Abstract
We study signatures of cosmic superstring networks containing strings of multiple tensions and junctions, on the cosmic microwave background (CMB) temperature and polarization spectra. Focusing on the crucial role of the string coupling constant , we show that the number density and energy density of the scaling network are dominated by different types of string in the and limits. This can lead to an observable shift in the position of the -mode peak—a distinct signal leading to a direct constraint on . We forecast the joint bounds on and the fundamental string tension from upcoming and future CMB polarization experiments, as well as the signal to noise in detecting the difference between -mode signals in the limiting cases of large and small . We show that such a detectable shift is within reach of planned experiments.
- Received 31 May 2011
DOI:https://doi.org/10.1103/PhysRevLett.107.121301
© 2011 American Physical Society