Spectroscopic properties of a two-dimensional time-dependent Cepheid model: I. Description and validation of the model
Standard spectroscopic analyses of Cepheid variables are based on hydrostatic one-dimensional model atmospheres, with convection treated using various formulations of mixing-length theory.<i>Aims. <i/>This paper aims to carry out an investigation of the validity of the quasi-static appro...
Gespeichert in:
| Hauptverfasser: | , , |
|---|---|
| Dokumenttyp: | Article (Journal) |
| Sprache: | Englisch |
| Veröffentlicht: |
25 October 2017
|
| In: |
Astronomy and astrophysics
Year: 2017, Jahrgang: 606 |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/201731422 |
| Online-Zugang: | Verlag, kostenfrei, Volltext: http://dx.doi.org/10.1051/0004-6361/201731422 Verlag, kostenfrei, Volltext: https://www.aanda.org/articles/aa/abs/2017/10/aa31422-17/aa31422-17.html 
|
| Verfasserangaben: | V. Vasilyev, H.-G. Ludwig, B. Freytag, B. Lemasle, and M. Marconi |
MARC
| LEADER | 00000caa a2200000 c 4500 | ||
|---|---|---|---|
| 001 | 1571413545 | ||
| 003 | DE-627 | ||
| 005 | 20220814101314.0 | ||
| 007 | cr uuu---uuuuu | ||
| 008 | 180326s2017 xx |||||o 00| ||eng c | ||
| 024 | 7 | |a 10.1051/0004-6361/201731422 |2 doi | |
| 035 | |a (DE-627)1571413545 | ||
| 035 | |a (DE-576)501413545 | ||
| 035 | |a (DE-599)BSZ501413545 | ||
| 035 | |a (OCoLC)1340994968 | ||
| 040 | |a DE-627 |b ger |c DE-627 |e rda | ||
| 041 | |a eng | ||
| 084 | |a 29 |2 sdnb | ||
| 100 | 1 | |a Vasilyev, Valeriy |d 1990- |e VerfasserIn |0 (DE-588)1153929236 |0 (DE-627)1015531504 |0 (DE-576)500649480 |4 aut | |
| 245 | 1 | 0 | |a Spectroscopic properties of a two-dimensional time-dependent Cepheid model |b I. Description and validation of the model |c V. Vasilyev, H.-G. Ludwig, B. Freytag, B. Lemasle, and M. Marconi |
| 264 | 1 | |c 25 October 2017 | |
| 300 | |a 13 | ||
| 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 12.01.2021 | ||
| 520 | |a Standard spectroscopic analyses of Cepheid variables are based on hydrostatic one-dimensional model atmospheres, with convection treated using various formulations of mixing-length theory.<i>Aims. <i/>This paper aims to carry out an investigation of the validity of the quasi-static approximation in the context of pulsating stars. We check the adequacy of a two-dimensional time-dependent model of a Cepheid-like variable with focus on its spectroscopic properties. <i>Methods. <i/>With the radiation-hydrodynamics code CO5BOLD, we construct a two-dimensional time-dependent envelope model of a Cepheid with <i>T<i/><sub>eff<sub/> = 5600 K, log <i>g<i/> = 2.0, solar metallicity, and a 2.8-day pulsation period. Subsequently, we perform extensive spectral syntheses of a set of artificial iron lines in local thermodynamic equilibrium. The set of lines allows us to systematically study effects of line strength, ionization stage, and excitation potential.<i>Results. <i/>We evaluate the microturbulent velocity, line asymmetry, projection factor, and Doppler shifts. The microturbulent velocity, averaged over all lines, depends on the pulsational phase and varies between 1.5 and 2.7 km s<sup>-1<sup/>. The derived projection factor lies between 1.23 and 1.27, which agrees with observational results. The mean Doppler shift is non-zero and negative, −1 km s<sup>-1<sup/>, after averaging over several full periods and lines. This residual line-of-sight velocity (related to the “K-term”) is primarily caused by horizontal inhomogeneities, and consequently we interpret it as the familiar convective blueshift ubiquitously present in non-pulsating late-type stars. Limited statistics prevent firm conclusions on the line asymmetries.<i>Conclusions. <i/>Our two-dimensional model provides a reasonably accurate representation of the spectroscopic properties of a short-period Cepheid-like variable star. Some properties are primarily controlled by convective inhomogeneities rather than by the Cepheid-defining pulsations. Extended multi-dimensional modelling offers new insight into the nature of pulsating stars. | ||
| 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 Lemasle, Bertrand |e VerfasserIn |0 (DE-588)1142258106 |0 (DE-627)1001430220 |0 (DE-576)494750596 |4 aut | |
| 773 | 0 | 8 | |i Enthalten in |t Astronomy and astrophysics |d Les Ulis : EDP Sciences, 1969 |g 606(2017) Artikel-Nummer A140, 13 Seiten |h Online-Ressource |w (DE-627)253390222 |w (DE-600)1458466-9 |w (DE-576)072283351 |x 1432-0746 |7 nnas |a Spectroscopic properties of a two-dimensional time-dependent Cepheid model I. Description and validation of the model |
| 773 | 1 | 8 | |g volume:606 |g year:2017 |g extent:13 |a Spectroscopic properties of a two-dimensional time-dependent Cepheid model I. Description and validation of the model |
| 856 | 4 | 0 | |u http://dx.doi.org/10.1051/0004-6361/201731422 |x Verlag |x Resolving-System |z kostenfrei |3 Volltext |
| 856 | 4 | 0 | |u https://www.aanda.org/articles/aa/abs/2017/10/aa31422-17/aa31422-17.html |x Verlag |z kostenfrei |3 Volltext |
| 951 | |a AR | ||
| 992 | |a 20180326 | ||
| 993 | |a Article | ||
| 994 | |a 2017 | ||
| 998 | |g 1142258106 |a Lemasle, Bertrand |m 1142258106:Lemasle, Bertrand |d 500000 |d 500881 |e 500000PL1142258106 |e 500881PL1142258106 |k 0/500000/ |k 1/500000/500881/ |p 4 | ||
| 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 2 | ||
| 998 | |g 1153929236 |a Vasilyev, Valeriy |m 1153929236:Vasilyev, Valeriy |d 130000 |e 130000PV1153929236 |k 0/130000/ |p 1 |x j | ||
| 999 | |a KXP-PPN1571413545 |e 3004268981 | ||
| BIB | |a Y | ||
| SER | |a journal | ||
| JSO | |a {"language":["eng"],"note":["Gesehen am 12.01.2021"],"person":[{"display":"Vasilyev, Valeriy","role":"aut","family":"Vasilyev","given":"Valeriy"},{"family":"Ludwig","role":"aut","display":"Ludwig, Hans-Günter","given":"Hans-Günter"},{"role":"aut","family":"Lemasle","display":"Lemasle, Bertrand","given":"Bertrand"}],"type":{"media":"Online-Ressource","bibl":"article-journal"},"id":{"eki":["1571413545"],"doi":["10.1051/0004-6361/201731422"]},"recId":"1571413545","origin":[{"dateIssuedKey":"2017","dateIssuedDisp":"25 October 2017"}],"name":{"displayForm":["V. Vasilyev, H.-G. Ludwig, B. Freytag, B. Lemasle, and M. Marconi"]},"relHost":[{"physDesc":[{"extent":"Online-Ressource"}],"part":{"year":"2017","text":"606(2017) Artikel-Nummer A140, 13 Seiten","volume":"606","extent":"13"},"language":["eng"],"recId":"253390222","type":{"media":"Online-Ressource","bibl":"periodical"},"name":{"displayForm":["European Southern Observatory (ESO)"]},"title":[{"subtitle":"an international weekly journal","title_sort":"Astronomy and astrophysics","title":"Astronomy and astrophysics"}],"note":["Gesehen am 21.06.2024","Erscheint 36mal jährlich in 12 Bänden zu je 3 Ausgaben","Fortsetzung der Druck-Ausgabe"],"titleAlt":[{"title":"Astronomy & astrophysics"},{"title":"a European journal"}],"pubHistory":["1.1969 -"],"id":{"eki":["253390222"],"zdb":["1458466-9"],"issn":["1432-0746"]},"disp":"Spectroscopic properties of a two-dimensional time-dependent Cepheid model I. Description and validation of the modelAstronomy and astrophysics","corporate":[{"role":"isb","display":"European Southern Observatory"}],"origin":[{"publisherPlace":"Les Ulis ; Berlin ; Heidelberg","dateIssuedKey":"1969","dateIssuedDisp":"1969-","publisher":"EDP Sciences ; Springer"}]}],"title":[{"title":"Spectroscopic properties of a two-dimensional time-dependent Cepheid model","subtitle":"I. Description and validation of the model","title_sort":"Spectroscopic properties of a two-dimensional time-dependent Cepheid model"}],"physDesc":[{"extent":"13 S."}]} | ||
| SRT | |a VASILYEVVASPECTROSCO2520 | ||