2007A&A...461L..13R


C.D.S. - SIMBAD4 rel 1.7 - 2019.09.16CEST23:26:54

2007A&A...461L..13R - Astronomy and Astrophysics, volume 461, L13-16 (2007/1-1)

The extra-mixing efficiency in very low metallicity RGB stars.

RECIO-BLANCO A. and DE LAVERNY P.

Abstract (from CDS):

After the first dredge-up, low-mass Red Giant Branch (RGB) stars experience an extra-mixing episode that strongly affects the chemical abundances on their surface. This mixing occurs at the bump in the luminosity function. In this Letter we describe the efficiency of the extra-mixing in RGB stars found in very metal-poor globular clusters (GC). The VLT/ISAAC spectra of twenty stars located between the bump and the tip of the RGB in four GCs with metallicities between [Fe/H]=-1.2 and -2.5dex were collected. The carbon isotopic ratios on their surface were derived from the second overtone (Δv=2) bands of the CO molecule at 2.3µm with the spectral synthesis method. It is found that the carbon isotopic ratios of very metal-poor GC stars always reach the equilibrium value of the CNO cycle almost immediately above the bump in the luminosity function. No additional mixing episode at brighter luminosities and no variations with the clusters' metallicity were detected. The extra-mixing is therefore found to be very efficient in metal-poor low-mass RGB stars, in very good agreement with theoretical expectations.

Abstract Copyright:

Journal keyword(s): stars: abundances - stars: evolution - stars: late-type - globular clusters: individuals: general

Nomenclature: Table 1: Cl* NGC 6121 RBDL NNN N=7 among (Nos 53-456), Cl* NGC 6397 RBDL NNNN N=5 among (Nos 110-1114), Cl* NGC 7099 RBDL NNNN N=5 among (Nos 3711-7917), Cl* NGC 7078 RBDL NNNN N=3 among (Nos 58-1662).

Simbad objects: 27

goto Full paper

goto View the reference in ADS

Number of rows : 27

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2019
#notes
1 * alf Boo RG* 14 15 39.67207 +19 10 56.6730 2.46 1.18 -0.05 -1.03 -1.68 K1.5IIIFe-0.5 2085 0
2 M 4 GlC 16 23 35.22 -26 31 32.7           ~ 1626 0
3 Cl* NGC 6121 SAW V60 RG* 16 23 45.2125344184 -26 33 56.903140476 15.54 14.82 13.56 12.79 12.02 ~ 17 0
4 Cl* NGC 6121 LEE 4511 *iC 16 23 49.8049106820 -26 33 58.873948795   13.131 11.62     ~ 23 0
5 NGC 6397 GlC 17 40 42.09 -53 40 27.6   7.39 5.17     ~ 1747 1
6 M 15 GlC 21 29 58.33 +12 10 01.2   3       ~ 2832 0
7 M 30 GlC 21 40 22.12 -23 10 47.5     7.10     ~ 877 0
8 Cl* NGC 7099 RBDL 7927 *iC ~ ~     13.2     ~ 1 0
9 Cl* NGC 6397 RBDL 1114 *iC ~ ~     9.9     ~ 1 0
10 Cl* NGC 6397 RBDL 429 *iC ~ ~     11.5     ~ 1 0
11 Cl* NGC 6397 RBDL 224 *iC ~ ~     10.7     ~ 1 0
12 Cl* NGC 7099 RBDL 3711 *iC ~ ~     13.0     ~ 1 0
13 Cl* NGC 6121 RBDL 456 *iC ~ ~     13.5     ~ 1 0
14 Cl* NGC 7099 RBDL 7917 *iC ~ ~     12.1     ~ 1 0
15 Cl* NGC 7078 RBDL 665 *iC ~ ~     13.5     ~ 1 0
16 Cl* NGC 7078 RBDL 1662 *iC ~ ~     12.8     ~ 1 0
17 Cl* NGC 6121 RBDL 53 *iC ~ ~     13.5     ~ 1 0
18 Cl* NGC 6121 RBDL 113 *iC ~ ~     12.5     ~ 1 0
19 Cl* NGC 6397 RBDL 110 *iC ~ ~     11.5     ~ 1 0
20 Cl* NGC 6121 RBDL 152 *iC ~ ~     13.7     ~ 1 0
21 Cl* NGC 7099 RBDL 3998 *iC ~ ~     12.1     ~ 1 0
22 Cl* NGC 6121 RBDL 213 *iC ~ ~     12.9     ~ 1 0
23 Cl* NGC 6121 RBDL 148 *iC ~ ~     13.4     ~ 1 0
24 Cl* NGC 7078 RBDL 58 *iC ~ ~     13.3     ~ 1 0
25 Cl* NGC 6397 RBDL 183 *iC ~ ~     11.8     ~ 1 0
26 Cl* NGC 6121 RBDL 304 *iC ~ ~     11.5     ~ 1 0
27 Cl* NGC 7099 RBDL 7640 *iC ~ ~     12.6     ~ 1 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2007A&A...461L..13R and select 'bookmark this link' or equivalent in the popup menu


2019.09.16-23:26:54

© Université de Strasbourg/CNRS

    • Contact