Abstract
Nuclear pasta topology is an essential ingredient to determine transport properties in the inner crust of neutron stars. We perform semiclassical molecular dynamics simulations of nuclear pasta for proton fractions Yp=0.30 and Yp=0.40 near one-third of nuclear saturation density, n=0.05fm-3, at a temperature T=1.0MeV. Our simulations are, to our knowledge, the largest nuclear pasta simulations to date and contain up to 3276800 nucleons in the Yp=0.30 and 819200 nucleons in the Yp=0.40 case. An algorithm to determine which nucleons are part of a given sub-domain in the system is presented. By comparing runs of different sizes we study finite-size effects, equilibration time, the formation of multiple domains and defects in the pasta structures, as well as the structure factor dependence on simulation size. Although we find qualitative agreement between the topological structure and the structure factors of runs with 51 200 nucleons and those with 819200 nucleons or more, we show that simulations with hundreds of thousands of nucleons may be necessary to accurately predict pasta transport properties.
| Original language | English |
|---|---|
| Article number | 055801 |
| Journal | Physical Review C |
| Volume | 98 |
| Issue number | 5 |
| DOIs | |
| State | Published - 7 Nov 2018 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2018 American Physical Society.
Funding
We thank Greg Huber (KITP) and Kris Delaney (UCSB) for interesting and useful discussions regarding polymer topology and their similarities to nuclear pasta. We also thank William Newton (TAMU-Commerce) for sharing his insights on nuclear pasta domains, and Gerardo Ortiz (IU Bloomington) and Andrey Chugunov (IOFFE Institute St. Petersburg) for suggestions that helped improve this paper considerably. A.S.S. was supported in part by the Conselho Nacional de Desenvolvimento CientÃ-fico e TecnolÃgico (201432/2014-5) and in part by the National Science Foundation under Award No. AST-1333520 and CAREER PHY-1151197. M.E.C. is supported by a fellowship from Canadian Institute for Theoretical Astrophysics. This research was supported in part by DOE Grants No. DE-FG02-87ER40365 (Indiana University) and No. DE-SC0018083 (NUCLEI SciDAC-4 Collaboration), and in part by Lilly Endowment, Inc., through its support for the Indiana University Pervasive Technology Institute, and in part by the Indiana METACyt Initiative. The Indiana METACyt Initiative at IU is also supported in part by Lilly Endowment, Inc. This research used resources of the Oak Ridge Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE-AC05-00OR22725. We thank Greg Huber (KITP) and Kris Delaney (UCSB) for interesting and useful discussions regarding polymer topology and their similarities to nuclear pasta. We also thank William Newton (TAMU-Commerce) for sharing his insights on nuclear pasta domains, and Gerardo Ortiz (IU Bloomington) and Andrey Chugunov (IOFFE Institute St. Petersburg) for suggestions that helped improve this paper considerably. A.S.S. was supported in part by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (201432/2014-5) and in part by the National Science Foundation under Award No. AST-1333520 and CAREER PHY-1151197. M.E.C. is supported by a fellowship from Canadian Institute for Theoretical Astrophysics. This research was supported in part by DOE Grants No. DE-FG02-87ER40365 (Indiana University) and No. DE-SC0018083 (NUCLEI SciDAC-4 Collaboration), and in part by Lilly Endowment, Inc., through its support for the Indiana University Pervasive Technology Institute, and in part by the Indiana METACyt Initiative. The Indiana METACyt Initiative at IU is also supported in part by Lilly Endowment, Inc. This research used resources of the Oak Ridge Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE-AC05-00OR22725.
| Funders | Funder number |
|---|---|
| Indiana METACyt Initiative | |
| Indiana University Pervasive Technology Institute | |
| Lilly Endowment, Inc. | |
| National Science Foundation | PHY-1151197, AST-1333520 |
| U.S. Department of Energy | DE-SC0018083, DE-FG02-87ER40365 |
| Directorate for Mathematical and Physical Sciences | 1151197, 1333520 |
| Office of Science | DE-AC05-00OR22725 |
| Indiana University | |
| Lilly Endowment | |
| Canadian Institute for Theoretical Astrophysics | |
| Conselho Nacional de Desenvolvimento Científico e Tecnológico | 201432/2014-5 |
| National Science Foundation |