A Scintillator and Radio Enhancement of the IceCube Surface Detector Array

An upgrade of the present IceCube surface array (IceTop) with scintillation detectors and possibly radio antennas is foreseen. The enhanced array will calibrate the impact of snow accumulation on the reconstruction of cosmic-ray showers detected by IceTop as well as improve the veto capabilities of the surface array. In addition, such a hybrid surface array of radio antennas, scintillators and Cherenkov tanks will enable a number of complementary science targets for IceCube such as enhanced accuracy to mass composition of cosmic rays, search for PeV photons from the Galactic Center, or more thorough tests of the hadronic interaction models. Two prototype stations with 7 scintillation detectors each have been already deployed at the South Pole in January 2018. These R&D studies provide a window of opportunity to integrate radio antennas with minimal effort.Comment: 6 pages, conference proceedings of UHECR 201

Cosmic Rays from the Knee to the Ankle

Investigations of the energy spectrum as well as the mass composition of cosmic rays in the energy range of PeVto EeV are important for understanding both, the origin of the galactic and the extragalactic cosmic rays. Recently, three modern experimental installations (KASCADE-Grande, IceTop, Tunka-133), dedicated to investigate this primary energy range, have published new results on the all-particle energy spectrum. In this short review these results are presented and the similarities and differences discussed. In addition, the effects of using different hadronic interaction models for interpreting the measured air-shower data will be examined. Finally, a brief discussion on the question if the present results are in agreement or in contradiction with astrophysical models for the transition from galactic to 10 pagesextragalactic origin of cosmic rays completes this paper.Comment: 10 pages, proceedings of TAUP 2013 conferenc

Air Shower Measurements in the Primary Energy Range from PeV to EeV

Recent results of advanced experiments with sophisticated measurements of cosmic rays in the energy range of the so called knee at a few PeV indicate a distinct knee in the energy spectra of light primary cosmic rays and an increasing dominance of heavy ones towards higher energies. This leads to the expectation of knee-like features of the heavy primaries at around 100 PeV. To investigate in detail this energy region several new experiments are or will be devised.Comment: 4 pages; submitted to Proceedings of 2nd Workshop on TeV Astrophysics, Aug 28-31, 2006, Madison, W

Status of JEM-EUSO and its test experiments EUSO-Balloon and TA-EUSO

The JEM-EUSO mission will explore the origin of the extreme energy cosmic rays (EECRs) through the observation of their arrival directions and energies. The super-wide-field telescope looks down from the International Space Station onto the night sky to detect UV photons fluorescence and Cherenkov photons) emitted from air showers generated by EECRs in the Atmosphere. Such a space detector offers the opportunity to observe a huge volume of atmosphere at once and will achieve unprecedented statistical accuracy within a few years of operation. The JEM-EUSO mission will be installed on the Japanese module of the International Space Station. Two test experiments are currently prepared; one to observe the fluorescence background from the edge of the Atmosphere (EUSO-Balloon), and the other to demonstrate, on ground, the capability of all sub-systems of the EUSO instrument (TA-EUSO). In this paper a short review on the scientific objectives and an update of the instrument definition, performances and status of the mission, as well as of the status of the two preceded test experiments will be given

Enhancing the cosmic-ray mass sensitivity of air-shower arrays by combining radio and muon detectors

The muonic and electromagnetic components of air showers are sensitive to the mass of the primary cosmic particle. The sizes of the components can be measured with particle detectors on ground, and the electromagnetic component in addition indirectly via its radio emission in the atmosphere. The electromagnetic particles do not reach the ground for very inclined showers. On the contrary, the atmosphere is transparent for the radio emission and its footprint on ground increases with the zenith angle. Therefore, the radio technique offers a reliable detection over the full range of zenith angles, and in particular for inclined showers. In this work, the mass sensitivity of a combination of the radio emission with the muons is investigated in a case study for the site of the Pierre Auger Observatory using CORSIKA Monte Carlo simulations of showers in the EeV energy range. It is shown, that the radio-muon combination features superior mass separation power in particular for inclined showers, when compared to established mass observables such as a combination of muons and electrons or the shower maximum Xmax. Accurate measurements of the energy-dependent mass composition of ultra-high energy cosmic rays are essential to understand their still unknown origin. Thus, the combination of muon and radio detectors can enhance the scientific performance of future air-shower arrays and offers a promising upgrade option for existing arrays

Characterization of Hamamatsu 64-channel TSV SiPMs

The Hamamatsu UV-light enhanced 64-channel SiPM array of the newest generation (S13361-3050AS-08) has been examined for the purpose of being used for the Silicon Elementary Cell Add-on (SiECA) of the EUSO-SPB balloon experiment. Characterization measurements have been performed with the newly installed Single Photon Calibration Stand at KIT (SPOCK). The results of the characterization measurements including the breakdown voltage, the gain, the PDE, the dark-count rate and the crosstalk probability of all 64 SiPM channels are presented. Additional measurements of the SiPM sensitivity to photons with wavelengths lower than 400nm show an improved PDE for small wavelengths compared to the SiPM array S12642-0808PA-50, which was also investigated for comparison. The response dynamics have been investigated for low numbers of incoming photons. Temperature dependent measurements of the gain, the PDE, the dark-count rate and the crosstalk probability have been performed for one channel of the SiPM array.Comment: Accepted for publication in Nuclear Instruments and Methods