Stability of the heaviest elements: <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>K</mml:mi></mml:math> isomer in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>No</mml:mi><mml:mprescripts/><mml:none/><mml:mn>250</mml:mn></mml:mmultiscripts></mml:math>
J. Kallunkathariyil, B. Sulignano, P. T. Greenlees, J. Khuyagbaatar, Ch. Theisen, K. Auranen, H. Badran, F. Defranchi Bisso, P. Brionnet, R. Briselet, A. Drouart, Z. Favier, T. Goigoux, T. Grahn, K. Hauschild, A. Herzáň, F. P. Heßberger, U. Jakobsson, R. Julin, S. Juutinen, J. Konki, M. Leino, A. Lightfoot, J. Pakarinen, P. Papadakis, J. Partanen, P. Peura, P. Rahkila, K. Rezynkina, P. Ruotsalainen, M. Sandzelius, J. Sarén, C. Scholey, M. Siciliano, J. Sorri, S. Stolze, A. I. Svirikhin, J. Uusitalo, M. Vandebrouck, A. Ward, C. Wraith, M. Zielińska
Abstract
Decay spectroscopy of ${}^{250}$No, aided by digital pulse-shape analysis, is reported and identifies this nucleus to be one of the rare breed of very heavy nuclei with an isomeric state living considerably longer than its ground state. This phenomenon has interesting consequences for nuclear structure models aiming to determine the borders of the island of stability of superheavy elements.