Evidence of the accelerated expansion of the Universe from weak lensing tomography with COSMOS

By T. Schrabback, J. Hartlap, B. Joachimi, M. Kilbinger, P. Simon, K. Benabed, Maruvsa Bradavc, T. Eifler, T. Erben, C. Fassnacht and 12 more. 2009

299 citations recorded by the source corpus.

We present a comprehensive analysis of weak gravitational lensing by large-scale structure in the Hubble Space Telescope Cosmic Evolution Survey (COSMOS), in which we combine space-based galaxy shape measurements with ground-based photometric redshifts to study the redshift dependence of the lensing signal and constrain cosmological parameters. After applying our weak lensing-optimized data reduction, principal-component interpolation for the spatially, and temporally varying ACS point-spread function, and improved modelling of charge-transfer inefficiency, we measured a lensing signal that is consistent with pure gravitational modes and no significant shape systematics. We carefully estimated the statistical uncertainty from simulated COSMOS-like fields obtained from ray-tracing through the Millennium Simulation, including the full non-Gaussian sampling variance. We tested our lensing pipeline on simulated space-based data, recalibrated non-linear power spectrum corrections using the ray-tracing analysis, employed photometric redshift information to reduce potential contamination by intrinsic galaxy alignments, and marginalized over systematic uncertainties. We find that the weak lensing signal scales with redshift as expected from general relativity for a concordance ACDM cosmology, including the full cross-correlations between different redshift bins. Assuming a flat ACDM cosmology, we measure σ 8 (Ω m /0.3) 0.51 = 0.75 ± 0.08 from lensing, in perfect agreement with WMAP-5, yielding joint constraints Ω m = 0.266 +0.025 -0.023 σ 8 = 0.802 +0.028 -0.029 (all 68.3% conf.). Dropping the assumption of flatness and using priors from the HST Key Project and Big-Bang nucleosynthesis only, we find a negative deceleration parameter q 0 at 94.3% confidence from the tomographic lensing analysis, providing independent evidence of the accelerated expansion of the Universe. For a flat ωCDM cosmology and prior ω ∈ [-2, 0], we obtain ω < -0.41 (90% conf.). Our dark energy constraints are still relatively weak solely due to the limited area of COSMOS. However, they provide an important demonstration of the usefulness of tomographic weak lensing measurements from space.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/efc5c02e5524af77bc97f9285a561380df099b70

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Citations in the corpus

Weighing the Giants - I. Weak-lensing masses for 51 massive galaxy clusters: project overview, data analysis methods and cluster images (2012, methodology): “In the regime where the average shear measurement bias does not depend on (S/N)STEP, we test for dependence on the size of the object (in units of PSF size, Fig.”
Quantifying the effect of baryon physics on weak lensing tomography (2011, methodology): “The cosmic shear signal has been measured using large ground-based surveys (e.g., Hoekstra et al. 2006; Fu et al. 2008) and from space (e.g., Massey et al. 2007; Schrabback et al. 2010).”
KiDS+VIKING-450: Cosmic shear tomography with optical and infrared data (2018, methodology): “19 The impact of such catastrophic redshifts outliers on weak lensing studies has already been investigated in Schrabback et al. (2010) and Schrabback et al. (2018) for earlier photo-zs from COSMOS (Ilbert et al. 2009) and 3D-HST (Skelton et al. 2014). the tension with Planck, possibly solidifying…”
The effects of galaxy formation on the matter power spectrum: a challenge for precision cosmology (2011, background): “…most accurate measurements of the matter power spectrum come from studies of weak, gravitational lensing (e.g. Massey et al. 2007; Fu et al. 2008; Schrabback et al. 2010), galaxy clustering (e.g. Cole et al. 2005; Reid et al. 2010) and the Lyα forest (e.g. Viel et al. 2004; McDonald et al. 2006).”
CFHTLenS: testing the laws of gravity with tomographic weak lensing and redshift-space distortions (2012, methodology): “The mean values of µ0, Σ0, and w all change by less than 0.02 when the prescription from Schrabback et al. (2010) is omitted, which is well within our statistical errors.”
THE ATACAMA COSMOLOGY TELESCOPE: COSMOLOGY FROM GALAXY CLUSTERS DETECTED VIA THE SUNYAEV–ZEL'DOVICH EFFECT (2010, background): “These largely consist of observing the weak and strong lensing of background sources by intervening matter (e.g., Schrabback et al. 2010), measuring distortions in redshift space with spectroscopic surveys of galaxies (e.g., Simpson & Peacock 2010), and quantifying the abundance of galaxy clusters…”
Weighing the giants – IV. Cosmology and neutrino mass (2014, background): “…= 0.74± 0.03 (again at fixed Ωm = 0.3) from a 2-dimensional cosmic shear analysis of CFHTLenS data.24 The tomographic lensing analysis of HST COSMOS data by Schrabback et al. (2010) yields a value of 0.75±0.08, which is nominally lower than our constraints, but consistent within the uncertainties.”
Origins of weak lensing systematics, and requirements on future instrumentation (or knowledge of instrumentation) (2012, methodology): “This procedure has a long heritage in Hubble Space Telescope (HST) analyses (e.g. Rhodes et al. 2004; Miralles et al. 2004; Rhodes et al. 2007; Jee et al. 2007; Schrabback et al. 2010; Jee et al. 2011; Hoekstra et al. 2011).”
Combined strong and weak lensing analysis of 28 clusters from the Sloan Giant Arcs Survey (2011, background): “First, we adopt the functional form proposed by Schrabback et al. (2010): p(z|i) ∝ ( z z0 )α ( exp [ − ( z z0 )β ] + cud exp [ − ( z z0 )γ] ) , (9) with u = max(0, i − 23) and (α, β, c, d, γ)=(0.678, 5.606, 0.581, 1.851, 1.464).”
Bayesian galaxy shape measurement for weak lensing surveys – III. Application to the Canada–France–Hawaii Telescope Lensing Survey (2012, methodology): “To date, imaging data obtained from the Hubble Space Telescope (HST) have been the most successful in this respect, but have yielded accurate cosmological results only relatively recently (e.g. Schrabback et al. 2010).”
NEW CONSTRAINTS ON THE EVOLUTION OF THE STELLAR-TO-DARK MATTER CONNECTION: A COMBINED ANALYSIS OF GALAXY–GALAXY LENSING, CLUSTERING, AND STELLAR MASS FUNCTIONS FROM z = 0.2 to z = 1 (2011, methodology): “Schrabback et al. (2010) found that VAFACTOR partially correlates with the higherorder PSF variations, motivating our use of this quantity.”
The Intrinsic Alignment of Galaxies and its Impact on Weak Gravitational Lensing in an Era of Precision Cosmology (2014, methodology): “Several surveys have already provided cosmic shear measurements and put complementary constraints on cosmological parameters (Bacon et al., 2000; van Waerbeke et al., 2000; Rhodes et al., 2001; Hoekstra et al., 2002; van Waerbeke et al., 2002; Brown et al., 2003; Jarvis et al., 2003; Massey et al., ”
Cosmological parameter constraints from galaxy-galaxy lensing and galaxy clustering with the SDSS DR7 (2012, background): “…a decade ago (Bacon et al. 2000; Van Waerbeke et al. 2000; Rhodes et al. 2001; Hoekstra et al. 2002), increasingly enlarging datasets and sophisticated measurement techniques have led to steadily decreasing errors, both statistical and systematic (e.g., Schrabback et al. 2010; Heymans et al. 2013).”
CFHTLenS tomographic weak lensing cosmological parameter constraints: Mitigating the impact of intrinsic galaxy alignments (2013, methodology): “For dark energy cosmologies, where the equation of state of dark energy parameter, w0 6= −1, a modulation of the non-linear power is required (McDonald et al. 2006) which we apply using of the scaling correction from Schrabback et al. (2010); Refregier et al. (2011).”
Weak Gravitational Lensing (2012, background): “[4, 76]) to improve the constraints on cosmological parameters.”