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J/A+A/601/A41       Palomar 5 abundance analysis               (Koch+, 2017)

Galactic Pal-eontology: abundance analysis of the disrupting globular cluster Palomar 5. Koch A., Code P. <Astron. Astrophys. 601, A41 (2017)> =2017A&A...601A..41K (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Abundances Keywords: techniques: spectroscopic - stars: abundances - Galaxy: abundances - Galaxy: evolution - Galaxy: halo - globular clusters: individual: Palomar 5 Abstract: We present a chemical abundance analysis of the tidally disrupted globular cluster (GC) Palomar 5. By co-adding high-resolution spectra of 15 member stars from the cluster's main body, taken at low signal-to-noise with the Keck/HIRES spectrograph, we were able to measure integrated abundance ratios of 24 species of 20 elements including all major nucleosynthetic channels (namely the light element Na; α-elements Mg, Si, Ca, Ti; Fe-peak and heavy elements Sc, V, Cr, Mn, Co, Ni, Cu, Zn; and the neutron-capture elements Y, Zr, Ba, La, Nd, Sm, Eu). The mean metallicity of -1.56±0.02±0.06dex (statistical and systematic errors) agrees well with the values from individual, low-resolution measurements of individual stars, but it is lower than previous high-resolution results of a small number of stars in the literature. Comparison with Galactic halo stars and other disrupted and unperturbed GCs renders Pal 5 a typical representative of the Milky Way halo population, as has been noted before, emphasizing that the early chemical evolution of such clusters is decoupled from their later dynamical history. We also performed a test as to the detectability of light element variations in this co-added abundance analysis technique and found that this approach is not sensitive even in the presence of a broad range in sodium of ∼0.6dex, a value typically found in the old halo GCs. Thus, while methods of determining the global abundance patterns of such objects are well suited to study their overall enrichment histories, chemical distinctions of their multiple stellar populations is still best obtained from measurements of individual stars. Description: The Pal 5 data discussed here were taken as part of a broader program to study the internal dynamics of outer halo GCs (see, e.g., Cote et al., 2002ApJ...574..783C; Jordi et al., 2009AJ....137.4586J; Baumgardt et al., 2009MNRAS.396.2051B; Frank et al., 2012, Cat. J/MNRAS/423/2917). Our Pal 5 target stars were chosen from the red giant branch (RGB) and asymptotic giant branch (AGB) sequences identified in the early photometric studies of Sandage & Hartwick (1977AJ.....82..459S, SH77) and the unpublished photometry and astrometry from Cudworth, Schweitzer, and Majewski (CSM; see Schweitzer et al., 1993, in The Globular Cluster-Galaxy Connection, ASP Conf. Ser., 48, 113). Objects: ------------------------------------------------- RA (2000) DE Designation(s) ------------------------------------------------- 15 16 05.30 -00 06 41.0 Palomar 5 = UGC 9792 ------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3.dat 50 258 Line list
See also: J/MNRAS/423/2917 : Radial velocities in Pal 4 (Frank+, 2012) J/ApJ/819/1 : Wide-field photometry of the GC Palomar 5 (Ibata+, 2016) J/ApJ/823/157 : Pal 5 tidal stream LOS velocities + [Fe/H] (Ishigaki+, 2016) Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 5 A5 --- Ion Ion designation 7- 13 F7.2 0.1nm Wave Wavelength 17- 20 F4.2 eV EP Excitation potential 24- 29 F6.3 [-] loggf Oscillator strength 34- 36 I3 10-13m EW255 ?=- Equivalent width for entire sample (1) 40- 43 I4 10-13m EW20 ?=- Equivalent width for RGB subsample (1) 47- 50 I4 10-13m EW9 ?=- Equivalent width for AGB subsample (1)
Note (1): In milli-Angstroms.
Acknowledgements: Andreas Koch, a.koch1(at)lancaster.ac.uk
(End) Patricia Vannier [CDS] 08-Mar-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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