The ρ(770) meson is the most extensively studied resonance in lattice QCD simulations in two (N f = 2) and three (N f = 2 + 1) flavor formulations. We analyze N f = 2 lattice scattering data using unitarized Chiral Perturbation Theory, allowing not only for the extrapolation in mass but also in flavor, N f = 2 → N f = 2 + 1. The flavor extrapolation requires information from a global fit to ππ and πK phase shifts from experiment. While the chiral extrapolation of N f = 2 lattice data leads to masses of the ρ(770) meson far below the experimental one, we find that the missing KK channel is able to explain this discrepancy.

We study the two step sequential one pion production mechanism, $np(I=0)\to \pi^-pp$, followed by the fusion reaction $pp\to \pi^+d$, in order to describe the $np\to \pi^+\pi^-d$ reaction with $\pi^+\pi^-$ in $I=0$, where a narrow peak, so far identified with a ``$d(2380)$'' dibaryon, has been observed. We find that the second step $pp\to \pi^+d$ is driven by a triangle singularity that determines the position of the peak of the reaction and the large strength of the cross section. The combined cross section of these two mechanisms produce a narrow peak with the position, width and strength compatible with the experimental observation within the approximations done. This novel interpretation of the peak without invoking a dibaryon explains why the peak is not observed in other reactions where it has been searched for.

In a precision era of hadron spectroscopy, new tools are required for the analysis of data from hadron reactions. In this talk, we show an analysis of low-energy neutral pion photoproduction data using the Least Absolute Shrinkage and Selection Operator (LASSO) in combination with criteria from information theory and K-fold cross validation. These analysis techniques will become relevant in the near future. First, we illustrate these methods with synthetic data; then, the latest available measurements of differential cross sections (dσ /dΩ), photon-beam asymmetries (Σ), and target asymmetry differential cross sections (dσ T /d ≡ T dσ /dΩ) in the low-energy regime, are analyzed, and its feasibility for real data is demonstrated.

In this talk we show that the two-step sequential one pion production mechanism, np(I = 0) → π −pp, followed by the fusion reaction pp → π +d, can explain the narrow peak identified with a “d ∗ (2380)” dibaryon in the np → π +π −d reaction with π +π − in I = 0. We demonstrate that the second step pp → π +d is driven by a triangle singularity that determines the position of the peak of the reaction and the large strength of the cross section. The combined cross section of these two mechanisms produce a narrow peak with the position, width and strength compatible with the experimental observation within the approximations done. This novel interpretation of the peak without invoking a dibaryon explains why the peak is not observed in other reactions where it has been searched for.

Este artículo presenta Proyecto Meitner como una acción de divulgación científica diseñada para abordar, entre otras cuestiones, la problemática de las mujeres en Física a través de las artes escénicas. Se presenta, también, un estudio de sesgos y estereotipos de género en ciencia realizado al alumnado de los centros de secundaria de la Comunitat Valenciana que participaron en dos sesiones matinales de la obra de teatro Proyecto Meitner. Se utilizó un cuestionario que rellenaron 134 estudiantes estudiantes antes de las funciones. Las respuestas revelan una perpetuación de los estereotipos asociados al personal científico, definido principalmente como muy inteligente, culto, occidental, hombre, mayor, solitario y con bata. Además, el alumnado encuestado cree que los chicos tienen mejores aptitudes que las chicas para las carreras universitarias aun cuando las capacidades en ambos casos  son las mismas.