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

Einsatz von Luzernetrockenblatt in der ökologischen Broilermast

In einem Fütterungsversuch sollte untersucht werden, wie sich eine sukzessive Steigerung der Luzerneblattanteile in Alleinfuttermischungen auf die Leistung von Masthühnern auswirkt und ob die Trocknungstemperatur des verwendeten Luzerneblatt­materials einen Einfluss auf den Futterverbrauch und die Gewichtsentwicklung der Tiere hat (Niedertemperaturtrocknung (LBnT) vs. Heißlufttrocknung (LB)). Es wurden 600 männliche Hubbard JA-757 Broiler auf 5 Fütterungsvarianten mit je 5 Wiederholungen verteilt (Kontrolle (K), LB 2, LB 3, LB 4, LBnT 5). Die Mast war in 3 Phasen unterteilt, die Anteile an Luzerneblattmehl wurden von Phase zu Phase um je 5% gesteigert (K: 0%-0%-0%; LB 2: 0%-5%-10%); LB 3: 5%-10%-15%; LB 4: 10%-15%-20%; LBnT 5: 10%-15%-20%). Die Tiere der Gruppe K erreichten das höchste Mastendgewicht. Die geringsten Gewichte zeigten die Gruppen LB 3, LB 4 und LBnT 5. Der Einsatz von Luzerneblattmehl, besonders der frühe Einsatz (5% ab Phase 1) und die Einmischung höherer Anteile (15-20%), führten zu signifikanten Leistungsdepressionen bei den wachsenden Broilern, welche vermutlich durch antinutritive Substanzen der Luzernepflanze (Saponine) ausgelöst wurden

TatS: a novel in vitro tattooed human skin model for improved pigment toxicology research

Reports of tattoo-associated risks boosted the interest in tattoo pigment toxicity over the last decades. Nonetheless, the influence of tattoo pigments on skin homeostasis remains largely unknown. In vitro systems are not available to investigate the interactions between pigments and skin. Here, we established TatS, a reconstructed human full-thickness skin model with tattoo pigments incorporated into the dermis. We mixed the most frequently used tattoo pigments carbon black (0.02 mg/ml) and titanium dioxide (TiO2, 0.4 mg/ml) as well as the organic diazo compound Pigment Orange 13 (0.2 mg/ml) into the dermis. Tissue viability, morphology as well as cytokine release were used to characterize TatS. Effects of tattoo pigments were compared to monolayer cultures of human fibroblasts. The tissue architecture of TatS was comparable to native human skin. The epidermal layer was fully differentiated and the keratinocytes expressed occludin, filaggrin and e-cadherin. Staining of collagen IV confirmed the formation of the basement membrane. Tenascin C was expressed in the dermal layer of fibroblasts. Although transmission electron microscopy revealed the uptake of the tattoo pigments into fibroblasts, neither viability nor cytokine secretion was altered in TatS. In contrast, TiO2 significantly decreased cell viability and increased interleukin-8 release in fibroblast monolayers. In conclusion, TatS emulates healed tattooed human skin and underlines the advantages of 3D systems over traditional 2D cell culture in tattoo pigment research. TatS is the first skin model that enables to test the effects of pigments in the dermis upon tattooing

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

Galactic Core-Collapse Supernovae at IceCube: “Fire Drill” Data Challenges and follow-up

The next Galactic core-collapse supernova (CCSN) presents a once-in-a-lifetime opportunity to make astrophysical measurements using neutrinos, gravitational waves, and electromagnetic radiation. CCSNe local to the Milky Way are extremely rare, so it is paramount that detectors are prepared to observe the signal when it arrives. The IceCube Neutrino Observatory, a gigaton water Cherenkov detector below the South Pole, is sensitive to the burst of neutrinos released by a Galactic CCSN at a level >10σ. This burst of neutrinos precedes optical emission by hours to days, enabling neutrinos to serve as an early warning for follow-up observation. IceCube\u27s detection capabilities make it a cornerstone of the global network of neutrino detectors monitoring for Galactic CCSNe, the SuperNova Early Warning System (SNEWS 2.0). In this contribution, we describe IceCube\u27s sensitivity to Galactic CCSNe and strategies for operational readiness, including "fire drill" data challenges. We also discuss coordination with SNEWS 2.0