value unc_up unc_lo author ref method 13.56 2.520 2.520 Masiero 2012ApJ...759L...8M NEATM 16.91 0.436 0.436 Masiero 2011ApJ...741...68M NEATM 17.05 0.270 0.270 Masiero 2014ApJ...791..121M NEATM