CDS

2004A&A...417..235E

Query : 2004A&A...417..235E

2004A&A...417..235E - Astronomy and Astrophysics, volume 417, 235-246 (2004/4-1)

Analysis of α Centauri AB including seismic constraints.

EGGENBERGER P., CHARBONNEL C., TALON S., MEYNET G., MAEDER A., CARRIER F. and BOURBAN G.

Abstract (from CDS):

Detailed models of α Cen A and B based on new seismological data for α Cen B by Carrier & Bourban (2003A&A...406L..23C) have been computed using the Geneva evolution code including atomic diffusion. Taking into account the numerous observational constraints now available for the α Cen system, we find a stellar model which is in good agreement with the astrometric, photometric, spectroscopic and asteroseismic data. The global parameters of the α Cen system are now firmly constrained to an age of t=6.52±0.30Gyr, an initial helium mass fraction Yi=0.275±0.010 and an initial metallicity (Z/X)i=0.0434±0.0020. Thanks to these numerous observational constraints, we confirm that the mixing-length parameter α of the B component is larger than the one of the A component, as already suggested by many authors (Noels et al., 1991A&A...247..247N; Fernandes & Neuforge, 1995A&A...295..678F; Guenther & Demarque, 2000ApJ...531..503G): αB is about 8% larger than αA (αA=1.83±0.10 and αB=1.97±0.10). Moreover, we show that asteroseismic measurements enable to determine the radii of both stars with a very high precision (errors smaller than 0.3%). The radii deduced from seismological data are compatible with the new interferometric results of Kervella et al. (2003A&A...404.1087K) even if they are slightly larger than the interferometric radii (differences smaller than 1%).

Abstract Copyright: ∼

Journal keyword(s): stars: binaries: visual - stars: individual: α Cen - stars: evolution - stars: oscillations

Simbad objects: 1

goto Full paper

goto View the references in ADS

Number of rows : 1
N Identifier Otype ICRS (J2000)
RA 		ICRS (J2000)
DEC 		Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023 		#notes
1 * alf Cen ** 14 39 29.71993 -60 49 55.9990   0.4 -0.1     G2V+K1V 930 0

Query : 2004A&A...417..235E

Basic data :
* alf Cen -- Double or Multiple Star
Origin of the objects types :

(Ref) Object type as listed in the reference "Ref"
(acronym) Object type linked to the acronym according to the original reference
() Anterior to 2007, before we can link the objet type to a reference, or given by the CDS team in some particular cases

Other object types: 		* (*,CD,...), X (1E,2E,...), ** (CCDM,**,...), UV (2EUVE,EUVE,...), PM* (Ci,PM), SB* (SBC7), IR (IRAS)
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
  • ra dec : right ascension and declination (unit and frame defined according to your Output Options)
    Grey values are increasing the original precision due to the computation of frame transformations
  • (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
  • [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
    position angle (in degrees North celestial pole to East)
  • quality : flag of quality
    • E ≥ 10"
    • D : 1-10" (and some old data)
    • C : 0.1-1"
    • B : 0.01-0.1" + 2MASS, Tyc
    • A : VLBI, Hipparcos
  • bibcode : bibcode of the coordinates reference
ICRS coord. (ep=J2000) : 		14 39 29.71993 -60 49 55.9990 (Optical) [ ] C 2016A&A...589A.115S
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
  • ra dec : right ascension and declination (unit and frame defined according to your Output Options)
    Grey values are increasing the original precision due to the computation of frame transformations
  • (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
  • [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
    position angle (in degrees North celestial pole to East)
  • quality : flag of quality
    • E ≥ 10"
    • D : 1-10" (and some old data)
    • C : 0.1-1"
    • B : 0.01-0.1" + 2MASS, Tyc
    • A : VLBI, Hipparcos
  • bibcode : bibcode of the coordinates reference
FK4 coord. (ep=B1950 eq=1950) : 		14 36 04.76507 -60 37 36.4825 [ ]
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
  • ra dec : right ascension and declination (unit and frame defined according to your Output Options)
    Grey values are increasing the original precision due to the computation of frame transformations
  • (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
  • [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
    position angle (in degrees North celestial pole to East)
  • quality : flag of quality
    • E ≥ 10"
    • D : 1-10" (and some old data)
    • C : 0.1-1"
    • B : 0.01-0.1" + 2MASS, Tyc
    • A : VLBI, Hipparcos
  • bibcode : bibcode of the coordinates reference
Gal coord. (ep=J2000) : 		315.72230639 -00.67247305 [ ]
Syntax of proper motions is : "pm-ra pm-dec [error ellipse] quality bibcode"
  • pm-ra : mu-ra*cos(dec) (expressed in the ICRS system in mas/yr)
  • pm-dec : mu-dec (expressed in the ICRS system in mas/yr)
  • [error ellipse] : error major axis and minor axis (in mas), orientation angle (in deg)
  • quality : flag of quality (A=best quality -> E=worst quality, {� } =unknown quality)
  • bibcode : bibcode of the proper motion reference
Proper motions mas/yr : 		-3608 686 [30 25 179] C ~
Syntax of radial velocity (or/and redshift) is : "value [error] (wavelength) quality bibcode"
  • value : radial velocity or/and redshift (Heliocentric frame) according to your Output Options
    (redshift may be not displayed if the data value is <0 and the database inside value is a radial velocity)
  • [error] : error of the corresponding value displayed before
  • (wavelength) : wavelength range of the measurement : Rad, mm, IR, Opt, UV, Xray, Gam or  '∼'(unknown)
  • quality : flag of quality ( A=best quality -> E=worst quality, {� } =unknown quality)
  • bibcode : bibcode of the value's origin
Radial velocity / Redshift / cz : 		V(km/s) -22.3 [0.9] / z(~) -0.000074 [0.000003] / cz -22.30 [0.90]
   A 1979IAUS...30...57E
Syntax of parallax is : 'value quality [error] bibcode'
  • value : parallax value
  • quality : flag of quality (A=best quality -> E=worst quality, {� } =unknown quality)
  • [error] : mean error
  • bibcode : bibcode of the parallax reference
Parallaxes (mas): 		742 [~] D ~
Spectral type is made of 3 parts: %coding is composed of 4 parts :
  • the spectral type, which is made of a temperature class, eventually a luminosity class (roman number) and/or spectral peculiarities;
  • a quality letter: A=best quality→E=worst quality, {� } =unknown quality %
  • a quality letter: A=best quality -> E=worst quality, {� } =unknown quality
  • bibcode : bibcode of the spectral type reference
Spectral type: 		G2V+K1V C 2006A&A...460..695T
Syntax of fluxes (or magnitudes) is : "filter-name (System) flux-value [error] quality MultVarFlags bibcode"
  • filter-name : U, B, V, R, I, G, J, H, K, u, g, r, i, z
  • (System) : may be AB (default is Vega)
  • flux-value : value of flux or magnitude
  • [error] : error value
  • quality : flag of quality of the flux value ( A=best quality -> E=worst quality, {� } =unknown quality)
  • MultVarFlags : Mult is zero or one char (J) for joined photometry ; Var can be zero or two chars (V[0-4])
  • bibcode : bibcode of the flux reference
Fluxes (2) :
B 0.4 [~] E ~
V -0.1 [~] E ~
SIMBAD within arcmin
', {sourceSize:12, color:'#30a090'})); aladin.on('objectClicked', function(object) { var objName=object.data.MAIN_ID; aladin.showPopup(object.ra,object.dec,'',''+ objName+''); });" title="Show Simbad objects"> Overlay Simbad points in this preview
Back
All CDSPortal (CDSPortal)
Send to sendBySAMP sendBySAMP
sedIcon
within arcsec The VizieR photometry tool allows for easy visualization of photometry points extracted around the Simbad position from photometry-enabled catalogues in VizieR.
The search radius has to be specified by the user. It is currently limited to a maximum of 30 arcsec. It depends mostly on the precision or quality of the coordinates (SIMBAD and VizieR catalogs), the resolution of the images from which the sources were extracted, source extent, and source crowding.
Suggestions are: crowded field: 0.5 to 1.5 arcsec, 3 arcsec otherwise; uncertain coordinates (SIMBAD quality E or coordinates without reference): 5 to 30 arsec (risky!). sed-help-icon

Hierarchy : number of linked objects
whatever the membership probability is (see description here ) :

The count displayed here is the number of children objects.
The list obtained by clicking the button may be larger, as some children may be linked with different references or probability.

%This number is the number of distinct objets linked, by using this button, you will obtain all links (may be more than one) from that object to his children

: 2 		Display criteria :

The link on the acronym of the identifiers give access to the information for this acronym in the dictionary of nomenclature.
Identifiers (36) :
An access of full data is available using the icon Vizier near the identifier of the catalogue

CCDM J14396-6050AB 1E 143555-6037.6 GES J14392972-6049560 RE J143944-605008
* alf Cen 2E 3308 HD 128620J RX J1439.5-6050
** RHD 1 2E 1435.9-6037 IDS 14328-6025 AB 1RXS J143940.4-605020
** LDS 494AB 1ES 1435-60.6 IRAS 14359-6037 SAO 252838
CD-60 5293 2EUVE J1439-60.8 LPM 534 SBC7 520
Ci 20 875 EUVE J1439-60.8 PM 14362-6038 uvby98 100128620
CPD-60 5483 FK5 538 2RE J143941-605000 WDS J14396-6050AB
CSI-60 5483 43 GC 19728 2RE J1439-605 WDS J14403-6051AB
1E 143556-6037.3 GCRV 8519 RE J1439-605 [TSA98] J143948.42-605021.66

References (930 between 1850 and 2023) (Total 930)
Simbad bibliographic survey began in 1850 for stars (at least bright stars) and in 1983 for all other objects (outside the solar system).
Follow new references on this object
                Reference summaries :

                from: to:

                 or select by : (not exhaustive, explanation here)

Collections of Measurements


velocities : 3    Fe_H : 1    PM : 2   

   

Observing logs


ISO : 5    XMM : 7   

   

External archives :

Archive data at HEASARC - High-Energy Astrophysics Science Archive Research Center

Data at NED - NASA/IPAC Extragalactic Database : * alf Cen

Link by name to the catalogue in VizieR :

CCDM J14396-6050AB CD-60 5293 CPD-60 5483 2E 3308 EUVE J1439-60.8
FK5 538 HD 128620J IRAS 14359-6037 2RE J143941-605000 2RE J1439-605
1RXS J143940.4-605020 SAO 252838 uvby98 100128620 WDS J14396-6050AB WDS J14403-6051AB

Search by coordinates in Vizier (radius: 20 arcsec)

Annotations :
Annotations allow a user to add a note or report an error concerning the astronomical object and its data. It requires registration to post a note. See description .
Please, have a look at Best practices. The list of all annotations to SIMBAD objects can be found here .

report an error concerning the data of this object

To bookmark this query, right click on this link: simbad:objects in 2004A&A...417..235E and select 'bookmark this link' or equivalent in the popup menu

2023.06.04-19:15:49

© Université de Strasbourg/CNRS

    • Contact