Detailed cluster lensing profiles at large radii and the impact on cluster weak lensing studies

By M. Oguri, T. Hamana. 2011

138 citations recorded by the source corpus.

Using a large set of ray tracing in N-body simulations, we examine lensing profiles around massive dark haloes in detail, with a particular emphasis on the profile at around the virial radii. We compare radial convergence profiles, which are measured accurately in the ray-tracing simulations by stacking many dark haloes, with our simple analytic model predictions. Our analytic models consist of a main halo, which is modelled by the Navarro–Frenk–White (NFW) density profile with three different forms of the truncation, plus the correlated matter (two-halo term) around the main halo. We find that the smoothly truncated NFW profile best reproduces the simulated lensing profiles, out to more than 10 times the virial radius. We then use this analytic model to investigate potential biases in cluster weak lensing studies in which a single, untruncated NFW component is usually assumed in interpreting observed signals. We find that cluster masses, inferred by fitting reduced tangential shear profiles with the NFW profile, tend to be underestimated by ∼5–10 per cent if fitting is performed out to ∼10–30 arcmin. In contrast, the concentration parameter is overestimated typically by ∼20 per cent for the same fitting range. We also investigate biases in computing the signal-to-noise ratio of weak lensing mass peaks, finding them to be ≲4 per cent for significant mass peaks. In the appendices, we provide useful formulae for the smoothly truncated NFW profile.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/6ac0a30146f10724014ea3f871c8b45e9f5b924a

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Citations in the corpus

DEPENDENCE OF THE OUTER DENSITY PROFILES OF HALOS ON THEIR MASS ACCRETION RATE (2014, methodology): “For example, Becker & Kravtsov (2011) showed that typical cluster-sized halos exhibit deviations from the NFW form, and that NFW profile fits to shear profiles extended to large radii can result in sizeable systematic bias in weak lensing mass measurements (see also Oguri & Hamana 2011).”
Quantifying baryon effects on the matter power spectrum and the weak lensing shear correlation (2018, methodology): “[24] based on fits to haloes assuming free and fixed concentrations (see figure 1 and subsequent text in ref.”
Weighing the Giants - I. Weak-lensing masses for 51 massive galaxy clusters: project overview, data analysis methods and cluster images (2012, methodology): “For the NFW profile (or closely related profiles), this has recently been done by a number of groups (Becker & Kravtsov 2011; Oguri & Hamana 2011; Bahé et al. 2012).”
Weighing the Giants – III. Methods and measurements of accurate galaxy cluster weak-lensing masses (2012, methodology): “We find that the BMO-2 profile returns a mean cluster mass 2% smaller than the NFW profile, with mass and redshift dependence.”
Robust weak-lensing mass calibration of Planck galaxy clusters (2014, methodology): “…by fitting an NFW profile over the radial range used in the WtG study (which does not exceed the cluster virial radii nor extend too close to the cluster centers) should be nearly unbiased for systems in the mass range probed here (Oguri & Hamana 2011; Becker & Kravtsov 2011; Bahé et al. 2012).”
Observational probes of cosmic acceleration (2012, background): “Cunha et al. (2009) and Oguri and Hamana (2011) show that this approach allows the mass and redshift dependence of 〈lnX|M,z〉 and Var(lnX|M,z) to be parameterized in an extremely flexible way while retaining enough information to yield strong cosmological constraints.”
CLASH: JOINT ANALYSIS OF STRONG-LENSING, WEAK-LENSING SHEAR, AND MAGNIFICATION DATA FOR 20 GALAXY CLUSTERS (2015, methodology): “We employ the radial dependence of the projected NFW profiles given by Wright & Brain- erd (2000), which provides a good description of the projected mass distribution in the one-halo regime, at least in an ensemble-average sense (Oguri & Hamana 2011; Umetsu et al. 2011a; Okabe et al. 2013).”
The Simons Observatory: science goals and forecasts (2018, methodology): “2.6, by assuming 20 galaxies per square arcminute with the dNg/dz from Oguri and Hamana (2011), dNg dz = z2 2z30 exp ( − z z0 ) , (27) where z0 = 1/3 that corresponds to the mean redshift zm = 1.”
Combined strong and weak lensing analysis of 28 clusters from the Sloan Giant Arcs Survey (2011, background): “Given the uncertainty from the non-linearity of the reduced shear and the the possible bias coming from the uncertainty of the outer mass profile (Oguri & Hamana 2011; Becker & Kravtsov 2011), we restrict tangential shear fitting in the range 0.158h−1Mpc < r < 3.16h−1Mpc.”
CLASH: WEAK-LENSING SHEAR-AND-MAGNIFICATION ANALYSIS OF 20 GALAXY CLUSTERS (2014, methodology): “…2 (Baltz et al. 2009, BMO): ρBMO(r) = ρs (r/rs)(1 + r/rs)2 [ 1 1 + (r/rt)2 ]2 (30) with rt = 2.6rvir(∼ 3r200c) the truncation radius, where the ratio of the truncation to virial radius, τv ≡ rt/rvir, is fixed to the typical value for cluster-sized halos in the ΛCDM cosmology (Oguri & Hamana 2011).”
THE CLUSTER LENSING AND SUPERNOVA SURVEY WITH HUBBLE: AN OVERVIEW (2011, background): “Deviations of cluster mass profiles from NFW or Einasto forms at small and/or large radii may slightly bias concentration measurements (Oguri & Hamana 2011).”
The Canadian Cluster Comparison Project: detailed study of systematics and updated weak lensing masses (2015, background): “Oguri & Hamana (2011) show that such a two-halo term dominates over the NFW profile on large scales.”