value unc_up unc_lo author ref method 7.69 0.220 0.220 Masiero 2012ApJ...759L...8M NEATM 8.07 0.150 0.150 Masiero 2014ApJ...791..121M NEATM 8.18 0.043 0.043 Masiero 2011ApJ...741...68M NEATM