2023A&A...671A..27A


Query : 2023A&A...671A..27A

2023A&A...671A..27A - Astronomy and Astrophysics, volume 671A, 27 (2023/3-1)

Infrared He I 10830 Å, ultra-violet Ca II, and Mg II chromosphere emissions in the spectra of classical Cepheid X Cyg.

ANDRIEVSKY S.M., KOVTYUKH V.V. and KOROTIN S.A.

Abstract (from CDS):

Aims. In a previous publication, we reported the first detection of emission in the infrared (IR) triplet at 10 830 Å in the spectra of the classical Cepheid X Cyg. Emission is detectable at phases from approximately 0.25 to 0.90. We present and discuss further information on the chromosphere activity of this star, namely International Ultraviolet Explorer (IUE) archive data concerning the emission in the h and k Mg II doublet, and near-ultraviolet (NUV) spectra in the vicinity of the H and K Ca II doublet. We also present rough estimates of the chromosphere conditions and semi-empirical modelling of the observed emissions in He I triplet.
Methods. A study of the emissions in UV lines of Ca II and Mg II, and IR lines of He I suggests that the emissions observed at certain phases can be explained within the framework of the Gillet's phenomenological model of shock waves in pulsating atmospheres, which was developed from a study of the Hα behaviour in X Cyg spectra. We used the non-local thermodynamic equilibrium (NLTE) approximation and a simple model of this star's chromosphere for the analysis of the chromosphere indicator profiles.
Results. We show that under certain assumptions about the properties of the chromosphere, it is possible to describe the presence or absence of emission in the IR lines of He I and Ca II, and UV lines of Ca II and Mg II.

Abstract Copyright: © The Authors 2023

Journal keyword(s): stars: atmospheres - stars: chromospheres - stars: variables: Cepheids

Simbad objects: 19

goto Full paper

goto View the references in ADS

Number of rows : 19
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2024
#notes
1 * bet Cas dS* 00 09 10.68518 +59 08 59.2120 2.73 2.61 2.27 1.97 1.77 F2III 531 0
2 * alf UMi cC* 02 31 49.09456 +89 15 50.7923 3.00 2.62 2.02 1.53 1.22 F8Ib 673 2
3 V* SU Cas cC* 02 51 58.7511911208 +68 53 18.606894036 6.92 6.44 5.80     F5.5III+ 424 1
4 V* X Ari RR* 03 08 30.8846437148 +10 26 45.218712967 9.45 9.25 8.97     F0.5 292 0
5 * bet Dor cC* 05 33 37.5159729864 -62 29 23.376457680 5.13 4.58 3.76 3.55 3.12 F8/G0Ib 377 0
6 * 48 Aur cC* 06 28 34.0881845487 +30 29 34.929596860 6.73 6.23 5.55   4.777 F5.5-G0Ib 382 0
7 * zet Gem cC* 07 04 06.5312384690 +20 34 13.074474962 5.20 4.58 3.79   3.082 G1Ib 569 0
8 * rho Pup dS* 08 07 32.6488235 -24 18 15.567946 3.43 3.24 2.81 2.46 2.25 F5IIkF2IImF5II 303 0
9 * l Car cC* 09 45 14.8117044917 -62 30 28.450312664   5.09 3.75     G5Iab/b 318 0
10 V* W Vir WV* 13 26 01.9928807928 -03 22 43.431062880   10.33 9.46 9.29 9.393 F2Ibe 301 0
11 V* AL Vir WV* 14 11 09.0461976912 -13 18 38.439874440   10.13 9.10     F3/5III 86 0
12 V* X Sgr cC* 17 47 33.6239490288 -27 49 50.835778896 5.84 5.34 4.54 6.03 3.661 F7II 333 0
13 V* RR Lyr RR* 19 25 27.9129605304 +42 47 03.693258204   7.36   7.6   kA3hF0 926 0
14 * eta Aql cC* 19 52 28.3689223781 +01 00 20.371980515 5.12 4.61 3.80   3.030 F6Iab+B9.8V 672 0
15 V* X Cyg cC* 20 43 24.1917118680 +35 35 16.077149700 8.69 7.70 6.47   5.241 F7Ib 470 0
16 * tau Cyg dS* 21 14 47.49252 +38 02 43.1441 4.140 4.120 3.730 3.38 3.14 F2IV 282 0
17 * bet Cep bC* 21 28 39.5968513 +70 33 38.574681 2.05 3.01 3.23 3.33 3.55 B0.5IIIs 725 0
18 * rho Cyg PM* 21 33 58.8530450102 +45 35 30.620055459 5.47 4.91 4.02 3.31 2.81 G8IIIFe-0.5 199 0
19 * del Cep cC* 22 29 10.2626640314 +58 24 54.697613650 4.71 4.35 3.75   3.219 F5Iab:+B7-8 730 0

To bookmark this query, right click on this link: simbad:objects in 2023A&A...671A..27A and select 'bookmark this link' or equivalent in the popup menu