Cosmology with the pairwise kinematic SZ effect: Calibration and validation using hydrodynamical simulations

Kavli Affiliate: George Efstathiou | First 5 Authors: Bjoern Soergel, Alexandro Saro, Tommaso Giannantonio, George Efstathiou, Klaus Dolag | Summary: We study the potential of the kinematic SZ effect as a probe for cosmology, focusing on the pairwise method. The main challenge is disentangling the cosmologically interesting mean pairwise velocity from the cluster optical depth […]


Continue.. Cosmology with the pairwise kinematic SZ effect: Calibration and validation using hydrodynamical simulations

The Discovery of a Five-Image Lensed Quasar at z = 3.34 using PanSTARRS1 and Gaia

Kavli Affiliate: R. G. McMahon | First 5 Authors: Fernanda Ostrovski, Cameron A. Lemon, Matthew W. Auger, Richard G. McMahon, Christopher D. Fassnacht | Summary: We report the discovery, spectroscopic confirmation, and mass modelling of the gravitationally lensed quasar system PS J0630-1201. The lens was discovered by matching a photometric quasar catalogue compiled from Pan-STARRS […]


Continue.. The Discovery of a Five-Image Lensed Quasar at z = 3.34 using PanSTARRS1 and Gaia

The Discovery of a Five-Image Lensed Quasar at z = 3.34 using PanSTARRS1 and Gaia

Kavli Affiliate: R. G. McMahon | First 5 Authors: Fernanda Ostrovski, Cameron A. Lemon, Matthew W. Auger, Richard G. McMahon, Christopher D. Fassnacht | Summary: We report the discovery, spectroscopic confirmation, and mass modelling of the gravitationally lensed quasar system PS J0630-1201. The lens was discovered by matching a photometric quasar catalogue compiled from Pan-STARRS […]


Continue.. The Discovery of a Five-Image Lensed Quasar at z = 3.34 using PanSTARRS1 and Gaia

Gravitationally Lensed Quasars in Gaia: I. Resolving Small-Separation Lenses

Kavli Affiliate: R. G. McMahon | First 5 Authors: Cameron A. Lemon, Matthew W. Auger, Richard G. McMahon, Sergey E. Koposov, | Summary: Gaia’s exceptional resolution (FWHM $sim$ 0.1$^{primeprime}$) allows identification and cataloguing of the multiple images of gravitationally lensed quasars. We investigate a sample of 49 known lensed quasars in the SDSS footprint, with […]


Continue.. Gravitationally Lensed Quasars in Gaia: I. Resolving Small-Separation Lenses

Gravitationally Lensed Quasars in Gaia: I. Resolving Small-Separation Lenses

Kavli Affiliate: R. G. McMahon | First 5 Authors: Cameron A. Lemon, Matthew W. Auger, Richard G. McMahon, Sergey E. Koposov, | Summary: Gaia’s exceptional resolution (FWHM $sim$ 0.1$^{primeprime}$) allows identification and cataloguing of the multiple images of gravitationally lensed quasars. We investigate a sample of 49 known lensed quasars in the SDSS footprint, with […]


Continue.. Gravitationally Lensed Quasars in Gaia: I. Resolving Small-Separation Lenses

Molecular gas in three z~7 quasar host galaxies

Kavli Affiliate: R. G. McMahon | First 5 Authors: Bram Venemans, Fabian Walter, Roberto Decarli, Carl Ferkinhoff, Axel Weiss | Summary: We present ALMA band 3 observations of the CO(6-5), CO(7-6), and [CI] 369micron emission lines in three of the highest redshift quasar host galaxies at 6.6<z<6.9. These measurements constitute the highest-redshift CO detections to […]


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Statistical Inconsistencies in the KiDS-450 Dataset

Kavli Affiliate: George Efstathiou | First 5 Authors: George Efstathiou, Pablo Lemos, , , | Summary: The Kilo-Degree Survey (KiDS) has been used in several recent papers to infer constraints on the amplitude of the matter power spectrum and matter density at low redshift. Some of these analyses have claimed tension with the Planck $Lambda […]


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A deep search for metals near redshift 7: the line-of-sight towards ULAS J1120+0641

Kavli Affiliate: R. G. McMahon | First 5 Authors: Sarah E. I. Bosman, George D. Becker, Martin G. Haehnelt, Paul C. Hewett, Richard G. McMahon | Summary: We present a search for metal absorption line systems at the highest redshifts to date using a deep (30h) VLT/X-Shooter spectrum of the z = 7.084 quasi-stellar object […]


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Dynamic nested sampling: an improved algorithm for parameter estimation and evidence calculation

Kavli Affiliate: Anthony Lasenby | First 5 Authors: Edward Higson, Will Handley, Mike Hobson, Anthony Lasenby, | Summary: We introduce dynamic nested sampling: a generalisation of the nested sampling algorithm in which the number of "live points" varies to allocate samples more efficiently. In empirical tests the new method significantly improves calculation accuracy compared to […]


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The effect of Limber and flat-sky approximations on galaxy weak lensing

Kavli Affiliate: George Efstathiou | First 5 Authors: Pablo Lemos, Anthony Challinor, George Efstathiou, , | Summary: We review the effect of the commonly-used Limber and flat-sky approximations on the calculation of shear power spectra and correlation functions for galaxy weak lensing. These approximations are accurate at small scales, but it has been claimed recently […]


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