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Astrophysical neutrinos are excellent probes of astroparticle physics and high-energy physics. With energies far beyond solar, supernovae, atmospheric, and accelerator neutrinos, high-energy and ultra-high-energy neutrinos probe fundamental physics from the TeV scale to the EeV scale and beyond. They are sensitive to physics both within and beyond the Standard Model through their production mechanisms and in their propagation over cosmological distances. They carry unique information about their extreme non-thermal sources by giving insight into regions that are opaque to electromagnetic radiation. This white paper describes the opportunities astrophysical neutrino observations offer for astrophysics and high-energy physics, today and in coming years.

Terrestrial gamma‐ray flashes (TGFs) are bright bursts of gamma rays produced by thunderstorms, typically observed by spacecraft in the low‐Earth orbit. Unfortunately, it has been difficult to disentangle the source altitude and the width and direction of the gamma‐ray beam using single point spacecraft measurements, which has hampered attempts to constrain TGF models. Polarimetry of astrophysical sources has been of interest for many decades, which raises the question: Do TGFs and X‐rays from lightning have observable polarization, and if so, what would this polarization tell us about their source? REAM Monte Carlo code has been modified to record the linear polarization of X‐rays and gamma rays as a function of source altitude and beam geometry. It is found that polarization degree of a 20‐km narrow beam of TGF is substantially different from a 15‐km‐wide beam, which could be used to constrain the source geometry of TGFs. However, due to the low fluence of these events in space, detecting this level of polarization would be challenging. It is also found that low‐altitude TGFs (source at 3.5 km) produce polarizations up to about 8%; however, detectors need to be very close to the source region. Furthermore, very low altitude ground‐level TGFs and X‐rays showed a maximum polarization of 13% on the ground, of which the TGF's fluence was large enough for polarimetry. In addition, polarization reached its maximum further away from the zaxis as the TGF's beam broadened. The dominant mechanism of the polarization was found to be Compton scattering. REAM Monte Carlo simulation was used to study the polarization of gamma rays from TGFs and X‐rays from lightningPolarimetry of gamma rays from TGFs does not seem to be practical in space, since too few counts are typically detected by spacecraftsVery low‐altitude ground‐level TGFs produced about 13% polarization on the ground with enough counts to make polarimetry possible

The Runaway Electrons Avalanche Model Monte Carlo simulation is used to study the propagation of runaway electrons and gamma‐ray flashes originating from the atmosphere of Venus, and the possibility of detecting these high‐energy gamma rays at low‐Venus orbit is also investigated. Relativistic Runaway Electron Avalanche (RREA) lengths and energy spectra at the Venus middle cloud levels have similar values to those of Earth at sea level, with a similar RREA threshold electric field (~286 kV/m). If electrified clouds in Venus make similar numbers of gamma rays as are made by thunderstorms on Earth during Terrestrial Gamma‐ray Flashes (TGFs), then the calculated gamma‐ray fluences at low‐Venus orbit (~550 km) have an approximate range of 10−3photons/cm2to 4 photons/cm2for the source altitude between 58 km and 70 km. These gamma‐ray fluences are similar to those measured by spacecraft in low‐Earth orbit from TGFs. Therefore, if TGF‐like events initiate in the middle and upper clouds of Venus, they would be detectable by spacecrafts at low‐Venus orbit. Monte Carlo simulations were used to study the generation and propagation of runaway electrons and gamma‐ray flashes at Venus cloudsThe runaway electron's avalanche length and energy spectra had similar values at the Earth's surface and Venus cloudsIf TGF‐like events happen in the middle and upper clouds of Venus, then such events should be detectable at low‐Venus orbit

The purpose of this study is to evaluate the importance of QM CSFs in Iranian SME's hotels firms. Primary criteria to evaluate QM CSFs are achieved by the literature survey. Through the FDM by industries and academia experts the importance CSFs were categorized in three main factors and 16 sub-factors. Two fuzzy MCDM methods are applied; fuzzy AHPand TOPSIS. The finding of this study indicated that human factors had the first rank from three perspectives and leadership as a sub-factor was the first rank from 16 sub-factors.