Origin of Low- and High-Energy Monopole Collectivity in ¹³²Sn

• Main Authors: Nikolay N. Arsenyev, Alexey P. Severyukhin
• Format: Article
• Language: English
• Published: MDPI AG 2021-05-01
• Series: Universe
• Subjects: collective levels; giant resonances; nuclear density functional theory
• Online Access: https://www.mdpi.com/2218-1997/7/5/145

Beginning with the Skyrme interaction, we study the properties of the isoscalar giant monopole resonances (ISGMR) of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow></mrow><mn>132</mn></msup></semantics></math></inline-formula>Sn. Using the finite-rank separable approximation for the particle-hole interaction, the coupling between one- and two-phonon terms in the wave functions of excited states is taken into account in very large configurational spaces. The inclusion of the phonon–phonon coupling (PPC) results in the formation of a low-energy <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mn>0</mn><mo>+</mo></msup></semantics></math></inline-formula> state. The PPC inclusion leads to a fragmentation of the ISGMR strength to lower energy states and also to a higher energy tail. Using the same set of parameters, we describe the available experimental data for the ISGMR characteristics of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow></mrow><mrow><mn>118</mn><mo>,</mo><mn>120</mn><mo>,</mo><mn>122</mn><mo>,</mo><mn>124</mn></mrow></msup></semantics></math></inline-formula>Sn and give a prediction for <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow></mrow><mrow><mn>126</mn><mo>,</mo><mn>128</mn><mo>,</mo><mn>130</mn><mo>,</mo><mn>132</mn></mrow></msup></semantics></math></inline-formula>Sn.