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arXiv · 1503.07144

Infrared length scale and extrapolations for the no-core shell model

K. A. Wendt·C. Forssén·T. Papenbrock·D. Sääf
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Abstract

We precisely determine the infrared (IR) length scale of the no-core shell model (NCSM). In the NCSM, the $A$-body Hilbert space is truncated by the total energy, and the IR length can be determined by equating the intrinsic kinetic energy of $A$ nucleons in the NCSM space to that of $A$ nucleons in a $3(A-1)$-dimensional hyper-radial well with a Dirichlet boundary condition for the hyper radius. We demonstrate that this procedure indeed yields a very precise IR length by performing large-scale NCSM calculations for $^{6}$Li. We apply our result and perform accurate IR extrapolations for bound states of $^{4}$He, $^{6}$He, $^{6}$Li, $^{7}$Li. We also attempt to extrapolate NCSM results for $^{10}$B and $^{16}$O with bare interactions from chiral effective field theory over tens of MeV.

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K. A. Wendt, C. Forssén, T. Papenbrock, D. Sääf. 2015-06-19. Infrared length scale and extrapolations for the no-core shell model. https://doi.org/10.1103/physrevc.91.061301

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