A classical field treatment of gravitational fluctuation forces: From the space-time foam to neutron star merger interactions Author: Fabrizio Pinto1 1

In this presentation, we discuss a treatment of Casimir-Polder gravitational fluctuation forces based on a classical general relativistic gravitational field framework. In analogy with the acoustic Casimir effect, we analyze the interaction between high density neutron star surfaces within a bath of classical gravitational waves. We extend a previously published treatment of the interaction of gravitationally polarizable particles within a zero-point gravitational field, also including mixed gravitationalelectrodynamical potentials. Finally, we consider the exploitation of “fluctuations of fluctuation forces” on very short time-scales as possible magnification strategies in the detection of such interactions on an elementary particle scale, such as in neutron-neutron and neutron-wall scattering processes. The epistemological implications of our findings in the search for unique quantum gravity signatures are explored. 546 Fully calibrated lanthanide atomic data for 3D kilonova modeling With the detection of multiple neutron-star merger events in the last few years, the need for a more comprehensive understanding of nuclear and atomic properties has become increasingly important. Despite our current understanding, there are still large discrepancies in the opacities obtained from different codes and methods. These discrepancies lead to variations in the location and strength of absorption and emission features in radiative transfer models and prevent a firm identification of r-process products. To address this issue, we developed an optimisation technique for energy levels and oscillator strengths consistent with available experimental data. With this novel method, we can increase the accuracy of calculations while reducing the computational cost, finally making it possible to apply the method to all lanthanides instead of focusing on single ions. We will report on converged large-scale atomic structure calculations of all singly and doubly ionised lanthanides with greatly improved transition wavelength accuracy compared to previous works. The impact of our new atomic data set on realistic 3D radiative transfer calculations and prospects of rprocess signature identification will be investigated. This work is supported by the European Research Council (ERC) under the European Union’s Horizon2020 research and innovation programme (ERC Advanced Grant KILONOVA No.885281) The Euclid mission: current status, results from early observations, and future prospects / 547 Near Infrared Spectro-Photometer instrument performances and capabilities INAF-OAS ESA’s mission Euclid launched in July 2023 was fully commissioned and since early 2024 is performing its nominal survey. Euclid performs an extra galactic survey (0<z<2) using visible and nearinfrared light. To detect infrared radiation is equipped with the Near-Infrared Spectro-Photometer (NISP) instrument sensible in the 0.9-2 µm range. The NISP instrument will be extensively described, including its complete optical system that allows to perform spectrometry (using a Blue and Red Grisms) and photometry (using YE 0.95-1.21µm, JE 1.17-1.57µm, and HE 1.52-2.02µm filters); its focal plane array (0.56 deg2 FoV) composed of 16 Teledyne’s HAWAII-2RG with a total of 64 Mpx, with a 0.3 arcsec/px resolution; and the data reduction approach implementing with the on-board processing to derive the signal and mitigate the downlinked data load to ground. NISP capabilities will be described using examples of in-flight calibration results that enabled science results already achieved with the early release data what will be partially touch in this presentation