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B. Kubik

Publications and source records attributed to B. Kubik.

202 records · Page 12Linked to original sources

Euclid preparation: V. Predicted yield of redshift 7<z<9 quasars from the wide survey

We provide predictions of the yield of $7 8$ may be selected from Euclid $OYJH$ photometry alone, but selection over the redshift interval $7 7.5$ should be found in the DR1 data release, expected in 2024. It will be possible to determine the bright-end slope of the QLF, $7<z<8$, $M_{1450}<-25$, using 8m class telescopes to confirm candidates, but follow-up with JWST or E-ELT will be required to measure the faint-end slope. Contamination of the candidate lists is predicted to be modest even at $J_{AB}\sim23$. The precision with which $k$ can be determined over $7<z<8$ depends on the value of $k$, but assuming $k=-0.72$ it can be measured to a 1 sigma uncertainty of 0.07.

astro-ph.GA↗

Euclid preparation: VI. Verifying the Performance of Cosmic Shear Experiments

Our aim is to quantify the impact of systematic effects on the inference of cosmological parameters from cosmic shear. We present an end-to-end approach that introduces sources of bias in a modelled weak lensing survey on a galaxy-by-galaxy level. Residual biases are propagated through a pipeline from galaxy properties (one end) through to cosmic shear power spectra and cosmological parameter estimates (the other end), to quantify how imperfect knowledge of the pipeline changes the maximum likelihood values of dark energy parameters. We quantify the impact of an imperfect correction for charge transfer inefficiency (CTI) and modelling uncertainties of the point spread function (PSF) for Euclid, and find that the biases introduced can be corrected to acceptable levels.

astro-ph.CO↗

An estimation of the Local growth rate from Cosmicflows-3 peculiar velocities

This article explores three usual estimators, noted as $v_{12}$ of the pairwise velocity, $ψ_1$ and $ψ_2$ of the observed two-point galaxy peculiar velocity correlation functions. These estimators are tested on mock samples of {\it Cosmicflows-3} dataset \citep{Tully:2016aa} , derived from a numerical cosmological simulation, and also on a number of constrained realizations of this dataset. Observational measurements errors and cosmic variance are taken into consideration in the study. The result is a local measurement of $f σ_8 = 0.43 \left( \pm 0.03 \right)_\mathrm{obs} \left( \pm 0.11 \right)_\mathrm{cosmic}$ out to $z=0.05$, in support of a $Λ$CDM cosmology.

astro-ph.CO↗

Even tiers and resonances on the Real Projective Plane

In this work we focus on various phenomenological aspects of the lightest even tiers, (2,0) and (0,2), in models based on a Real Projective Plane in 6 dimensions. We discuss the spectrum of the levels due to loop corrections, and the limit when the two radii are equal, in which case the two levels mix with each other and a new basis is defined. We also discuss the dependence of the spectrum on the ratio of the two radii. These results are essential to understand the phenomenology of the model at colliders (LHC) and to predict the relic abundance of Dark Matter. Finally, we estimate the bounds on the radius from resonant decays of the even tiers at the LHC, showing that they can be in the 600 GeV range after the complete analysis of the 2011 data.

hep-ph↗