Phase Transition in the SRG Flow of Nuclear Interactions

Autor(es)

Timoteo, V. S. ; Ruiz Arriola, E. ; Szpigel, S.

• Tipo de documento: Artigo Científico
• Fonte: FEW-BODY SYSTEMS; v. 58, n. 2 MAR 2017.
• Citações Web of Science: 0

Resumo

We use a chiral interaction at N3LO in the (1)S0 channel of the nucleon-nucleon interaction in order to investigate the on-shell transition along the similarity renormalization group flow towards the infrared limit. We find a crossover at a scale that depends on the number of grid points used to discretise the momentum space. One of the most appealing features of nature is universality. Some phenomena disguise themselves across many different areas where physical systems are described by sometimes unrelated theories or models. Yet they appear recurrently in some form. An excellent example is the phase transition resulting from a broken symmetry. It is observed in magnetism when the temperature of a spin chain in a two-dimensional Ising model crosses a critical value {[}1]. It appears in nuclear physics when observing rotational spectra of deformed nuclei {[}2] and it is also present in hadron physics when the coupling between quarks in a two-flavour NJL model exceeds a critical value {[}3]. In both magnetism and nuclear physics the phase transition results from the breaking of the rotational symmetry and the corresponding Goldstone bosons are spin waves and nuclear rotation. In hadron physics the phase transition results from the chiral symmetry breaking and the corresponding Goldstone boson is the pion. This phenomenon is shown in Fig. 1 for both two-dimensional Ising model (left) and two-flavour NJL model (right). In this work we report on a similar and remarkable phase transition observed in the similarity renormalization group flow, which is used to change and calibrate the resolution scale of nuclear interactions to their natural values in different applications. The evolution of an NN interaction with the SRG {[}4] is performed by numerically integrating the Wegner renormalization group flow equation for the potential matrix {[}GRAPHICS] (AU)

• Processo FAPESP: 16/07061-3 - Teorias efetivas em sistemas hadrônicos de poucos e muitos corpos
• Beneficiário: Varese Salvador Timoteo
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 16/05554-2 - 23rd European Conference on Few-Body Problems in Physics
• Beneficiário: Varese Salvador Timoteo
• Modalidade de apoio: Auxílio à Pesquisa - Reunião - Exterior