The significance of anisotropic signals hiding in the Type Ia supernovae

doi:http://dx.doi.org/10.1093/mnras/stw995

CORC > 理论物理研究所 > 中国科学院理论物理研究所 > 理论物理所科研产出 > 理论物理所1978-2010年知识产出

	The significance of anisotropic signals hiding in the Type Ia supernovae
	Lin, HN ; Li, X 1; Chang, Z 2
刊名	MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
	2016
卷号	460 期号:1 页码:617-626
关键词	supernovae: general FINE-STRUCTURE CONSTANT large-scale structure of Universe LAMBDA-CDM COSMOLOGICAL CONSTRAINTS PREFERRED DIRECTION HUBBLE DIAGRAM UNIVERSE EXPANSION GALAXIES ISOTROPY MODEL
DOI	http://dx.doi.org/10.1093/mnras/stw995
英文摘要	We use two different methods, i.e. dipole-fitting (DF) and hemisphere comparison (HC), to search for the anisotropic signals hiding in the Union2.1 data set. We find that the directions of maximum matter density derived using these two methods are about 114A degrees away from each other. We construct four Union2.1-like mock samples to test the statistical significance of these two methods. It is shown that DF method is statistically significant, while HC method is strongly biased by the distribution of data points in the sky. Then we assume that the anisotropy of distance modulus is mainly induced by the anisotropy of matter density, which is modelled to be the dipole form Omega(M) = Omega(M0)(1 - cos theta). We fit our model to Union2.1, and find that the direction of maximum matter density is well consistent with the direction derived using DF method, but it is very different from the direction previously claimed. Monte Carlo simulations show that our method is statistically more significant than HC method, although it is not as significant as DF method. The statistical significance can be further improved if the data points are homogeneously distributed in the sky. Due to the low quality of present supernovae data, however, it is still premature to claim that the Universe has any preferred direction.
学科主题	Astronomy & Astrophysics
语种	英语
资助机构	National Natural Science Fund of China (NSFC) [11305181, 11547305] ; State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China [Y5KF181CJ1] ; NSFC [11375203]
内容类型	期刊论文
源URL	[http://ir.itp.ac.cn/handle/311006/23368]
专题	理论物理研究所_理论物理所1978-2010年知识产出
作者单位	1.Chongqing Univ, Dept Phys, Chongqing 401331, Peoples R China 2.Chinese Acad Sci, Inst Theoret Phys, State Key Lab Theoret Phys, Beijing 100190, Peoples R China 3.Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Lin, HN,Li, X,Chang, Z. The significance of anisotropic signals hiding in the Type Ia supernovae[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2016,460(1):617-626.
APA	Lin, HN,Li, X,&Chang, Z.(2016).The significance of anisotropic signals hiding in the Type Ia supernovae.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,460(1),617-626.
MLA	Lin, HN,et al."The significance of anisotropic signals hiding in the Type Ia supernovae".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 460.1(2016):617-626.