Toward a Precise Measurement of Matter Clustering: Lyα Forest Data at Redshifts 2-4

By R. Croft, D. Weinberg, M. Bolte, S. Burles, L. Hernquist, Neal Katz, D. Kirkman, D. Tytler. 2000

345 citations recorded by the source corpus.

We measure the filling factor, correlation function, and power spectrum of transmitted flux in a large sample of Lyα forest spectra, comprised of 30 Keck HIRES spectra and 23 Keck LRIS spectra. We infer the linear matter power spectrum P(k) from the flux power spectrum PF(k), using an improved version of the method of Croft et al. that accounts for the influence of redshift-space distortions, nonlinearity, and thermal broadening on the shape of PF(k). The evolution of the shape and amplitude of P(k) over the redshift range of the sample (z ≈ 2-4) is consistent with the predictions of gravitational instability, implying that nongravitational fluctuations do not make a large contribution to structure in the Lyα forest. Our fiducial measurement of P(k) comes from a subset of the data with 2.3 < z < 2.9, mean absorption redshift ⟨z⟩ = 2.72, and total path length Δz ≈ 25. It has a dimensionless amplitude Δ2(kp) = 0.74 at wavenumber kp = 0.03 (km s-1)-1 and is well described by a power law of index ν = -2.43 ± 0.06 or by a CDM-like power spectrum with shape parameter Γ′ = 1.3 × 10-3 (km s-1)-1 at z = 2.72 (all error bars 1 σ). The correspondence to present-day P(k) parameters depends on the adopted cosmology. For Ωm = 0.4, ΩΛ = 0.6, the best-fit shape parameter is Γ = 0.16 h Mpc-1, in good agreement with measurements from the 2dF Galaxy Redshift Survey, and the best-fit normalization is σ8 = 0.82(Γ/0.15)-0.44. Matching the observed cluster mass function and our measured Δ2(kp) in spatially flat cosmological models requires Ωm = 0.38 + 2.2(Γ - 0.15). Matching Δ2(kp) in COBE-normalized, flat CDM models with no tensor fluctuations requires Ωm = (0.29 ± 0.04)n-2.89 h, and models that satisfy this constraint are also consistent with our measured logarithmic slope. The Lyα forest complements other observational probes of the linear matter power spectrum by constraining a regime of redshift and length scale not accessible by other means, and the consistency of these inferred parameters with independent estimates provides further support for a cosmological model based on inflation, cold dark matter, and vacuum energy.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/7c35f7a424de16f08899ae20ea0e4f2fec1269fa

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

Citations in the corpus

The Relation between Quasar and Merging Galaxy Luminosity Functions and the Merger-driven Star Formation History of the Universe (2006, background): “Large-scale cosmological simulations (e.g., Cen et al. 1994; Zhang et al. 1995; Hernquist et al. 1996; Katz et al. 1996a, 1996b; Navarro et al. 1996; Croft et al. 1998, 1999, 2002; Davé et al. 1999; McDonald et al. 2000, 2006; Hui et al. 2001; Viel et al. 2003, 2004) and semianalytic models (e.g.,…”
“Non-cold” dark matter at small scales: a general approach (2017, neutral): “[24, 84]): this motivates the application of Eq.”
Toward a Measurement of the Cosmological Geometry at z ~ 2: Predicting Lyα Forest Correlation in Three Dimensions and the Potential of Future Data Sets (2001, methodology): “…5% in the ratio of power along to across the line of sight on large scales, equivalent to a similar variation in , is actually not a problem for the AP test because the measurements by McDonald et al. (2000) and Croft et al. (2002) already constrain the power spectrum amplitude to better than 20%.”
A DEFINITIVE SURVEY FOR LYMAN LIMIT SYSTEMS AT z ∼ 3.5 WITH THE SLOAN DIGITAL SKY SURVEY (2009, background): “…constrained cosmological parameters such as the primordial power spectrum and the baryonic mass density and astrophysical parameters like the amplitude of the ionizing background (e.g. Rauch 1998; Croft et al. 2002; McDonald et al. 2005; Tytler et al. 2004; Faucher-Giguère et al. 2008b).”
Constraints on neutrino masses from Lyman-alpha forest power spectrum with BOSS and XQ-100 (2017, methodology): “troduction The ﬂux power spectrum of the Lyman-(Ly) forest in quasar absorption spectra is a powerful tool to study clustering in the Universe at redshifts ˘2 to 4, on scales ranging from a few Mpc [1,5,6] to hundreds of Mpc [7–9]. Compared to a model derived from a set of dedicated hydrodynamical s”