value unc_up unc_lo author ref method 6.43 0.140 0.140 Masiero 2014ApJ...791..121M NEATM 6.73 0.038 0.038 Masiero 2011ApJ...741...68M NEATM 7.27 0.420 0.420 Masiero 2012ApJ...759L...8M NEATM