2014A&A...567A.105F


C.D.S. - SIMBAD4 rel 1.7 - 2020.07.10CEST01:34:30

2014A&A...567A.105F - Astronomy and Astrophysics, volume 567A, 105-105 (2014/7-1)

The colour-magnitude relation of globular clusters in Centaurus and Hydra. Constraints on star cluster self-enrichment with a link to massive Milky Way globular clusters.

FENSCH J., MIESKE S., MUELLER-SEIDLITZ J. and HILKER M.

Abstract (from CDS):

We investigate the colour-magnitude relation of metal-poor globular clusters, the so-called blue tilt, in the Hydra and Centaurus galaxy clusters and constrain the primordial conditions for star cluster self-enrichment. We analyse U,I photometry for about 2500 globular clusters in the central regions of Hydra and Centaurus, based on VLT/FORS1 data. We measure the relation between mean colour and luminosity for the blue and red subpopulation of the globular cluster samples. We convert these relations into mass-metallicity space and compare the obtained GC mass-metallicity relation with predictions from the star cluster self-enrichment model by Bailin & Harris (2009ApJ...695.1082B). For this we include effects of dynamical and stellar evolution and a physically well motivated primordial mass-radius scaling. We obtain a mass-metallicity scaling of Z∝M0.27±0.05 for Centaurus GCs and Z ∝M0.40±0.06 for Hydra GCs, consistent with the range of observed relations in other environments. We find that the GC mass-metallicity relation already sets in at present-day masses of a few 105M and is well established in the luminosity range of massive MW clusters like ω Centauri. The inclusion of a primordial mass-radius scaling of star clusters significantly improves the fit of the self-enrichment model to the data. The self-enrichment model accurately reproduces the observed relations for average primordial half-light radii rh∼1-1.5pc, star formation efficiencies f*∼0.3-0.4, and pre-enrichment levels of [Fe/H] -1.7 dex. The slightly steeper blue tilt for Hydra can be explained either by a ∼30% smaller average rh at fixed f*∼0.3, or analogously by a ∼20% smaller f* at fixed rh∼1.5pc. Within the self-enrichment scenario, the observed blue tilt implies a correlation between GC mass and width of the stellar metallicity distribution. We find that this implied correlation matches the trend of width with GC mass measured in Galactic GCs, including extreme cases like ω Centauri and M54. First, we found that a primordial star cluster mass-radius relation provides a significant improvement to the self-enrichment model fits. Second we show that broadened metallicity distributions as found in some massive MW globular clusters may have arisen naturally from self-enrichment processes, without the need of a dwarf galaxy progenitor.

Abstract Copyright:

Journal keyword(s): supernovae: general - globular clusters: general - galaxies: star clusters: general - stars: formation

Simbad objects: 14

goto Full paper

goto View the reference in ADS

Number of rows : 14

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 M 31 G 00 42 44.330 +41 16 07.50 4.86 4.36 3.44     ~ 10904 1
2 NGC 1399 BiC 03 38 29.083 -35 27 02.67 11.05 9.74 9.59 8.12   ~ 1449 1
3 ACO S 373 ClG 03 38 30 -35 27.3           ~ 1538 0
4 NAME HYA SUPERCL SCG 08 57.9 +03 10           ~ 152 0
5 NGC 3309 GiG 10 36 35.651 -27 31 06.35   11.98 11.78 10.34 10.51 ~ 144 0
6 NAME Hydra I Cluster ClG 10 36 36.0 -27 31 04           ~ 774 1
7 NGC 3311 BiC 10 36 42.821 -27 31 42.02   11.93 10.93 10.00 9.67 ~ 269 2
8 NAME Vir I ClG 12 26 32.1 +12 43 24   10.00 8.49     ~ 5825 0
9 M 104 LIN 12 39 59.43185 -11 37 22.9954 9.51 9.55 8.00 8.05   ~ 1275 3
10 NGC 4696 BiC 12 48 49.277 -41 18 39.92   11.21   10.7   ~ 455 3
11 ACO 3526 ClG 12 48 51.8 -41 18 21           ~ 971 2
12 NGC 4709 GiG 12 50 03.948 -41 22 55.46   12.48 11.32 10.89   ~ 118 0
13 NGC 5139 GlC 13 26 47.28 -47 28 46.1   6.12 5.33     ~ 2997 0
14 M 54 GlC 18 55 03.33 -30 28 47.5           ~ 898 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2014A&A...567A.105F and select 'bookmark this link' or equivalent in the popup menu


2020.07.10-01:34:30

© Université de Strasbourg/CNRS

    • Contact