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{Hill:2018:mnras/sty2510,
author = {Hill, R and Shariff, H and Trotta, R and Ali-Khan, S and Jiao, X and Liu, Y and Moon, SK and Parker, W and Paulus, M and van, Dyk D and Lucy, LB},
doi = {mnras/sty2510},
journal = {Monthly Notices of the Royal Astronomical Society},
pages = {2766--2777},
title = {Projected distances to host galaxy reduce SNIa dispersion},
url = {http://dx.doi.org/10.1093/mnras/sty2510},
volume = {481},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We use multi-band imagery data from the Sloan Digital Sky Survey (SDSS) to measure projected distances of 302 supernova type Ia (SNIa) from the centre of their host galaxies, normalized to the galaxy's brightness scale length, with a Bayesian approach. We test the hypothesis that SNIas further away from the centre of their host galaxy are less subject to dust contamination (as the dust column density in their environment is maller) and/or come from a more homogeneous environment. Using the Mann-Whitney U test, we find a statistically significant difference in the observed colour correction distribution between SNIas that are near and those that are far from the centre of their host. The local p-value is 3 x 10^{-3}, which is significant at the 5 per cent level after look-elsewhere effect correction. We estimate the residual scatter of thetwo subgroups to be 0.073 +/- 0.018 for the far SNIas, compared to 0.114 +/-0.009 for the near SNIas -- an improvement of 30 per cent, albeit with a low statistical significance of 2sigma. This confirms the importance of host galaxy properties in correctly interpreting SNIa observations for cosmological inference.
AU  - Hill,R
AU  - Shariff,H
AU  - Trotta,R
AU  - Ali-Khan,S
AU  - Jiao,X
AU  - Liu,Y
AU  - Moon,SK
AU  - Parker,W
AU  - Paulus,M
AU  - van,Dyk D
AU  - Lucy,LB
DO  - mnras/sty2510
EP  - 2777
PY  - 2018///
SN  - 0035-8711
SP  - 2766
TI  - Projected distances to host galaxy reduce SNIa dispersion
T2  - Monthly Notices of the Royal Astronomical Society
UR  - http://dx.doi.org/10.1093/mnras/sty2510
UR  - http://hdl.handle.net/10044/1/63101
VL  - 481
ER  -
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