competitiveness of the detector in terms of pointing accuracy and angular resolution