2014MNRAS.440.2953B


C.D.S. - SIMBAD4 rel 1.7 - 2021.05.17CEST03:57:54

2014MNRAS.440.2953B - Mon. Not. R. Astron. Soc., 440, 2953-2968 (2014/June-1)

Validation of optimized population synthesis through mock spectra and Galactic globular clusters.

BARBER C., COURTEAU S., ROEDIGER J.C. and SCHIAVON R.P.

Abstract (from CDS):

Optimized population synthesis provides an empirical method to extract the relative mix of stellar evolutionary stages and the distribution of atmospheric parameters within unresolved stellar systems, yet a robust validation of this method is still lacking. We here provide a calibration of population synthesis via non-linear bound-constrained optimization of stellar populations based upon optical spectra of mock stellar systems and observed Galactic globular clusters (GGCs). The MILES stellar library is used as a basis for mock spectra as well as templates for the synthesis of deep GGC spectra from Schiavon et al. Optimized population synthesis applied to mock spectra recovers mean light-weighted stellar atmospheric parameters within a mean uncertainty of 240 K, 0.04 dex, and 0.03 dex for Teff, logg, and [Fe/H], respectively. We use additional information from Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) deep colour-magnitude diagrams (CMDs) from Sarajedini et al. and literature metallicities to validate our optimization results on GGCs. Decompositions of both mock and GGC spectra confirm the method's ability to recover the expected mean light-weighted metallicity in dust-free conditions (E(B - V) ≲ 0.15) with uncertainties comparable to evolutionary population synthesis methods. Dustier conditions require either appropriate dust modelling when fitting to the full spectrum, or fitting only to select spectral features. We derive light-weighted fractions of stellar evolutionary stages from our population synthesis fits to GGCs, yielding on average a combined 25±6 percent from main-sequence and turn-off dwarfs, 64±7 percent from subgiant, red giant, and asymptotic giant branch stars, and 15±7 percent from horizontal branch stars and blue stragglers. Excellent agreement is found between these fractions and those estimated from deep HST/ACS CMDs. Overall, optimized population synthesis remains a powerful tool for understanding the stellar populations within the integrated light of galaxies and globular clusters.

Abstract Copyright: © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society (2014)

Journal keyword(s): methods: numerical - techniques: spectroscopic - catalogues - Hertzsprung-Russell and colour-magnitude diagrams - globular clusters: general - galaxies: stellar content

Simbad objects: 26

goto Full paper

goto View the reference in ADS

Number of rows : 26

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 NGC 104 GlC 00 24 05.359 -72 04 53.20   5.78 4.09     ~ 3637 0
2 NGC 1851 GlC 05 14 06.76 -40 02 47.6   8.80 7.23     ~ 1279 0
3 M 79 GlC 05 24 10.59 -24 31 27.3   9.21 8.16     ~ 738 0
4 NGC 2298 GlC 06 48 59.41 -36 00 19.1   10.77 8.89     ~ 444 0
5 NGC 2808 GlC 09 12 03.10 -64 51 48.6           ~ 1292 0
6 NGC 3201 GlC 10 17 36.82 -46 24 44.9           ~ 760 0
7 NGC 5286 GlC 13 46 26.81 -51 22 27.3   9.18 8.31     ~ 385 0
8 M 5 GlC 15 18 33.22 +02 04 51.7   7.34 5.95     ~ 1815 0
9 NGC 5927 GlC 15 28 00.69 -50 40 22.9   10.13 8.86     ~ 418 0
10 NGC 5986 GlC 15 46 03.00 -37 47 11.1     6.92     ~ 322 0
11 M 4 GlC 16 23 35.22 -26 31 32.7           ~ 1713 0
12 M 107 GlC 16 32 31.86 -13 03 13.6   9.96 8.85     ~ 727 0
13 M 12 GlC 16 47 14.18 -01 56 54.7   8.52 6.07     ~ 600 0
14 M 10 GlC 16 57 09.05 -04 06 01.1     4.98     ~ 714 0
15 NGC 6304 GlC 17 14 32.25 -29 27 43.3   10.33 9.03     ~ 310 0
16 NGC 6352 GlC 17 25 29.11 -48 25 19.8   9.95 8.87     ~ 353 0
17 NGC 6362 GlC 17 31 54.99 -67 02 54.0   9.72 8.86     ~ 506 0
18 NGC 6388 GlC 17 36 17.461 -44 44 08.34   7.40       ~ 832 1
19 NGC 6441 GlC 17 50 13.06 -37 03 05.2   9.26 8.00     ~ 793 0
20 NGC 6624 GlC 18 23 40.51 -30 21 39.7           ~ 799 1
21 M 69 GlC 18 31 23.10 -32 20 53.1   9.32 8.31     ~ 421 1
22 NGC 6652 GlC 18 35 45.63 -32 59 26.6   10.64 9.75     ~ 366 0
23 NGC 6723 GlC 18 59 33.15 -36 37 56.1           ~ 446 0
24 NGC 6752 GlC 19 10 52.11 -59 59 04.4   6.96 6.28     ~ 1847 0
25 M 71 GlC 19 53 46.49 +18 46 45.1   7.91 6.1     ~ 1045 0
26 M 2 GlC 21 33 27.02 -00 49 23.7     6.25     ~ 928 1

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2014MNRAS.440.2953B and select 'bookmark this link' or equivalent in the popup menu


2021.05.17-03:57:54

© Université de Strasbourg/CNRS

    • Contact