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The effect of color superconductivity was not consid- ered in the present work and will be the subject of a future work. 

We would like to thank the fruitful discussions with Jo˜ ao da Provid¨ı¿ 1 $_{2}$ncia, Pedro Costa and To- bias Frederico. This work was partially supported by FEDER and Projects PTDC/FP/64707/2006 and CERN/FP/83505/2008, and by COMPSTAR, an ESF Research Networking Programme. CHL thanks to CAPES by the fellowship 2071/07-0 and the interna- tional cooperation program Capes-FCT between Brazil- Portugal. 

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## Acknowledgments 

