value unc_up unc_lo author ref method 6.51 0.090 0.090 Masiero 2014ApJ...791..121M NEATM 6.67 0.058 0.058 Masiero 2011ApJ...741...68M NEATM 7.17 1.520 1.520 Masiero 2012ApJ...759L...8M NEATM