Analytic closures for M1 neutrino transport
Carefully accounting for neutrino transport is an essential component of many astrophysical studies. Solving the full transport equation is too expensive for most realistic applications, especially those involving multiple spatial dimensions. For such cases, resorting to approximations is often the only viable option for obtaining solutions. One such approximation, which recently became popular, is the M1 method. It utilizes the system of the lowest two moments of the transport equation and closes the system with an ad hoc closure relation. The accuracy of the M1 solution depends on the quality of the closure. Several closures have been proposed in the literature and have been used in various studies. We carry out an extensive study of these closures by comparing the results of M1 calculations with precise Monte Carlo calculations of the radiation field around spherically symmetric protoneutron star models. We find that no closure performs consistently better or worse than others in all cases. The level of accuracy that a given closure yields depends on the matter configuration, neutrino type and neutrino energy. As a result, given this limitation, the maximum entropy closure by Minerbo on average yields relatively accurate results in the broadest set of cases considered in thismore »
 Authors:

^{[1]};
^{[2]};
^{[3]}
 California Inst. of Technology (CalTech), Pasadena, CA (United States)
 Nazarbayev Univ., Astana (Kazakhstan)
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Publication Date:
 Report Number(s):
 LAUR1720390
Journal ID: ISSN 00358711; TRN: US1702448
 Grant/Contract Number:
 AC5206NA25396
 Type:
 Accepted Manuscript
 Journal Name:
 Monthly Notices of the Royal Astronomical Society
 Additional Journal Information:
 Journal Volume: 469; Journal Issue: 2; Journal ID: ISSN 00358711
 Publisher:
 Royal Astronomical Society
 Research Org:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org:
 Universities/Institutions; USDOE
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTRONOMY AND ASTROPHYSICS; hydrodynamics, neutrinos, radiative transfer, stars: evolution, stars: neutron, stars: supernovae
 OSTI Identifier:
 1358170
Murchikova, E. M., Abdikamalov, E., and Urbatsch, T.. Analytic closures for M1 neutrino transport. United States: N. p.,
Web. doi:10.1093/mnras/stx986.
Murchikova, E. M., Abdikamalov, E., & Urbatsch, T.. Analytic closures for M1 neutrino transport. United States. doi:10.1093/mnras/stx986.
Murchikova, E. M., Abdikamalov, E., and Urbatsch, T.. 2017.
"Analytic closures for M1 neutrino transport". United States.
doi:10.1093/mnras/stx986. https://www.osti.gov/servlets/purl/1358170.
@article{osti_1358170,
title = {Analytic closures for M1 neutrino transport},
author = {Murchikova, E. M. and Abdikamalov, E. and Urbatsch, T.},
abstractNote = {Carefully accounting for neutrino transport is an essential component of many astrophysical studies. Solving the full transport equation is too expensive for most realistic applications, especially those involving multiple spatial dimensions. For such cases, resorting to approximations is often the only viable option for obtaining solutions. One such approximation, which recently became popular, is the M1 method. It utilizes the system of the lowest two moments of the transport equation and closes the system with an ad hoc closure relation. The accuracy of the M1 solution depends on the quality of the closure. Several closures have been proposed in the literature and have been used in various studies. We carry out an extensive study of these closures by comparing the results of M1 calculations with precise Monte Carlo calculations of the radiation field around spherically symmetric protoneutron star models. We find that no closure performs consistently better or worse than others in all cases. The level of accuracy that a given closure yields depends on the matter configuration, neutrino type and neutrino energy. As a result, given this limitation, the maximum entropy closure by Minerbo on average yields relatively accurate results in the broadest set of cases considered in this work.},
doi = {10.1093/mnras/stx986},
journal = {Monthly Notices of the Royal Astronomical Society},
number = 2,
volume = 469,
place = {United States},
year = {2017},
month = {4}
}