value unc_up unc_lo author ref method 6.66 0.270 0.270 Masiero 2012ApJ...759L...8M NEATM 7.78 0.060 0.060 Masiero 2014ApJ...791..121M NEATM 8.13 0.021 0.021 Masiero 2011ApJ...741...68M NEATM