%0 Conference Paper
%A Vogel, Hendrik
%A Redondo, Javier
%T Dark Radiation from a hidden U(1)
%C Hamburg
%I Verlag Deutsches Elektronen-Synchrotron
%M PUBDB-2016-05939
%@ 978-3-935702-59-1
%B DESY-PROC
%P 196-199
%D 2014
%< Vogel, Hendrik "Dark Radiation from a hidden U(1)" in Proceedings, 10th Patras Workshop on Axions, WIMPs and WISPs (AXION-WIMP 2014)  / Tsesmelis, Emmanuel, Maroudas, Marios (eds.), Verlag Deutsches Elektronen-Synchrotron : 2014 ; AXION-WIMP 2014 : 10th Patras Workshop on Axions, WIMPs and WISPs, 2014-06-29 - 2014-07-04, Geneva
%X We discuss the impact of a hidden sector consisting of Minicharged Particles (MCPs) and massless hidden photons on the expansion history of our Universe. We present parameter scans for the amount of extra relativistic particles (N<sub>\texteff</sub>) and the abundance of light nuclei for fermionic MCPs with masses between  ∼ 100 keV and 10 GeV and minicharges in the range 10<sup>−11</sup>−1. Current CMB and BBN data significantly constrain the available parameter space of MCPs. The shown results are a valuable indicator for future experimental searches and are presented in a flexible way so that more accurate results on N<sub>eff</sub> can be easily interpreted.
%B 10th Patras Workshop on Axions, WIMPs and WISPs
%C 29 Jun 2014 - 4 Jul 2014, Geneva (Switzerland)
Y2 29 Jun 2014 - 4 Jul 2014
M2 Geneva, Switzerland
%F PUB:(DE-HGF)8 ; PUB:(DE-HGF)7
%9 Contribution to a conference proceedingsContribution to a book
%R 10.3204/DESY-PROC-2014-03/vogel_hendrik
%U https://bib-pubdb1.desy.de/record/315532