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DOE OSTI · 2000280

Surprising Charge-Radius Kink in the Sc Isotopes at N = 20

König, Kristian·Fritzsche, Stephan·Hagen, Gaute·Holt, Jason D.·Klose, Andrew·Lantis, Jeremy·Liu, Yuan·Minamisono, Kei·Miyagi, Takayuki·Nazarewicz, Witold·Papenbrock, Thomas·Pineda, Skyy V.·Powel, Robert·Reinhard, Paul-Gerhard
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Abstract

For this work, charge radii of neutron deficient 40 Sc and 41 Sc nuclei were determined using collinear laser spectroscopy. With the new data, the chain of Sc charge radii extends below the neutron magic number N=20 and shows a pronounced kink, generally taken as a signature of a shell closure, but one notably absent in the neighboring Ca, K, and Ar isotopic chains. Theoretical models that explain the trend at N=20 for the Ca isotopes cannot reproduce this puzzling behavior.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSnuclear radiinuclear structure & decaysradioactive beamsspectrometersspectroscopic techniques

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König, Kristian, Fritzsche, Stephan, Hagen, Gaute, Holt, Jason D., Klose, Andrew, Lantis, Jeremy, Liu, Yuan, Minamisono, Kei, Miyagi, Takayuki, Nazarewicz, Witold, Papenbrock, Thomas, Pineda, Skyy V., Powel, Robert, Reinhard, Paul-Gerhard. 2023-09-05. Surprising Charge-Radius Kink in the Sc Isotopes at N = 20. https://doi.org/10.1103/physrevlett.131.102501

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