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Title: Properties of infrared extrapolations in a harmonic oscillator basis

Here, the success and utility of effective field theory (EFT) in explaining the structure and reactions of few-nucleon systems has prompted the initiation of EFT-inspired extrapolations to larger model spaces in ab initio methods such as the no-core shell model (NCSM). In this contribution, we review and continue our studies of infrared (ir) and ultraviolet (uv) regulators of NCSM calculations in which the input is phenomenological NN and NNN interactions fitted to data. We extend our previous findings that an extrapolation in the ir cutoff with the uv cutoff above the intrinsic uv scale of the interaction is quite successful, not only for the eigenstates of the Hamiltonian but also for expectation values of operators, such as r 2, considered long range. The latter results are obtained with Hamiltonians transformed by the similarity renormalization group (SRG) evolution. On the other hand, a possible extrapolation of ground state energies in the uv cutoff when the ir cutoff is below the intrinsic ir scale is not robust and does not agree with the ir extrapolation of the same data or with independent calculations using other methods.
 [1] ;  [2]
  1. Univ. of Arizona, Tucson, AZ (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0218-3013
Grant/Contract Number:
AC52-07NA27344; FG02-04ER41338
Accepted Manuscript
Journal Name:
International Journal of Modern Physics E
Additional Journal Information:
Journal Volume: 25; Journal Issue: 05; Journal ID: ISSN 0218-3013
World Scientific
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
Country of Publication:
United States
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; no-core shell model; convergence of expansion in harmonic oscillator functions; ultraviolet regulator; infrared regulator
OSTI Identifier: