Improving 1D stellar atmosphere models with insights from multi-dimensional simulations: I. 1D versus 2D stratifications and spectral comparisons for O stars

Context. The outer layers and the spectral appearance of massive stars are inherently affected by radiation pressure. Recent multidimensional, radiation-hydrodynamical (RHD) simulations of massive stellar atmospheres have shed new light on the complexity involved in the surface layers and the onset...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: González i Torà, Gemma (VerfasserIn) , Sander, Andreas A. C. (VerfasserIn) , Sundqvist, Jon (VerfasserIn) , Debnath, D. (VerfasserIn) , Delbroek, L. (VerfasserIn) , Josiek, Joris (VerfasserIn) , Lefever, Roel (VerfasserIn) , Moens, N. (VerfasserIn) , Sijpt, C. Van der (VerfasserIn) , Verhamme, Olivier (VerfasserIn)
Dokumenttyp: Article (Journal)
Sprache:Englisch
Veröffentlicht: February 2025
In: Astronomy and astrophysics
Year: 2025, Jahrgang: 694, Pages: 1-19
ISSN:1432-0746
DOI:10.1051/0004-6361/202452241
Online-Zugang:Verlag, kostenfrei, Volltext: https://doi.org/10.1051/0004-6361/202452241
Verlag, kostenfrei, Volltext: https://www.aanda.org/articles/aa/abs/2025/02/aa52241-24/aa52241-24.html
Volltext
Verfasserangaben:G. González-Torà, A.A.C. Sander, J.O. Sundqvist, D. Debnath, L. Delbroek, J. Josiek, R.R. Lefever, N. Moens, C. Van der Sijpt, and O. Verhamme

MARC

LEADER 00000caa a2200000 c 4500
001 1932407324
003 DE-627
005 20250805150046.0
007 cr uuu---uuuuu
008 250804s2025 xx |||||o 00| ||eng c
024 7 |a 10.1051/0004-6361/202452241  |2 doi 
035 |a (DE-627)1932407324 
035 |a (DE-599)KXP1932407324 
040 |a DE-627  |b ger  |c DE-627  |e rda 
041 |a eng 
084 |a 29  |2 sdnb 
100 1 |a González i Torà, Gemma  |e VerfasserIn  |0 (DE-588)1338011979  |0 (DE-627)1897887434  |4 aut 
245 1 0 |a Improving 1D stellar atmosphere models with insights from multi-dimensional simulations  |b I. 1D versus 2D stratifications and spectral comparisons for O stars  |c G. González-Torà, A.A.C. Sander, J.O. Sundqvist, D. Debnath, L. Delbroek, J. Josiek, R.R. Lefever, N. Moens, C. Van der Sijpt, and O. Verhamme 
264 1 |c February 2025 
300 |b Diagramme 
300 |a 19 
336 |a Text  |b txt  |2 rdacontent 
337 |a Computermedien  |b c  |2 rdamedia 
338 |a Online-Ressource  |b cr  |2 rdacarrier 
500 |a Gesehen am 04.08.2024 
520 |a Context. The outer layers and the spectral appearance of massive stars are inherently affected by radiation pressure. Recent multidimensional, radiation-hydrodynamical (RHD) simulations of massive stellar atmospheres have shed new light on the complexity involved in the surface layers and the onset of radiation-driven winds. These findings include the presence of sub-surface, radiatively driven turbulent motion. For some regimes, the velocities associated with this turbulence and their localisation significantly exceed earlier estimates drawn from stellar structure models. This prompts the question of whether spectral diagnostics obtained with the typical assumptions in 1D spherically symmetric and stationary atmospheres are still sufficient. Aims. For the foreseeable future, the inherent computation costs and necessary approximations will pose challenges to the common usage of multi-dimensional, time-dependent atmosphere models in the quantitative spectral analysis of populations of stars. Therefore, suitable approximations of multi-dimensional simulation results need to be implemented into 1D atmosphere models. Methods. We compared current 1D and multi-dimensional atmosphere modelling approaches to understand their strengths and shortcomings. We calculated the averaged stratifications from selected multi-dimensional calculations for O stars - corresponding to spectral types O8, O4, and O2, with log ∼ 3.7 - to approximate them with 1D stellar atmosphere models using the PoWR model atmosphere code and assuming a fixed β−law for the wind regime. We then studied the effects of our approximations and assumptions on current spectral diagnostics. In particular, we focus on the impact of an additional turbulent pressure in the subsonic layers of the 1D models. Results. To match the 2D averages, the 1D stellar atmosphere models need to account for turbulent pressure in the hydrostatic equation. Moreover, an adjustment of the connection point between the (quasi)hydrostatic regime and the wind regime is required. The improvement between the density stratification of the 1D model and 2D average can be further increased if the mass-loss rate of the 1D model is not identical to that of the 2D simulation; rather, it is typically ∼0.2 dex higher. Especially in the case of an early-type star, this would imply a significantly more extended envelope with a lower effective temperature. Conclusions. Already, the inclusion of a constant turbulence term in the solution of the hydrostatic equation is shown to sufficiently reproduce the 2D-averaged model density stratifications. The addition of a significant turbulent motion also smoothens the slope of the radiative acceleration term in the (quasi)hydrostatic domain, with several potential implications on the total mass-loss rate inferred from 1D modelling. Concerning the spectral synthesis, the addition of a turbulence term in the hydrostatic equation mimics the effect of a lower surface gravity, potentially presenting a solution to the ‘mass discrepancy problem’ between the evolutionary and spectroscopy mass determinations. 
700 1 |a Sander, Andreas A. C.  |e VerfasserIn  |0 (DE-588)1083288482  |0 (DE-627)847936775  |0 (DE-576)455682348  |4 aut 
700 1 |a Sundqvist, Jon  |d 1980-  |e VerfasserIn  |0 (DE-588)143680277  |0 (DE-627)653848331  |0 (DE-576)338342214  |4 aut 
700 1 |a Debnath, D.  |e VerfasserIn  |4 aut 
700 1 |a Delbroek, L.  |e VerfasserIn  |4 aut 
700 1 |a Josiek, Joris  |e VerfasserIn  |0 (DE-588)1342551281  |0 (DE-627)190305379X  |4 aut 
700 1 |a Lefever, Roel  |e VerfasserIn  |0 (DE-588)1294988026  |0 (DE-627)1851790195  |4 aut 
700 1 |a Moens, N.  |e VerfasserIn  |4 aut 
700 1 |a Sijpt, C. Van der  |e VerfasserIn  |4 aut 
700 1 |a Verhamme, Olivier  |e VerfasserIn  |0 (DE-588)1368275230  |0 (DE-627)1927857872  |4 aut 
773 0 8 |i Enthalten in  |t Astronomy and astrophysics  |d Les Ulis : EDP Sciences, 1969  |g 694(2025) vom: Feb., Artikel-ID A269, Seite 1-19  |h Online-Ressource  |w (DE-627)253390222  |w (DE-600)1458466-9  |w (DE-576)072283351  |x 1432-0746  |7 nnas  |a Improving 1D stellar atmosphere models with insights from multi-dimensional simulations I. 1D versus 2D stratifications and spectral comparisons for O stars 
773 1 8 |g volume:694  |g year:2025  |g month:02  |g elocationid:A269  |g pages:1-19  |g extent:19  |a Improving 1D stellar atmosphere models with insights from multi-dimensional simulations I. 1D versus 2D stratifications and spectral comparisons for O stars 
856 4 0 |u https://doi.org/10.1051/0004-6361/202452241  |x Verlag  |x Resolving-System  |z kostenfrei  |3 Volltext 
856 4 0 |u https://www.aanda.org/articles/aa/abs/2025/02/aa52241-24/aa52241-24.html  |x Verlag  |z kostenfrei  |3 Volltext 
951 |a AR 
992 |a 20250804 
993 |a Article 
994 |a 2025 
998 |g 1294988026  |a Lefever, Roel  |m 1294988026:Lefever, Roel  |d 700000  |d 714000  |d 714100  |e 700000PL1294988026  |e 714000PL1294988026  |e 714100PL1294988026  |k 0/700000/  |k 1/700000/714000/  |k 2/700000/714000/714100/  |p 7 
998 |g 1342551281  |a Josiek, Joris  |m 1342551281:Josiek, Joris  |d 700000  |d 714000  |d 714100  |e 700000PJ1342551281  |e 714000PJ1342551281  |e 714100PJ1342551281  |k 0/700000/  |k 1/700000/714000/  |k 2/700000/714000/714100/  |p 6 
998 |g 1083288482  |a Sander, Andreas A. C.  |m 1083288482:Sander, Andreas A. C.  |d 700000  |d 714000  |d 714100  |e 700000PS1083288482  |e 714000PS1083288482  |e 714100PS1083288482  |k 0/700000/  |k 1/700000/714000/  |k 2/700000/714000/714100/  |p 2 
998 |g 1338011979  |a González i Torà, Gemma  |m 1338011979:González i Torà, Gemma  |d 700000  |d 714000  |d 714100  |e 700000PG1338011979  |e 714000PG1338011979  |e 714100PG1338011979  |k 0/700000/  |k 1/700000/714000/  |k 2/700000/714000/714100/  |p 1  |x j 
999 |a KXP-PPN1932407324  |e 4752919451 
BIB |a Y 
SER |a journal 
JSO |a {"relHost":[{"recId":"253390222","physDesc":[{"extent":"Online-Ressource"}],"note":["Gesehen am 21.06.2024","Erscheint 36mal jährlich in 12 Bänden zu je 3 Ausgaben","Fortsetzung der Druck-Ausgabe"],"corporate":[{"display":"European Southern Observatory","role":"isb"}],"titleAlt":[{"title":"Astronomy & astrophysics"},{"title":"a European journal"}],"type":{"bibl":"periodical","media":"Online-Ressource"},"pubHistory":["1.1969 -"],"language":["eng"],"origin":[{"publisherPlace":"Les Ulis ; Berlin ; Heidelberg","dateIssuedKey":"1969","publisher":"EDP Sciences ; Springer","dateIssuedDisp":"1969-"}],"id":{"zdb":["1458466-9"],"eki":["253390222"],"issn":["1432-0746"]},"part":{"year":"2025","text":"694(2025) vom: Feb., Artikel-ID A269, Seite 1-19","extent":"19","pages":"1-19","volume":"694"},"title":[{"subtitle":"an international weekly journal","title_sort":"Astronomy and astrophysics","title":"Astronomy and astrophysics"}],"disp":"Improving 1D stellar atmosphere models with insights from multi-dimensional simulations I. 1D versus 2D stratifications and spectral comparisons for O starsAstronomy and astrophysics","name":{"displayForm":["European Southern Observatory (ESO)"]}}],"physDesc":[{"noteIll":"Diagramme","extent":"19 S."}],"recId":"1932407324","language":["eng"],"note":["Gesehen am 04.08.2024"],"person":[{"given":"Gemma","display":"González i Torà, Gemma","role":"aut","family":"González i Torà"},{"display":"Sander, Andreas A. C.","role":"aut","family":"Sander","given":"Andreas A. C."},{"given":"Jon","family":"Sundqvist","display":"Sundqvist, Jon","role":"aut"},{"given":"D.","family":"Debnath","role":"aut","display":"Debnath, D."},{"given":"L.","role":"aut","display":"Delbroek, L.","family":"Delbroek"},{"family":"Josiek","role":"aut","display":"Josiek, Joris","given":"Joris"},{"given":"Roel","family":"Lefever","display":"Lefever, Roel","role":"aut"},{"family":"Moens","display":"Moens, N.","role":"aut","given":"N."},{"family":"Sijpt","role":"aut","display":"Sijpt, C. Van der","given":"C. Van der"},{"family":"Verhamme","display":"Verhamme, Olivier","role":"aut","given":"Olivier"}],"id":{"doi":["10.1051/0004-6361/202452241"],"eki":["1932407324"]},"origin":[{"dateIssuedKey":"2025","dateIssuedDisp":"February 2025"}],"name":{"displayForm":["G. González-Torà, A.A.C. Sander, J.O. Sundqvist, D. Debnath, L. Delbroek, J. Josiek, R.R. Lefever, N. Moens, C. Van der Sijpt, and O. Verhamme"]},"title":[{"title_sort":"Improving 1D stellar atmosphere models with insights from multi-dimensional simulations","title":"Improving 1D stellar atmosphere models with insights from multi-dimensional simulations","subtitle":"I. 1D versus 2D stratifications and spectral comparisons for O stars"}],"type":{"media":"Online-Ressource","bibl":"article-journal"}} 
SRT |a GONZALEZITIMPROVING12025