LOPES — Recent Results and Open Questions on the Radio Detection of Air Showers

24th European Cosmic Ray Symposium

Schröder, F.G.^1 ; Apel, W.D.^1 ; Arteaga-Velázquez, J.C.^2 ; Bähren, L.^3 ; Bekk, K.^1 ; Bertaina, M.^4 ; Biermann, P.L.^1,5 ; Blümer, J.^1,6 ; Bozdog, H.^1 ; Brancus, I.M.^7 ; Cantoni, E.^4,8 ; Chiavassa, A.^4 ; Daumiller, K.^1 ; De Souza, V.^9 ; Di Pierro, F.^4 ; Doll, P.^1 ; Engel, R.^1 ; Falcke, H.^3,5,10 ; Fuchs, B.^6 ; Gemmeke, H.^11 ; Grupen, C.^12 ; Haungs, A.^1 ; Heck, D.^1 ; Hörandel, J.R.^10 ; Horneffer, A.^5 ; Huber, D.^6 ; Huege, T.^1 ; Isar, P.G.^13 ; Kampert, K.-H.^14 ; Kang, D.^6 ; Krömer, O.^11 ; Kuijpers, J.^10 ; Link, K.^6 ; Luczak, P.^15 ; Ludwig, M.^6 ; Mathes, H.J.^1 ; Melissas, M.^6 ; Morello, C.^8 ; Oehlschläger, J.^1 ; Palmieri, N.^6 ; Pierog, T.^1 ; Rautenberg, J.^14 ; Rebel, H.^1 ; Roth, M.^1 ; Rühle, C.^11 ; Saftoiu, A.^7 ; Schieler, H.^1 ; Schmidt, A.^11 ; Schoo, S.^1 ; Sima, O.^16 ; Toma, G.^7 ; Trinchero, G.C.^8 ; Weindl, A.^1 ; Wochele, J.^1 ; Zabierowski, J.^15 ; Zensus, J.A.^5

Institut für Kernphysik, Karlsruher Institut für Technologie (KIT), Germany^1

Instituto de Física y Matemáticas, Universidad Michoacana, Morelia, Mexico^2

ASTRON, Dwingeloo, Netherlands^3

Dipartimento di Fisica, Università Degli Studi di Torino, Torino, Italy^4

Max-Planck-Institut für Radioastronomie, Bonn, Germany^5

Institut für Experimentelle Kernphysik, Karlsruher Institut für Technologie (KIT), Germany^6

National Institute of Physics and Nuclear Engineering, Bucharest-Magurele, Romania^7

Osservatorio Astrofisico di Torino, INAF Torino, Italy^8

Universidade São Paulo, Instituto de Física de São Carlos, São Carlos, Brazil

(10) Department of Astrophysics, Radboud University Nijmegen, Netherlands

(11) Institut für Prozessdatenverarbeitung und Elektronik, KIT, Germany

(12) Faculty of Natural Sciences and Engineering, Universität Siegen, Germany

(13) Institute for Space Sciences, Bucharest-Magurele, Romania

(14) Fachbereich C, Physik, Universität Wuppertal, Germany

(15) Department of Astrophysics, National Centre for Nuclear Research, Lód, Poland

(16) Department of Physics, University of Bucharest, Bucharest, Romania^9

关键词: Air shower experiments;    Cosmic ray air showers;    Cross correlations;    Digital antennas;    Interferometric techniques;    Lateral distributions;    Measurement uncertainty;    Potential impacts;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/632/1/012102/pdf
DOI  :  10.1088/1742-6596/632/1/012102

来源: IOP

【 摘 要 】

LOPES was a digital antenna array operating for approximately 10 years until spring 2013 at the Karlsruhe Institute of Technology (KIT). Triggered by the co-located KASCADE-Grande air-shower experiment, it measured the radio signal of around 1000 cosmic-ray air showers with energies E 1017eV in an effective band of 43 - 74 MHz. Using the interferometric technique of cross-correlation beamforming, LOPES could reconstruct the shower direction with an accuracy max, with a precision 2. In particular the reconstruction of the shower maximum suffers from significant measurement uncertainties due to the radio-loud environment of the site. This article summarizes our latest results on the reconstruction of the shower maximum, using two independent methods: the steepness of the hyperbolic radio wavefront and the slope of the lateral distribution of the radio amplitude. Moreover, we show vectorial measurements of the electric field with the tripole antennas of the latest LOPES setup. Finally, we discuss open questions as well as the potential impact of the lessons learned at LOPES for future antenna arrays.