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arXiv · 2506.23228

Direct proton transfer on $^{46}$Ar supports the presence of a charge density bubble linked to a novel nuclear structure below $^{48}$Ca

Abstract

The $^{46}$Ar($^3$He,d)$^{47}$K reaction was performed in inverse kinematics using a radioactive $^{46}$Ar beam produced by the SPIRAL1 facility at GANIL and a cryogenic $^{3}$He target. The AGATA-MUGAST-VAMOS setup allowed the coincident measurement of the $γ$ rays, deuterons and recoiling $^{47}$K isotopes produced by the reaction. The relative cross sections towards the proton-addition states in $^{47}$K point towards a depletion of the $πs_{1/2}$ shell. The experimental findings are in good agreement with ab initio calculations, which predict that $^{46}$Ar exhibits a charge density bubble associated with a pronounced proton closed-shell character.

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Daniele Brugnara, Andrea Gottardo, Marlene Assiè, Carlo Barbieri, Daniele Mengoni, Didier Beaumel, Stefano Brolli, Simone Bottoni, Emmanuel Clément, Gianluca Colò, Freddy Flavigny, Franco Galtarossa, Valerian Girard-Alcindor, Antoine Lemasson, Adrien Matta, Diego Ramos, Vittorio Somà, José Javier Valiente-Dobón, Enrico Vigezzi, Mathieu Babo, Diego Barrientos, Dino Bazzacco, Piotr Bednarczyk, Giovanna Benzoni, Yorick Blumenfeld, Helen Boston, Angela Bracco, Bo Cederwall, Michal Ciemala, Ushasi Datta, Giacomo de Angelis, Gilles de France, César Domingo-Pardo, Jérémie Dudouet, José Dueñas, Beatriz Fernandez Domínguez, Andrés Gadea, Alain Goasduff, Vicente González, Fairouz Hammache, Laura Harkness-Brennan, Herbert Hess, Charles Houarner, Andrés Illana, Daniel Judson, Andrea Jungclaus, Wolfram Korten, Marc Labiche, Louis Lalanne, Silvia Leoni, Cyril Lenain, Sylvain Leblond, Joa Ljungvall, Ivano Lombardo, Adam Maj, Naomi Marchini, Roberto Menegazzo, Bénédicte Million, Johan Nyberg, Rosa María Pérez-Vidal, Zsolt Podolyak, Alberto Pullia, Begoña Quintana, Francesco Recchia, Peter Reiter, Kseniia Rezynkina, Marco Rocchini, Frédéric Saillant, Marie-Delphine Salsac, Ángel Miguel Sánchez Benítez, Jennifer Sánchez Rojo, Enrique Sanchis, Menekşe Şenyiğit, Marco Siciliano, John Simpson, Dorottya Sohler, Christophe Theisen, Irene Zanon, Magdalena Zielińska. 2025-07-05. Direct proton transfer on $^{46}$Ar supports the presence of a charge density bubble linked to a novel nuclear structure below $^{48}$Ca. https://arxiv.org/abs/2506.23228

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