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arXiv 1104.1444astro-ph.CO
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SNLS3:结合超新星遗留调查三年数据和其他探测器对暗能量的限制

SNLS3: Constraints on Dark Energy Combining the Supernova Legacy Survey Three Year Data with Other Probes

M. Sullivan, J. Guy, A. Conley, N. Regnault, P. Astier, C. Balland, S. Basa, R. G. Carlberg, D. Fouchez, D. Hardin, I. M. Hook, D. A. Howell, R. Pain, N. Palanq… 展开作者

M. Sullivan, J. Guy, A. Conley, N. Regnault, P. Astier, C. Balland, S. Basa, R. G. Carlberg, D. Fouchez, D. Hardin, I. M. Hook, D. A. Howell, R. Pain, N. Palanque-Delabrouille, K. M. Perrett, C. J. Pritchet, J. Rich, V. Ruhlmann-Kleider, D. Balam, S. Baumont, R. S. Ellis, S. Fabbro, H. K. Fakhouri, N. Fourmanoit, S. Gonzalez-Gaitan, M. L. Graham, M. J. Hudson, E. Hsiao, T. Kronborg, C. Lidmam, A. M. Mourao, J. D. Neill, S. Perlmutter, P. Ripoche, N. Suzuki, E. S. Walker

摘要:

我们使用Guy et al.(2010)和Conley et al.(2011)的超新星遗产调查三年样本(SNLS 3)提出了对暗能量性质的观测约束。我们使用的472超新星Ia在这个样本中,占最近发现的超新星Ia光度和宿主星系属性之间的相关性,并包括所有确定的系统不确定性的影响直接在宇宙学拟合。将SNLS 3数据与完整的WMAP 7功率谱、斯隆数字巡天明亮的红色星系功率谱以及来自SHOES的哈勃常数H 0的先验相结合,在平坦的宇宙中,我们发现omega_m=0.269+/-0.015和w=-1.061+0.069-0.068 --暗能量状态方程参数w的6.5%测量值。统计和系统的不确定性是大致相等的,与系统的不确定性占主导地位的光度校准的超新星Ia通量-没有这些校准的影响,系统贡献只有约2%的误差在w。当放松平坦性的假设时,我们发现ω_m=0.271+/-0.015,ω_k=-0.002+/-0.006,w=-1.069+0.091-0.092。在平坦宇宙中,将w的时间演化参数化为w(a)=w_0+w_a(1-a),得到w_0=-0.905+/-0.196,w_a=-0.984+1.094-1.097。我们所有的结果都与平坦的w=-1宇宙相一致。SNLS 3样本的大小允许根据其光变曲线和宿主星系的特性对SNe进行各种测试。我们发现,来自这些不同的子样本的宇宙学约束是一致的。有证据表明,与Ia型超新星光度和颜色相关的系数β,在大于4 sigma的显著性下随宿主参数而变化(除了已知的超新星光度-宿主关系之外);然而,这对宇宙学结果只有很小的影响,目前是一个次主导系统。

英文摘要:

We present observational constraints on the nature of dark energy using the Supernova Legacy Survey three year sample (SNLS3) of Guy et al. (2010) and Conley et al. (2011). We use the 472 SNe Ia in this sample, accounting for recently discovered correlations between SN Ia luminosity and host galaxy properties, and include the effects of all identified systematic uncertainties directly in the cosmological fits. Combining the SNLS3 data with the full WMAP7 power spectrum, the Sloan Digital Sky Survey luminous red galaxy power spectrum, and a prior on the Hubble constant H0 from SHOES, in a flat universe we find omega_m=0.269+/-0.015 and w=-1.061+0.069-0.068 -- a 6.5% measure of the dark energy equation-of-state parameter w. The statistical and systematic uncertainties are approximately equal, with the systematic uncertainties dominated by the photometric calibration of the SN Ia fluxes -- without these calibration effects, systematics contribute only a ~2% error in w. When relaxing the assumption of flatness, we find omega_m=0.271+/-0.015, omega_k=-0.002+/-0.006, and w=-1.069+0.091-0.092. Parameterizing the time evolution of w as w(a)=w_0+w_a(1-a), gives w_0=-0.905+/-0.196, w_a=-0.984+1.094-1.097 in a flat universe. All of our results are consistent with a flat, w=-1 universe. The size of the SNLS3 sample allows various tests to be performed with the SNe segregated according to their light curve and host galaxy properties. We find that the cosmological constraints derived from these different sub-samples are consistent. There is evidence that the coefficient, beta, relating SN Ia luminosity and color, varies with host parameters at >4sigma significance (in addition to the known SN luminosity--host relation); however this has only a small effect on the cosmological results and is currently a sub-dominant systematic.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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