English

Observational constraints on the types of cosmic strings

Cosmology and Nongalactic Astrophysics 2014-07-29 v2 High Energy Astrophysical Phenomena

Abstract

This paper is aimed at setting observational limits to the number of cosmic strings (Nambu-Goto, Abelian-Higgs, semilocal) and other topological defects (textures). Radio maps of CMB anisotropy, provided by the space mission Planck for various frequencies, were filtered and then processed by the method of convolution with modified Haar functions (MHF) to search for cosmic string candidates. This method was designed to search for solitary strings, without additional assumptions about the presence of networks of such objects. The sensitivity of the MHF method is δT10μK\delta T \approx 10 \mu K in a background of δT100μK\delta T \approx 100 \mu K. The comparison of these with previously known results on search string network shows that strings can only be semilocal in an amount of 1÷51 \div 5, with the upper restriction on individual strings tension (linear density) of Gμ/c27.36107G\mu/c^2 \le 7.36 \cdot 10^{-7}. The texture model is also legal. There are no strings with Gμ/c2>7.36107G\mu/c^2 > 7.36 \cdot 10^{-7}. However, comparison with the data for the search of non-Gaussian signals shows that the presence of several (up to 3) of Nambu-Goto strings is also possible. For Gμ/c24.83107G\mu/c^2 \le 4.83 \cdot 10^{-7} the MHF method is ineffective because of unverifiable spurious string candidates. Thus the existence of strings with tensions Gμ/c24.83107G\mu/c^2 \le 4.83 \cdot 10^{-7} is not prohibited but it is beyond the Planck data possibilities.

Keywords

Cite

@article{arxiv.1312.6106,
  title  = {Observational constraints on the types of cosmic strings},
  author = {Olga S. Sazhina and Diana Scognamiglio and Mikhail V. Sazhin},
  journal= {arXiv preprint arXiv:1312.6106},
  year   = {2014}
}

Comments

15 pages, 10 figures; accepted by the European Physical Journal C