Observation and spectroscopy of proton-unbound nucleus $^{21}$Al

D. Kostyleva; X. -D. Xu; I. Mukha; L. Acosta; M. Bajzek; E. Casarejos; A. A. Ciemny; D. Cortina-Gil; W. Dominik; J. A. Dueñas; J. M. Espino; A. Estradé; F. Farinon; A. Fomichev; H. Geissel; J. Gómez-Camacho; A. Gorshkov; L. V. Grigorenko; Z. Janas; G. Kamiński; O. Kiselev; R. Knöbel; A. A. Korsheninnikov; S. Krupko; M. Kuich; N. Kurz; Yu. A. Litvinov; G. Marquinez-Durán; I. Martel; C. Mazzocchi; E. Yu. Nikolskii; C. Nociforo; A. K. Ordúz; M. Pfützner; S. Pietri; M. Pomorski; A. Prochazka; C. Rodríguez-Tajes; S. Rymzhanova; A. M. Sánchez-Benítez; C. Scheidenberger; H. Simon; B. Sitar; R. Slepnev; M. Stanoiu; P. Strmen; K. Sümmerer; I. Szarka; M. Takechi; Y. K. Tanaka; H. Weick; J. S. Winfield; P. J. Woods; M. V. Zhukov

doi:10.1103/physrevc.110.l031301

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arXiv · 2406.04771

Observation and spectroscopy of proton-unbound nucleus $^{21}$Al

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Abstract

We report on the observation of previously-unknown isotope $^{21}$Al, the first unbound aluminum isotope located beyond the proton dripline. The $^{21}$Al nucleus decays by one-proton (1p) emission, and its in-flight decays were detected by tracking trajectories of all decay products with micro-strip silicon detectors. The 1p-emission processes were studied by analyses of the measured angular correlations of decay products $^{20}$Mg+p. The 1p-decay energies of ground and low-lying excited states of $^{21}$Al, its mass excess and proton separation energy value $S_p$=$-1.1(1)$ MeV were determined.

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D. Kostyleva, X. -D. Xu, I. Mukha, L. Acosta, M. Bajzek, E. Casarejos, A. A. Ciemny, D. Cortina-Gil, W. Dominik, J. A. Dueñas, J. M. Espino, A. Estradé, F. Farinon, A. Fomichev, H. Geissel, J. Gómez-Camacho, A. Gorshkov, L. V. Grigorenko, Z. Janas, G. Kamiński, O. Kiselev, R. Knöbel, A. A. Korsheninnikov, S. Krupko, M. Kuich, N. Kurz, Yu. A. Litvinov, G. Marquinez-Durán, I. Martel, C. Mazzocchi, E. Yu. Nikolskii, C. Nociforo, A. K. Ordúz, M. Pfützner, S. Pietri, M. Pomorski, A. Prochazka, C. Rodríguez-Tajes, S. Rymzhanova, A. M. Sánchez-Benítez, C. Scheidenberger, H. Simon, B. Sitar, R. Slepnev, M. Stanoiu, P. Strmen, K. Sümmerer, I. Szarka, M. Takechi, Y. K. Tanaka, H. Weick, J. S. Winfield, P. J. Woods, M. V. Zhukov. 2024-06-07. Observation and spectroscopy of proton-unbound nucleus $^{21}$Al. https://doi.org/10.1103/physrevc.110.l031301

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