Power Spectra of the Cosmic Microwave Background and Density Fluctuations Seeded by Local Cosmic Strings
نویسندگان
چکیده
We compute the power spectra in the cosmic microwave background and cold dark matter (CDM) fluctuations seeded by strings, using the largest string simulations performed so far. We find that local strings differ from global defects in that the scalar components of the stress-energy tensor dominate over vector and tensor components. This result has far reaching consequences. We find that cosmic strings exhibit a single Doppler peak of acceptable height at high ,. They also seem to have a less severe bias problem than global defects, although the CDM power spectrum in the “standard” cosmology is the wrong shape to fit large scale structure data. [S0031-9007(98)08249-0]
منابع مشابه
The power spectra of the cosmic microwave background and density fluctuations seeded by local cosmic strings
(1999) The power spectra of the cosmic microwave background and density fluctuations seeded by local cosmic strings. This document is made available in accordance with publisher policies and may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the URL above for details on accessing the p...
متن کاملCMB and LSS Power Spectra From Local Cosmic String Seeded Structure Formation
We evaluate the two point functions of the stress energy from the largest string simulations carried out so far. The two point functions are used to calculate the cosmic microwave background (CMB) and cold dark matter (CDM) power spectra from local cosmic string models for structure formation. We find that our spectra differ significantly from those previously calculated for both global and loc...
متن کاملCMB polarization power spectra contributions from a network of cosmic strings
We present the first calculation of the possible (local) cosmic string contribution to the cosmic microwave background polarization spectra from simulations of a string network (rather than a stochastic collection of unconnected string segments). We use field-theory simulations of the Abelian Higgs model to represent local U(1) strings, including their radiative decay and microphysics. Relative...
متن کاملSmall scale microwave background fluctuations from cosmic strings
The Cosmic Microwave Background (CMB) fluctuations at very small angular scales (less than 10) induced by matter sources are computed in a simplified way. The result corrects a previous formula appearing in the literature. The small scale power spectrum from cosmic strings is then calculated by a new analytic method. The result compares extremely well with the spectrum computed by numerical tec...
متن کاملNew CMB constraints for Abelian Higgs cosmic strings
We present cosmic microwave background (CMB) power spectra from recent numerical simulations of cosmic strings in the Abelian Higgs model and compare them to CMB power spectra measured by Planck. We obtain revised constraints on the cosmic string tension parameter Gμ. For example, in the ΛCDM model with the addition of strings and no primordial tensor perturbations, we find Gμ < 2.0×10−7 at 95%...
متن کامل