http://arxiv.org/abs/1312.6106
It was received observational limits about the number of cosmic strings (Nambu-Goto, Abelian-Higgs, semilocal) and other topological defects (textures). Radio maps of CMB anisotropy, collected by space mission “Planck” for various frequencies were filtered, and then were processed by the method of convolution with modified Haar functions (MHF) to search for cosmic string candidates. This method was intended for search of solitary strings without additional assumptions about the presence of networks of such objects. The sensitivity of the MHF method is $\delta T \approx 10 \mu K$ in background of $\delta T \approx 100 \mu K$. We compared these results with previously known ones on search string network. The comparison shows that strings can only be semilocal in amount of $1 \div 6$ with the upper restriction on individual strings tension (linear density) of $G\mu/c^2 \le 7.36 \cdot 10^{-7}$. The texture model is also legal. There are no strings with $G\mu/c^2 > 7.36 \cdot 10^{-7}$. However, comparisons with the data for the search of non-Gaussian signals shown, that the presence of several (up to 3) of Nambu-Goto strings is also possible. For $G\mu/c^2 \le 4.83 \cdot 10^{-7}$ the MHF method is ineffective because of unverifiable spurious string candidates. Thus it is not forbidden the existence of string with tensions $G\mu/c^2 \le 4.83 \cdot 10^{-7}$ but it is beyond the “Planck” data scope.
Mon, 23 Dec 13
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