On 6 June 2020, Pluto's stellar occultation was successfully observed at a ground-based observatory in Iran, and Pluto's atmospheric parameters were investigated. We used an atmospheric model of Pluto, assuming a spherical and transparent pure N 2 atmosphere. Using ray-tracing code, the stellar occultation light curve was satisfactorily fit to this model. We found that Pluto's atmospheric pressure at the reference radius of 1215 km was 6.72 ± 0.48 µbar in June 2020. Our estimated pressure shows a continuation of the pressure increase trend observed since 1988 and does not confirm the rapid pressure decrease tentatively reported in 2019. The pressure evolution is consistent with a seasonal transport model. We conclude that the N 2 sublimation process from Sputnik Planitia is continuing. This study's result is shown on the diagram of the annual evolution of atmospheric pressure.

We study the impact of the coupling of neutrinos with a new light neutral gauge boson, Z′, with a mass of less than 500 MeV in FASERν experiment. Scenarios in which a light gauge boson is coupled to neutrinos are motivated within numerous contexts which are designed to explain various anomalies in particle physics and cosmology. This interaction leads to a new decay mode for charged mesons to a light lepton plus neutrino and Z′, (M + → l + νZ′), followed by the subsequent decay of Z′ into the pair of neutrino and anti-neutrino, (). FASERν, the Forward Search Experiment at the Large Hadron Collider, has the potential to detect collider neutrinos for the first time. In particular, the FASERν emulsion detector will provide the opportunity to detect τ-neutrinos and to measure their energies. Using this ability of FASERν emulsion detector, we investigate the potential of FASERν experiment and the proposed upgraded version of this experiment, FASER2ν, to constrain the coupling of a neutrino with the light gauge boson.

Among different models for determining the habitable zone (HZ) around a star, a Latitudinal Energy Balance Model (LEBM) is very beneficial due to its parametricity which keeps a good balance between complexity and simulation time. This flexibility makes the LEBM an excellent tool to assess the impact of some key physical parameters on the temperature and the habitability of a planet. Among different physical parameters, some of them, up until now, cannot be determined by any method such as the planet’s spin obliquity, diurnal period, ocean-land ratio, and pressure level. Here we apply this model to study the effect of these unknown parameters on the habitability of three exoplanets located in the inner, outer, and middle of their optimistic HZ. Among the examined parameters, the impact of pressure is more straightforward. It has a nearly direct relation with temperature and also with the habitability in the case of a cold planet. The effect of other parameters is discussed with details. To quantify the impact of all these unknown parameters we utilize a statistical interface which provides us with the conditional probability on habitability status of each planet.

No abstract