arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0904.2218astro-ph.CO
收藏

从重子声学振荡澄清暗能量约束的预测

Clarifying Forecasts of Dark Energy Constraints from Baryon Acoustic Oscillations

Yun Wang

备注：
10 pages, 10 color figures. Text revised for clarification. Results unchanged
发表信息：
Mod.Phys.Lett.A25:3093-3113,2010
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

通过星系红移巡天测量重子声学振荡（BAO）是探测暗能量最有前途的方法之一。在本文中，我们澄清的假设，进入预测的暗能量约束BAO。我们表明，假设一个常数nP_{0.2} /G^2（z）（其中P_{0.2}是在k= 0.2 h/Mpc和红移z的真实空间星系功率谱）给出了一个很好的近似的观测星系数密度从一个现实的流量有限的星系红移调查预期。我们发现，假设nP_{0.2} /G^2（z）=10，得到的暗能量约束与假设nP_{0.2} =3非常相似，但后者对应的星系数密度在z=2时要大70%左右。我们展示了约束暗能量的品质因数（FoM）如何依赖于假设的星系数密度、红移精度、红移范围、测量区域以及由于非线性演化和星系偏置理论中的校准和不确定性引起的系统误差。我们发现，高达0.4-0.5%的dz=0.1红移切片的加性系统噪声不会导致显着减少的BAO FoM。

英文摘要：

The measurement of baryon acoustic oscillations (BAO) from a galaxy redshift survey provides one of the most promising methods for probing dark energy. In this paper, we clarify the assumptions that go into the forecasts of dark energy constraints from BAO. We show that assuming a constant nP_{0.2}/G^2(z) (where P_{0.2} is the real space galaxy power spectrum at k=0.2h/Mpc and redshift z) gives a good approximation of the observed galaxy number density expected from a realistic flux-limited galaxy redshift survey. We find that assuming nP_{0.2}/G^2(z)=10 gives very similar dark energy constraints to assuming nP_{0.2}=3, but the latter corresponds to a galaxy number density larger by ~70% at z=2. We show how the Figure-of-Merit (FoM) for constraining dark energy depends on the assumed galaxy number density, redshift accuracy, redshift range, survey area, and the systematic errors due to calibration and uncertainties in the theory of nonlinear evolution and galaxy biasing. We find that an additive systematic noise of up to 0.4-0.5% per dz=0.1 redshift slice does not lead to significant decrease in the BAO FoM.

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。

↑