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Over the last 25 years, radiowave detection of neutrino-generated signals, using cold polar ice as the neutrino target, has emerged as perhaps the most promising technique for detection of extragalactic ultra-high energy neutrinos (corresponding to neutrino energies in excess of 0.01 Joules, or 1017 electron volts). During the summer of 2021 and in tandem with the initial deployment of the Radio Neutrino Observatory in Greenland (RNO-G), we conducted radioglaciological measurements at Summit Station, Greenland to refine our understanding of the ice target. We report the result of one such measurement, the radio-frequency electric field attenuation length $L_\alpha$. We find an approximately linear dependence of $L_\alpha$ on frequency with the best fit of the average field attenuation for the upper 1500 m of ice: $\langle L_\alpha \rangle = ( ( 1154 \pm 121) - ( 0.81 \pm 0.14) \, ( \nu /{\rm MHz}) ) \,{\rm m}$ for frequencies ν ∈ [145 − 350] MHz.

Abstract Since summer 2021, the Radio Neutrino Observatory in Greenland (RNO-G) is searching for astrophysical neutrinos at energies $${>10}$$ > 10 PeV by detecting the radio emission from particle showers in the ice around Summit Station, Greenland. We present an extensive simulation study that shows how RNO-G will be able to measure the energy of such particle cascades, which will in turn be used to estimate the energy of the incoming neutrino that caused them. The location of the neutrino interaction is determined using the differences in arrival times between channels and the electric field of the radio signal is reconstructed using a novel approach based on Information Field Theory. Based on these properties, the shower energy can be estimated. We show that this method can achieve an uncertainty of 13% on the logarithm of the shower energy after modest quality cuts and estimate how this can constrain the energy of the neutrino. The method presented in this paper is applicable to all similar radio neutrino detectors, such as the proposed radio array of IceCube-Gen2.

The Askaryan Radio Array (ARA) experiment at the South Pole is designed to detect high-energy neutrinos which, via in-ice interactions, produce coherent radiation at frequencies up to 1000 MHz. Characterization of ice birefringence, and its effect upon wave polarization, is proposed to enable range estimation to a neutrino interaction and hence aid in neutrino energy reconstruction. Using radio transmitter calibration sources, the ARA collaboration recently measured polarization-dependent time delay variations and reported significant time delays for trajectories perpendicular to ice flow, but not parallel. To explain these observations, and assess the capability for range estimation, we use fabric data from the SPICE ice core to model ice birefringence and construct a bounding radio propagation model that predicts polarization time delays. We compare the model with new data from December 2018 and demonstrate that the measurements are consistent with the prevailing horizontal crystallographic axis aligned near-perpendicular to ice flow. The study supports the notion that range estimation can be performed for near flow-perpendicular trajectories, although tighter constraints on fabric orientation are desirable for improving the accuracy of estimates.

Abstract NuRadioMC is a Monte Carlo framework designed to simulate ultra-high energy neutrino detectors that rely on the radio detection method. This method exploits the radio emission generated in the electromagnetic component of a particle shower following a neutrino interaction. NuRadioMC simulates everything from the neutrino interaction in a medium, the subsequent Askaryan radio emission, the propagation of the radio signal to the detector and finally the detector response. NuRadioMC is designed as a modern, modular Python-based framework, combining flexibility in detector design with user-friendliness. It includes a state-of-the-art event generator, an improved modelling of the radio emission, a revisited approach to signal propagation and increased flexibility and precision in the detector simulation. This paper focuses on the implemented physics processes and their implications for detector design. A variety of models and parameterizations for the radio emission of neutrino-induced showers are compared and reviewed. Comprehensive examples are used to discuss the capabilities of the code and different aspects of instrumental design decisions.

Background. Ketogenic diet has been used as supportive therapy in a range of conditions including epilepsy, diabetes mellitus, and cancer. Objective. This study aimed to investigate the effects of long-term consumption of ketogenic diet on blood gas, hematological profiles, organ functions, and superoxide dismutase level in a rat model. Materials and Methods. Fifteen male Wistar rats were divided into control (n = 8) and ketogenic (n = 7) groups. Controls received standard diet contained 52.20% of carbohydrates, 7.00% fat, and 15.25% protein; meanwhile, the ketogenic group received a high-fat-low-carbohydrate diet which contained 5.66% of carbohydrate, 86.19% fat, and 8.15% protein. All rats were caged individually and received 30g of either standard or high-fat-low-carbohydrate pellets. The experiment was carried out for 60 days before the blood samples were taken and analyzed to obtain blood gas, cell counts, organ biomarkers, and plasma antioxidant superoxide dismutase (SOD) levels. Results. The rats subjected to ketogenic diet experienced a marked decrease in body weight, blood sugar, and increased blood ketones (p

Penelitian bertujuan untuk mengevaluasi pengaruh lama penyimpanan terhadap kualitas interior telur ayam Kedu jengger merah. Materi yang digunakan adalah 113 butir telur ayam kedu jengger merah. Rancangan yang digunakan adalah Rancangan Acak Lengkap (RAL) dengan 5 perlakuan dan 5 ulangan. Perlakuan yang digunakan yaitu penyimpanan telur 1 hari (T0), penyimpanan telur 3 hari (T1), penyimpanan telur 5 hari (T2), penyimpanan telur 7 hari (T3) dan penyimpanan telur 9 hari (T4). Parameter yang diamati meliputi bobot putih telur, bobot kuning telur dan haugh unit. Hasil penelitian menunjukkan bahwa lama penyimpanan berpengaruh nyata (p