value unc_up unc_lo author ref method 6.31 0.200 0.200 Masiero 2011ApJ...741...68M NEATM 6.67 0.200 0.200 Masiero 2012ApJ...759L...8M NEATM 6.97 0.204 0.204 Masiero 2011ApJ...741...68M NEATM