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Structure of $^{43}$P and $^{42}$Si in a two-level shape-coexistence model

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 نشر من قبل Augusto Macchiavelli
 تاريخ النشر 2021
  مجال البحث
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Exclusive cross sections for the $^{43}$P$(-1p)^{42}$Si reaction to the lowest $0^+$ and $2^+$ states, measured at NSCL with GRETINA and the S800, are interpreted in terms of a two-level mixing (collective) model of oblate and prolate co-existing shapes. Using the formalism developed for deformed nuclei we calculate the spectroscopic amplitudes and exclusive cross-sections in the strong coupling limit, where for $^{43}$P the schematic wavefunction includes the coupling of the Nilsson [211]$frac{1}{2}$ proton orbit. Good agreement with the experimental data is obtained when the amplitude of the oblate configuration is $gtrsim$ 80%, suggesting that both nuclei are predominantly oblate, in line with theoretical expectations.

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