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Harmonic-Oscillator-Based Effective Theory

W. C. Haxton
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Abstract

I describe harmonic-oscillator-based effective theory (HOBET) and explore the extent to which the effects of excluded higher-energy oscillator shells can be represented by a contact-gradient expansion in next-to-next-to-leading order (NNLO). I find the expansion can be very successful provided the energy dependence of the effective interaction, connected with missing long-wavelength physics associated with low-energy breakup channels, is taken into account. I discuss a modification that removes operator mixing from HOBET, simplifying the task of determining the parameters of an NNLO interaction.

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W. C. Haxton. 2006-08-06. Harmonic-Oscillator-Based Effective Theory. https://doi.org/10.1142/9789812708250_0013

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