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Redshift distortion of galaxy clustering and BIGBOSS. Yipeng Jing Shanghai Astronomical Observatory. f = b L . Compression parameter (Kaiser 1987). Line of sight to observer. Redshift-space galaxy-galaxy correlation function (r p , ).
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Redshift distortion of galaxy clustering and BIGBOSS Yipeng Jing Shanghai Astronomical Observatory
f = bL Compression parameter (Kaiser 1987) Line of sight to observer Redshift-space galaxy-galaxy correlation function (rp,) Pair separation perpendicular to line-of-sight rp(h-1 Mpc) Full distortions, including small-scale “spindle” due to clusters of galaxies, m=0.25, =0.75 No redshift distortions s Pair separation along line-of-sight (h-1 Mpc) rp Linear distortions only, flattening proportional to growth rate: depends on amount and kind of dark matter and dark energy
Jing, Mo, Boerner 1998 Mo, Jing, Boerner 1993 Li, Jing, Kauffmann, Boerner, White, Cheng 2006 Jing, Boerner 2004
Observational Probes of dark energy • Supernovae M(z) • Baryonic Acoustic Oscillations (BAO) • Abundance of rich clusters • Weak Lensing • Redshift distortion
So, the equation of state is not the end of the story… Cosmic acceleration can also be explained by modifying the theory of gravity [as e.g. in f(R) theories, Capozziello et al. 2005, or in multi-dimensional “braneworld” models, Dvali et al. (DGP) 2000]. How to distinguish between these two options, observationally? Growth of linear density fluctuations in the expanding Universe (in GR): which has a growing solution: from which we define agrowth rate • The growth equation (and thus the growth rate) depends not only on the expansion history H(t) (and thus on w) but also on the gravitation theory (e.g. Lue et al. 2004)
4个引力模型: GR,f(R),DGP,TeVeS 张鹏杰等提出在宇宙学 尺度上检验广义相对论与其 他引力论的新方法
通过EG方法,广义相对论在一亿光年尺度上得到了确认通过EG方法,广义相对论在一亿光年尺度上得到了确认 • Reyes et al. (Nature,464, 256-258,11 March 2010) 应用我们的EG方法分析了SDSS星系巡天的数据。 • 右图即为其主要结果。测量到的一亿光年尺度上的EG与广义相对论的预言相符。 • 该结果基本排除了TeVeS修改引力,并有力限制对f(R)引力
We also consider the dependence on the information used: the full galaxy power spectrum P(k), P(k) marginalized over its shape, or just the Baryon Acoustic Oscillations (BAO). We find that the inclusion of growth rate information (extracted using redshift space distortion and galaxy clustering amplitude measurements) leads to a factor of 3 improvement in the FoM, assuming general relativity is not modified. This inclusion partially compensates for the loss of information when only the BAO are used to give geometrical constraints, rather than using the full P(k) as a standard ruler. We
A proposal of DOE-NSF Stage IV ground-based dark energy experiment (the first?) the 4-m Mayall telescope at Kitt Peak, conditionally approved by NOAO
China’s participation Positioner: the department of Precision Instruments, USTC Science: USTC/Astronomy; Shanghai Astronomical Observatory; and other institutes can be included
Science Impact of BigBOSS • Key Project—dark energy • Community-Led Archival Science from Key Project ----galaxy evolution, clustering, environment…… • Community-Led Synchronous Science from Key Project (unused 15% fibers) • Community-Led PI Projects and Other Surveys (not with the Key Project)
our interested topics(incomplete list) • Dark energy: BAO, redshift distortion, high-order CFs etc; • Cross correlation with other samples: SZ, weak lensing, ISW etc • Evolution of galaxies: HODs at high redshift, etc • AGNs…. (USTC) • Welcome suggestions and more Chinese to participate