Imperial College London
Portrait Picture

Professor David van Dyk

Faculty of Natural Sciences, Department of Mathematics

Chair in Statistics
 
 
 
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Contact

 

+44 (0)20 7594 8574d.van-dyk Website

 
 
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Assistant

 

Mr David Whittaker +44 (0)20 7594 8481

 
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Location

 

539Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Wagner-Kaiser:2016:mnras/stw2247,
author = {Wagner-Kaiser, R and Stenning, D and Sarajedini, A and von, Hippel T and van, Dyk D and Robinson, E and Stein, NM and Jefferys, W},
doi = {mnras/stw2247},
journal = {Monthly Notices of the Royal Astronomical Society},
pages = {3768--3782},
title = {Bayesian analysis of two stellar populations in Galactic globular clusters III: Analysis of 30 clusters},
url = {http://dx.doi.org/10.1093/mnras/stw2247},
volume = {463},
year = {2016}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We use Cycle 21 Hubble Space Telescope (HST) observations and HST archival ACSTreasury observations of 30 Galactic Globular Clusters to characterize two distinctstellar populations. A sophisticated Bayesian technique is employed to simultaneouslysample the joint posterior distribution of age, distance, and extinction for each cluster,as well as unique helium values for two populations within each cluster and therelative proportion of those populations. We find the helium differences among thetwo populations in the clusters fall in the range of ∼0.04 to 0.11. Because adequatemodels varying in CNO are not presently available, we view these spreads as upperlimits and present them with statistical rather than observational uncertainties. Evidencesupports previous studies suggesting an increase in helium content concurrentwith increasing mass of the cluster and also find that the proportion of the first populationof stars increases with mass as well. Our results are examined in the context ofproposed globular cluster formation scenarios. Additionally, we leverage our Bayesiantechnique to shed light on inconsistencies between the theoretical models and theobserved data.
AU  - Wagner-Kaiser,R
AU  - Stenning,D
AU  - Sarajedini,A
AU  - von,Hippel T
AU  - van,Dyk D
AU  - Robinson,E
AU  - Stein,NM
AU  - Jefferys,W
DO  - mnras/stw2247
EP  - 3782
PY  - 2016///
SN  - 1365-2966
SP  - 3768
TI  - Bayesian analysis of two stellar populations in Galactic globular clusters III: Analysis of 30 clusters
T2  - Monthly Notices of the Royal Astronomical Society
UR  - http://dx.doi.org/10.1093/mnras/stw2247
UR  - http://hdl.handle.net/10044/1/39891
VL  - 463
ER  -
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