Evolution of adiabatic irregularities during the recombination era, and the missing mass in the universe

Journal Article · Mon Jul 01 00:00:00 EDT 1985 · Sov. Astron. (Engl. Transl.); (United States)

OSTI ID:6059771

Zabotin, N A; Nasel'skii, P D

Primordial carriers of missing mass in the universe, such as finite-mass neutrinos, heavy (m/sub L/> or approx. =1 GeV) neutral leptons, or black holes, may have contributed to the evolution of pregalactic adiabatic irregularities during the cosmological era of hydrogen recombination. Equations previously derived by the authors are applied to a three-component (baryons, radiation, heavy but weakly interacting particles) model medium; dissipative effects are analyzed numerically, and the plasma velocity field is calculated at the epoch of decoupling. In a model with three massive-neutrino species (..nu../sub e/, ..nu../sub ..mu../, ..nu../sub tau/) of equal mass (roughly-equal30 eV) and thermodynamic number density, the perturbations in the plasma density when the redshift zroughly-equal10/sup 3/ would amount to 0.1% at most. If instead the gravitating-particle background consists of stable heavy leptons or primordial black holes, the maximum density contrast will be an order of magnitude lower. The gravitation of any density fluctuations in the ordinary collisional matter during the recombination and post-recombination eras will serve to modulate the amplitude of the small-scale part of the spectrum of inhomogeneities occurring in a background of massive neutrinos.

• Research Organization: Institute of Physics, Rostov University
• OSTI ID: 6059771
• Journal Information: Sov. Astron. (Engl. Transl.); (United States), Vol. 29:4
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC NEUTRINOS
MASS
COSMOLOGICAL MODELS
FLUCTUATIONS
MISSING MASS
UNIVERSE
COSMOLOGY
ADIABATIC PROCESSES
DENSITY
ELEMENTARY PARTICLES
GRAVITATION
RELICT RADIATION
THERMODYNAMICS
COSMIC RADIATION
ELECTROMAGNETIC RADIATION
FERMIONS
IONIZING RADIATIONS
LEPTONS
MASSLESS PARTICLES
MATHEMATICAL MODELS
MICROWAVE RADIATION
NEUTRINOS
PHYSICAL PROPERTIES
RADIATIONS
VARIATIONS
640106* - Astrophysics & Cosmology- Cosmology