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Title: An Expanded Set of Los Alamos OPLIB Tables in MESA: Type-1 Rosseland-mean Opacities and Solar Models
Abstract We present a set of 1194 Type-1 Rosseland-mean opacity tables for four different metallicity mixtures. These new Los Alamos OPLIB atomic radiative opacity tables are an order of magnitude larger in number than any previous opacity table release, and span regimes where previous opacity tables have not existed. For example, the new set of opacity tables expands the metallicity range toZ= 10−6toZ= 0.2, which allows improved accuracy of opacities at low and high metallicity, increases the table density in the metallicity rangeZ= 10−4toZ= 0.1 to enhance the accuracy of opacities drawn from interpolations across neighboring metallicities, and adds entries for hydrogen mass fractions betweenX= 0 andX= 0.1 includingX= 10−2, 10−3, 10−4, 10−5, 10−6that can improve stellar models of hydrogen deficient stars. We implement these new OPLIB radiative opacity tables inMESAand find that calibrated solar models agree broadly with previously published helioseismic and solar neutrino results. We find differences between using the new 1194 OPLIB opacity tables and the 126 OPAL opacity tables range from ≈20% to 80% across individual chemical mixtures, up to ≈8% and ≈15% at the bottom and top of the solar convection zone respectively, and ≈7% in the solar core. We also find differences between standard solar models using different opacity table sources that are on par with altering the initial abundance mixture. We conclude that this new, open-access set of OPLIB opacity tables does not solve the solar modeling problem, and suggest the investigation of physical mechanisms other than the atomic radiative opacity.  more » « less
Award ID(s):
1927130
PAR ID:
10543932
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
IOP
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
968
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
56
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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