Abstract: The experimental confirmation of non-vanishing neutrino masses at the sub-eV range poses a challenge for the (otherwise successful) Standard Model (SM). The EW- nu R model, which gives a solution to this problem via a seesaw mechanism with non-sterile right-handed neutrinos at the electroweak scale, contains mirror fermion doublets and singlets with opposite chirality assignments under the same SUW(2) gauge symmetry. It also features a viable dark-matter candidate and proposes a solution to the strong CP problem. The (electroweak scale) mirror quarks (leptons) decay to SM quarks (leptons) plus very light neutral scalars, giving final states with jets or leptons, scalar mesons and missing momentum. In this paper, we review the signatures through which these mirror particles can be probed at colliders such as the Large Hadron Collider. Emphasis is given to long-lived mirror particles, depending on the associated Yukawa couplings, that can give rise to observable displaced leptons and jets, and heavy hadrons.z

Abstract: Context. The detection of the highest energy neutrino observed to date by KM3NeT, with an estimated energy of 220 PeV, opens up new possibilities for the study and identification of the astrophysical sources responsible for a di ffuse flux of such ultra-high-energy neutrinos, among which gamma-ray bursts are longstanding candidates. Aims. Based on the event KM3-230213A, we derived constraints on the baryon loading and density of the surrounding environment in models of blast waves in long-duration gamma-ray bursts. Methods. We computed the di ffuse flux from gamma-ray burst blast waves, either expanding in a constant density interstellar medium or developing in a radially decreasing density of a wind-like environment surrounding the gamma-ray burst progenitor star, by taking into account the expected neutrino spectra and luminosity function. We used a Poisson likelihood method to constrain the blast wave model parameters by calculating the expected number of neutrino events within the 90% confidence level energy range of KM3-230213A and by using the joint exposure of KM3NeT/ARCA, IceCube, and Pierre Auger. Results. We constrain the baryon loading to be f(b) <= 51 at 90% confidence, with the best-fit and 68% confidence interval being f(b) = 26.9(-17.2)(+11.4) for a constant interstellar medium particle density of n(0) = 1 cm(-3). In the wind-like environment case, the baryon loading is fb similar to 1095 at 90% confidence, with the corresponding 68% confidence interval being f(b) is an element of [8, 231], which is proportional to the sixth power of a variable density parameter of A(*) = 0.1.

Abstract: Turbulence is indispensable to redistribute nutrients for all life forms larger than microbial, on land and in the ocean. Yet, the development of deep-sea turbulence was not studied in three dimensions to date. As a disproportionate laboratory, an array of nearly 3,000 high-resolution temperature sensors had been installed for three years on the flat 2,500-m deep bottom of the Mediterranean Sea. The time series from the half-cubic hectometer mooring-array allows for the creation of unique movies of deep-sea water motions. Although temperature differences are typically 0.001 degrees C, variable convection-turbulence is observed as expected from geothermal heating through the flat seafloor. During about 40% of the time, an additional turbulence, 3 times stronger in magnitude, is observed from slantwise advected warmer waters to pass in turbulent clouds. Besides turbulent clouds and seafloor heating, movies also reveal weakly turbulent interfacial-wave breakdown that commonly occurs in the open ocean far away from boundaries.