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Neutrino Masses (neutrino + mass)

Distribution by Scientific Domains
Physics and Astronomy100%

Selected Abstracts

Neutrino physics beyond neutrino masses

FORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 7-9 2010
F. del Aguila
Abstract We briefly summarise the current status of neutrino masses and mixing, paying special attention to the prospects for observing new leptonic interactions. [source]

MOND plus classical neutrinos are not enough for cluster lensing

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2008
Priyamvada Natarajan
ABSTRACT Clusters of galaxies offer a robust test bed for probing the nature of dark matter that is insensitive to the assumption of the gravity theories. Both Modified Newtonian Dynamics (MOND) and General Relativity (GR) would require similar amounts of non-baryonic matter in clusters as MOND boosts the gravity only mildly on cluster scales. Gravitational lensing allows us to estimate the enclosed mass in clusters on small (,20,50 kpc) and large (,several 100 kpc) scales independent of the assumptions of equilibrium. Here, we show for the first time that a combination of strong and weak gravitational lensing effects can set interesting limits on the phase-space density of dark matter in the centres of clusters. The phase-space densities derived from lensing observations are inconsistent with neutrino masses ranging from 2,7 eV, and hence do not support the 2 eV-range particles required by MOND. To survive, the most plausible modification for MOND may be an additional degree of dynamical freedom in a covariant incarnation. [source]

Beating lensing cosmic variance with galaxy tomography

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2004
Ue-Li Pen
ABSTRACT We discuss the use of cross-correlations between galaxies with distance information and projected weak lensing dark matter maps to obtain a fully three-dimensional dark matter map and power spectrum. On large scales (l, 100) one expects the galaxies to be biased, but not stochastic. I show that this allows a simultaneous solution of the full three-dimensional evolving galaxy bias and the dark matter power spectrum simultaneously. Within the photometric redshift information of the Canada,France,Hawaii (CFH) lensing legacy survey, this allows a threefold reduction of statistical error, while a cross-correlation with the Canadian Large Adaptive Reflector (CLAR) or other deep spectroscopic surveys allows a tenfold improvement in dark matter power accuracy on linear scales. This makes lensing surveys more sensitive to the cosmic equation of state and the neutrino masses. [source]