Calibration of the absolute amplitude scale of the Tunka Radio Extension (ICRC 2015)

R. Hiller; P. A. Bezyazeekov; N. M. Budnev; O. A. Gress; A. Haungs; T. Huege; Y. Kazarina; M. Kleifges; E. N. Konstantinov; E. E. Korosteleva; D. Kostunin; O. Krömer; L. A. Kuzmichev; N. Lubsandorzhiev; R. R. Mirgazov; R. Monkhoev; A. Pakhorukov; L. Pankov; V. V. Prosin; G. I. Rubtsov; F. G. Schröder; R. Wischnewski; A. Zagorodnikov

arXiv · 1508.06210

Calibration of the absolute amplitude scale of the Tunka Radio Extension (ICRC 2015)

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Abstract

The Tunka Radio Extension (Tunka-Rex) is an array of 44 radio antenna stations, distributed over 3 km$^{2}$, constituting a radio detector for air showers with an energy threshold around 10$^{17}$ eV. It is an extension to Tunka-133, an air-Cherenkov detector in Siberia, which is used as an external trigger for Tunka-Rex and provides a reliable reconstruction of energy and shower maximum. Each antenna station consists of two perpendicularly aligned active antennas, called SALLAs. An antenna calibration of the SALLA with a commercial reference source enables us to reconstruct the detected radio signal on an absolute scale. Since the same reference source was used for the calibration of LOPES and, in a calibration campaign in 2014, also for LOFAR, these three experiments now have a consistent calibration and, therefore, absolute scale. This was a key ingredient to resolve a longer standing contradiction between measurements of two calibrated experiments. We will present how the calibration was performed and compare radio measurements of air showers from Tunka-Rex to model calculations with the radio simulation code CoREAS, confirming it within the scale uncertainty of the calibration of 18%.

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R. Hiller, P. A. Bezyazeekov, N. M. Budnev, O. A. Gress, A. Haungs, T. Huege, Y. Kazarina, M. Kleifges, E. N. Konstantinov, E. E. Korosteleva, D. Kostunin, O. Krömer, L. A. Kuzmichev, N. Lubsandorzhiev, R. R. Mirgazov, R. Monkhoev, A. Pakhorukov, L. Pankov, V. V. Prosin, G. I. Rubtsov, F. G. Schröder, R. Wischnewski, A. Zagorodnikov. 2015-08-25. Calibration of the absolute amplitude scale of the Tunka Radio Extension (ICRC 2015). https://arxiv.org/abs/1508.06210

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