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Pairing effect on the giant dipole resonance width at low temperature

Nguyen Dinh Dang·Akito Arima
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Abstract

The width of the giant dipole resonance (GDR) at finite temperature T in Sn-120 is calculated within the Phonon Damping Model including the neutron thermal pairing gap determined from the modified BCS theory. It is shown that the effect of thermal pairing causes a smaller GDR width at T below 2 MeV as compared to the one obtained neglecting pairing. This improves significantly the agreement between theory and experiment including the most recent data point at T = 1 MeV.

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Nguyen Dinh Dang, Akito Arima. 2003-09-05. Pairing effect on the giant dipole resonance width at low temperature. https://doi.org/10.1103/physrevc.68.044303

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