Nuclear mass radius and pressure in the Skyrme model

We compute the mass radius, scalar radius, tensor radius, baryon number radius, and mechanical radius of nuclei with baryon number <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mi>B</a:mi><a:mo>=</a:mo><a:mn>1</a:mn><a:mo>,</a:mo><a:mn>2</a:mn><a:mo>,</a:mo><a:mn>3</a:mn><a:mo>,</a:mo><a:mn>4</a:mn><a:mo>,</a:mo><a:mn>5</a:mn><a:mo>,</a:mo><a:mn>6</a:mn><a:mo>,</a:mo><a:mn>7</a:mn><a:mo>,</a:mo><a:mn>8</a:mn></a:mrow></a:math>, 32, 108 in the Skyrme model. The relations between these radii and the nuclear gravitational form factors are investigated. We also compute the ‘pressure’ distribution and find that it is negative in the core region for all the nuclei with <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mi>B</c:mi><c:mo>></c:mo><c:mn>1</c:mn></c:math>. This suggests that the way mechanical stability is achieved in nuclei is qualitatively different than in the nucleon.