Intrinsic alignments of SDSS-III BOSS LOWZ sample galaxies

By Sukhdeep Singh, Rachel Mandelbaum, S. More. 2014

159 citations recorded by the source corpus.

Intrinsic alignments (IA) of galaxies, i.e. correlations of galaxy shapes with each other (II) or with the density field (gI), are potentially a major astrophysical source of contamination for weak lensing surveys. We present the results of IA measurements of galaxies on 0.1–200h 1 Mpc scales using the SDSS-III BOSS LOWZ sample, in the redshift range 0.16 < z < 0.36. We extend the existing IA measurements for spectroscopic LRGs to lower luminosities, and show that the luminosity dependence of large-scale IA can be well-described by a power law. Within the limited redshift and color range of our sample, we observe no significant redshift or color dependence of IA. We measure the halo mass of galaxies using galaxy-galaxy lensing, and show that the mass dependence of large-scale IA is also well described by a power law. We detect variations in the scale dependence of IA with mass and luminosity, which underscores the need to use flexible templates in order to remove the IA signal. We also study the environment dependence of IA by splitting the sample into field and group galaxies, which are further split into satellite and central galaxies. We show that group central galaxies are aligned with their halos at small scales and also are aligned with the tidal fields out to large scales. We also detect the radial alignments of satellite galaxies within groups. These results can be used to construct better intrinsic alignment models for removal of this contaminant to the weak lensing signal.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/8fc9a3acfeb56d3133e4de335ee46830e5b6bf18

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Citations in the corpus

Core Cosmology Library: Precision Cosmological Predictions for LSST (2018, methodology): “The NLA model has limitations in the modelling of small-scale correlations (Singh et al. 2015) and does not predict any B-mode contributions that can arise from nonlinearities at such scales.”
Galaxy Alignments: Observations and Impact on Cosmology (2015, methodology): “This result is consistent with the value of AI = (0.066 ± 0.008)ρ−1crit found by the more recent study by Singh et al. (2015), which we discuss below.”
Weak Lensing Measurement of the Mass--Richness Relation of SDSS redMaPPer Clusters (2016, methodology): “While this upper limit is comparable to our uncertainties, we note that IA remains undetected for typical satellite galaxy populations in galaxy clusters (e.g., Sifón et al. 2015), with detections only for LRGs (e.g., Singh et al. 2015).”
Galaxy Alignments: An Overview (2015, methodology): “The analyses have been carried out by several groups (Mandelbaum et al. 2006b; Hirata et al. 2007; Paz et al. 2008; Okumura et al. 2009; Joachimi et al. 2011; Lee 2011; Li et al. 2013; Singh et al. 2014), including in Joachimi et al.”
CFHTLenS revisited: assessing concordance with Planck including astrophysical systematics (2016, unknown): “For the informative case, we set η = 0 given the lack of evidence for redshift evolution in Joachimi et al. (2011) and Singh et al. (2015).”
Cosmology from cosmic shear power spectra with Subaru Hyper Suprime-Cam first-year data (2018, methodology): “This phenomenological model has been found to fit the galaxy-shear cross correlations down to >∼ 1− 2h−1Mpc quite well (Singh et al. 2015; Blazek et al. 2015), and has been used in various cosmic shear analyses (Heymans et al. 2013; Kitching et al. 2014; Abbott et al. 2016; Hildebrandt et al. 2017).”