value unc_up unc_lo author ref method 3.20 0.060 0.060 Masiero 2014ApJ...791..121M NEATM 3.21 0.032 0.032 Masiero 2011ApJ...741...68M NEATM 3.34 0.150 0.150 Masiero 2012ApJ...759L...8M NEATM