Cosmic Ray Mass Measurements with LOFAR

• Main Authors: Buitink Stijn, Bonardi Antonio, Corstanje Arthur, Enriquez J. Emilio, Falcke Heino, Hörandel Jörg R., Mitra Pragati, Mulrey Katie, Nelles Anna, Rachen Jörg Paul, Rossetto Laura, Schellart Pim, Scholten Olaf, Thoudam Satyendra, Trinh Gia, ter Veen Sander, Winchen Tobias
• Format: Article
• Language: English
• Published: EDP Sciences 2017-01-01
• Series: EPJ Web of Conferences
• Online Access: https://doi.org/10.1051/epjconf/201713501009

In the dense core of LOFAR individual air showers are detected by hundreds of dipole antennas simultaneously. We reconstruct Xmax by using a hybrid technique that combines a two-dimensional fit of the radio profile to CoREAS simulations and a one-dimensional fit of the particle density distribution. For high-quality detections, the statistical uncertainty on Xmax is smaller than 20 g/cm2. We present results of cosmic-ray mass analysis in the energy regime of 1017 - 1017.5 eV. This range is of particular interest as it may harbor the transition from a Galactic to an extragalactic origin of cosmic rays.