English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The Sloan Digital Sky Survey has surveyed 14,555 square degrees of the sky,and delivered over a trillion pixels of imaging data. We present thelarge-scale clustering of 1.6 million quasars between z = 0.5 and z = 2.5 thathave been classified from this imaging, representing the highest density ofquasars ever studied for clustering measurements. This data set spans ~11,000square degrees and probes a volume of 80(Gpc/h)^3. In principle, such a largevolume and medium density of tracers should facilitate high-precisioncosmological constraints. We measure the angular clustering of photometricallyclassified quasars using an optimal quadratic estimator in four redshift sliceswith an accuracy of ~25% over a bin width of l ~10 - 15 on scales correspondingto matter-radiation equality and larger (l ~ 2 - 30). Observational systematicscan strongly bias clustering measurements on large scales, which can mimiccosmologically relevant signals such as deviations from Gaussianity in thespectrum of primordial perturbations. We account for systematics by employing anew method recently proposed by Agarwal et al. (2014) to the clustering ofphotometrically classified quasars. We carefully apply our methodology tomitigate known observational systematics and further remove angular bins thatare contaminated by unknown systematics. Combining quasar data with thephotometric luminous red galaxy (LRG) sample of Ross et al. (2011) and Ho etal. (2012), and marginalizing over all bias and shot noise-like parameters, weobtain a constraint on local primordial non-Gaussianity of fNL = -113+/-154(1\sigma error). [Abridged]

Sloan Digital Sky Survey III Photometric Quasar Clustering: Probing the Initial Conditions of the Universe using the Largest Volume