Revisiting the charged kaon mass

The precision of the charged kaon mass is an order of magnitude worse than the precision of the charged pion mass mainly due to two inconsistent measurements. We plan to improve this precision by determining the charged kaon mass with the requested accuracy in the measurements of X-ray transitions in kaonic atoms of selected solid targets with the HPGe detector at DAΦNE in Laboratori Nazionali di Frascati, Italy. The measurements will be performed in parallel with SIDDHARTA-2 measurements of X-ray transitions in gaseous targets. The status of the preparation of the measurements will be presented

Novel Machine Learning and Differentiable Programming Techniques applied to the VIP-2 Underground Experiment

In this work, we present novel Machine Learning and Differentiable Programming enhanced calibration techniques used to improve the energy resolution of the Silicon Drift Detectors (SDDs) of the VIP-2 underground experiment at the Gran Sasso National Laboratory (LNGS). We achieve for the first time a Full Width at Half Maximum (FWHM) in VIP-2 below 180 eV at 8 keV, improving around 10 eV on the previous state-of-the-art. SDDs energy resolution is a key parameter in the VIP-2 experiment, which is dedicated to searches for physics beyond the standard quantum theory, targeting Pauli Exclusion Principle (PEP) violating atomic transitions. Additionally, we show that this method can correct for potential miscalibrations, requiring less fine-tuning with respect to standard methods.Comment: Submitted to Measurement Science and Technolog

Towards the first kaonic deuterium measurement with the SIDDHARTA-2 experiment at DAΦNE

The SIDDHARTA-2 experiment is going to perform the longawaited high precision X-ray measurement of kaonic deuterium, obtaining for the first time the values of the shift and the width induced by the strong interaction on the fundamental level. By combining this unprecedented result with the analogous kaonic hydrogen measurement performed by the SIDDHARTA experiment, it will be possible to extract the isospin-dependent antikaon-nucleon scattering lengths, providing direct information on the Quantum Chromodynamics (QCD) in the non-perturbative Chromodynamics (QCD) in the non-perturbative regime in the strangeness sector. This paper describes the SIDDHARTA-2 experiment, presently installed at the DAΦNE collider of Istituto Nazionale di Fisica Nucleare-Laboratori Nazionali di Frascati, and the results obtained during the kaonic helium run, preparatory for the kaonic deuterium data taking campaign planned for 2022

TESTING THE PAULI EXCLUSION PRINCIPLE IN THE COSMIC SILENCE

The VIP Collaboration is performing high precision tests of the Pauli Exclusion Principle for electrons in the extremely low cosmic background environment of the Underground Gran Sasso Laboratories of INFN (Italy). The experimental technique consists in introducing a DC current in a copper conductor, searching for K$_{\alpha}$ PEP-forbidden atomic transitions when the K shell is already occupied by two electrons. VIP set an upper limit on the PEP-violation probability $\frac{1}{2} \beta^2 < 4.7 \times 10^{-29}$. The aim of the upgraded VIP-2 experiment is to improve this result at least by two orders of magnitude. The improved experimental setup and the results of a preliminary data analysis, corresponding to the the first run of the VIP-2 data taking (2016–2017), will be presented

VIP2 in LNGS - Testing the Pauli Exclusion Principle for electrons with high sensitivity

The VIP2 (VIolation of the Pauli Exclusion Principle) experiment at the Gran Sasso underground laboratory (LNGS) is searching for possible violations of standard quantum mechanics predictions in atoms at very high sensitivity. We investigate atomic transitions with precision X-ray spectroscopy in order to test the Pauli Exclusion Principle (PEP) and therefore the related spin-statistics theorem. We will present our experimental method for the search for "anomalous" (i.e. Pauli-forbidden) X-ray transitions in copper atoms, produced by "new" electrons, which could have tiny probability to undergo Pauli-forbidden transition to the ground state already occupied by two electrons. We will describe the VIP2 experimental setup, which is taking data at LNGS presently. The goal of VIP2 is to test the PEP for electrons with unprecedented accuracy, down to a limit in the probability that PEP is violated at the level of 10−31. We will present current experimental results and discuss implications of a possible violation

Characterization of the SIDDHARTA-2 luminosity monitor

A luminosity monitor, based on plastic scintillator detectors, has been developed for the SIDDHARTA-2 experiment aiming to perform high precision measurements of kaonic atoms and was installed in 2020 on the DAFNE $e^+e^-$ collider at LNF (Laboratori Nazionali di Frascati, INFN). The main goal of this system is to provide the~instantaneous and integrated luminosity of the DAFNE facility by measuring the rate of $K^+K^-$ correlated pairs emitted by the phi meson decay. This task requires an accurate timing of the DAQ signals, as well as timing resolution below 1ns, in order to disentangle the $K^\pm$ signals from the background minimum ionizing particles (MIPs) produced during the $e^+e^-$ collisions at DAFNE. In this paper the luminosity monitor concept as well as its laboratory characterization and the first results inside DAFNE are presented.Comment: Published in JINS

A new kaonic helium measurement in gas by SIDDHARTINO at the DAFNE collider*

The SIDDHARTINO experiment at the DA{\Phi}NE Collider of INFN-LNF, the pilot run for the SIDDHARTA-2 experiment which aims to perform the measurement of kaonic deuterium transitions to the fundamental level, has successfully been concluded. The paper reports the main results of this run, including the optimization of various components of the apparatus, among which the degrader needed to maximize the fraction of kaons stopped inside the target, through measurements of kaonic helium transitions to the 2p level. The obtained shift and width values are {\epsilon}_2p = E_exp-E_e.m = 0.2 {\pm} 2.5(stat) {\pm} 2(syst) eV and {\Gamma}_2p = 8 {\pm} 10 eV (stat), respectively. This new measurement of the shift, in particular, represents the most precise one for a gaseous target and is expected to contribute to a better understanding of the kaon-nuclei interaction at low energy