An investigation of the formation and line properties of MgH in 3D hydrodynamical model stellar atmospheres

Studies of the isotopic composition of magnesium in cool stars have so far relied upon the use of one-dimensional (1D) model atmospheres. Since the isotopic ratios derived are based on asymmetries of optical MgH lines, it is important to test the impact from other effects affecting line asymmetries,...

Full description

Saved in:
Bibliographic Details
Main Authors: Thygesen, Anders (Author) , Ludwig, Hans-Günter (Author) , Caffau, Elisabetta (Author) , Sbordone, Luca (Author)
Format: Article (Journal) Chapter/Article
Language:English
Published: 2017
In: Arxiv

Online Access:Verlag, kostenfrei, Volltext: http://arxiv.org/abs/1706.04218
Get full text
Author Notes:Anders O. Thygesen, Evan N. Kirby, Andrew J. Gallagher, Hans-G. Ludwig, Elisabetta Caffau, Piercarlo Bonifacio, and Luca Sbordone

MARC

LEADER 00000caa a2200000 c 4500
001 1564279553
003 DE-627
005 20220814001259.0
007 cr uuu---uuuuu
008 171011s2017 xx |||||o 00| ||eng c
035 |a (DE-627)1564279553 
035 |a (DE-576)494279559 
035 |a (DE-599)BSZ494279559 
035 |a (OCoLC)1340980412 
040 |a DE-627  |b ger  |c DE-627  |e rda 
041 |a eng 
084 |a 29  |2 sdnb 
100 1 |a Thygesen, Anders  |e VerfasserIn  |0 (DE-588)105786143X  |0 (DE-627)795342098  |0 (DE-576)413013901  |4 aut 
245 1 3 |a An investigation of the formation and line properties of MgH in 3D hydrodynamical model stellar atmospheres  |c Anders O. Thygesen, Evan N. Kirby, Andrew J. Gallagher, Hans-G. Ludwig, Elisabetta Caffau, Piercarlo Bonifacio, and Luca Sbordone 
264 1 |c 2017 
300 |a 20 
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 11.10.2017 
520 |a Studies of the isotopic composition of magnesium in cool stars have so far relied upon the use of one-dimensional (1D) model atmospheres. Since the isotopic ratios derived are based on asymmetries of optical MgH lines, it is important to test the impact from other effects affecting line asymmetries, like stellar convection. Here, we present a theoretical investigation of the effects of including self-consistent modeling of convection. Using spectral syntheses based on 3D hydrodynamical CO$^5$BOLD models of dwarfs (4000K$\lesssim T_\mathrm{eff}\lesssim5160K$, $4.0\leq$log(g)$\leq4.5$, $-3.0\leq[\mathrm{Fe/H}]\leq-1.0$) and giants ($T_\mathrm{eff}\sim4000$K, log(g)$=1.5$, $-3.0\leq[\mathrm{Fe/H}]\leq-1.0$), we perform a detailed analysis comparing 3D and 1D syntheses. We describe the impact on the formation and behavior of MgH lines from using 3D models, and perform a qualitative assessment of the systematics introduced by the use of 1D syntheses. Using 3D model atmospheres significantly affect the strength of the MgH lines, especially in dwarfs, with 1D syntheses requiring an abundance correction of up to +0.69 dex largest for our 5000K models. The corrections are correlated with $T_\mathrm{eff}$ and are also affected by the metallicity. The shape of the strong $^{24}$MgH component in the 3D syntheses is poorly reproduced in 1D. This results in 1D syntheses underestimating $^{25}$MgH by up to $\sim5$ percentage points and overestimating $^{24}$MgH by a similar amount for dwarfs. This discrepancy increases with decreasing metallicity. $^{26}$MgH is recovered relatively well, with the largest difference being $\sim2$ percentage points. The use of 3D for giants has less impact, due to smaller differences in the atmospheric structure and a better reproduction of the line shape in 1D. 
650 4 |a Astrophysics - Solar and Stellar Astrophysics 
700 1 |a Ludwig, Hans-Günter  |d 1962-  |e VerfasserIn  |0 (DE-588)120980568  |0 (DE-627)705135152  |0 (DE-576)292479476  |4 aut 
700 1 |a Caffau, Elisabetta  |e VerfasserIn  |0 (DE-588)1034792121  |0 (DE-627)747796289  |0 (DE-576)382426363  |4 aut 
700 1 |a Sbordone, Luca  |e VerfasserIn  |0 (DE-588)1034485768  |0 (DE-627)745632955  |0 (DE-576)382088247  |4 aut 
773 0 8 |i Enthalten in  |t Arxiv  |d Ithaca, NY : Cornell University, 1991  |g (2017) Artikel-Nummer 1706.04218, 20 Seiten  |h Online-Ressource  |w (DE-627)509006531  |w (DE-600)2225896-6  |w (DE-576)28130436X  |7 nnas  |a An investigation of the formation and line properties of MgH in 3D hydrodynamical model stellar atmospheres 
773 1 8 |g year:2017  |g extent:20  |a An investigation of the formation and line properties of MgH in 3D hydrodynamical model stellar atmospheres 
856 4 0 |u http://arxiv.org/abs/1706.04218  |x Verlag  |z kostenfrei  |3 Volltext 
951 |a AR 
992 |a 20171011 
993 |a Article 
998 |g 1034485768  |a Sbordone, Luca  |m 1034485768:Sbordone, Luca  |p 7  |y j 
998 |g 1034792121  |a Caffau, Elisabetta  |m 1034792121:Caffau, Elisabetta  |p 5 
998 |g 120980568  |a Ludwig, Hans-Günter  |m 120980568:Ludwig, Hans-Günter  |d 700000  |d 714000  |d 714300  |e 700000PL120980568  |e 714000PL120980568  |e 714300PL120980568  |k 0/700000/  |k 1/700000/714000/  |k 2/700000/714000/714300/  |p 4 
999 |a KXP-PPN1564279553  |e 298381761X 
BIB |a Y 
JSO |a {"title":[{"title_sort":"investigation of the formation and line properties of MgH in 3D hydrodynamical model stellar atmospheres","title":"An investigation of the formation and line properties of MgH in 3D hydrodynamical model stellar atmospheres"}],"physDesc":[{"extent":"20 S."}],"relHost":[{"origin":[{"publisher":"Cornell University ; Arxiv.org","dateIssuedKey":"1991","publisherPlace":"Ithaca, NY ; [Erscheinungsort nicht ermittelbar]","dateIssuedDisp":"1991-"}],"disp":"An investigation of the formation and line properties of MgH in 3D hydrodynamical model stellar atmospheresArxiv","type":{"bibl":"edited-book","media":"Online-Ressource"},"recId":"509006531","id":{"zdb":["2225896-6"],"eki":["509006531"]},"language":["eng"],"note":["Gesehen am 28.05.2024"],"pubHistory":["1991 -"],"titleAlt":[{"title":"Arxiv.org"},{"title":"Arxiv.org e-print archive"},{"title":"Arxiv e-print archive"},{"title":"De.arxiv.org"}],"part":{"text":"(2017) Artikel-Nummer 1706.04218, 20 Seiten","year":"2017","extent":"20"},"title":[{"title_sort":"Arxiv","title":"Arxiv"}],"physDesc":[{"extent":"Online-Ressource"}]}],"name":{"displayForm":["Anders O. Thygesen, Evan N. Kirby, Andrew J. Gallagher, Hans-G. Ludwig, Elisabetta Caffau, Piercarlo Bonifacio, and Luca Sbordone"]},"origin":[{"dateIssuedDisp":"2017","dateIssuedKey":"2017"}],"type":{"media":"Online-Ressource","bibl":"chapter"},"id":{"eki":["1564279553"]},"recId":"1564279553","person":[{"given":"Anders","role":"aut","family":"Thygesen","display":"Thygesen, Anders"},{"given":"Hans-Günter","display":"Ludwig, Hans-Günter","role":"aut","family":"Ludwig"},{"given":"Elisabetta","role":"aut","family":"Caffau","display":"Caffau, Elisabetta"},{"given":"Luca","role":"aut","family":"Sbordone","display":"Sbordone, Luca"}],"language":["eng"],"note":["Gesehen am 11.10.2017"]} 
SRT |a THYGESENANINVESTIGAT2017