- The various columns are the weighted average of all the available measurements, obtained as
[1] x = Sum( x_i / sigma_i ) / Sum( 1/ sigma_i )
where x_i and sigma_i are the measurements and error bars published by the individual authors.
- "sigma" refers to the total error on the average, obtained as
[2] sigma = Sqrt( Sum( sigma_i^2 / sigma_i ) / Sum(1/ sigma_i)
+ Sum( (x_i - x)^2/ sigma_i ) / (N-1) / Sum(1/ sigma_i) )
where x is the average obtained in [1]. The first term of the square
root refers to the combination of the error bars on the individual
measurements, and the second to the dispersion of the measurments.
- "disp" refers to the dispersion of the measurements, obtained as
[3] disp = Sqrt( Sum( (x_i - x)^2/ sigma_i ) / (N-1) / Sum(1/ sigma_i) )
i.e. is the second term of [2]. The "disp" of Grt is an exception;
refer to Hainaut and Delsanti 2002.
- 1998WW31+B, +C... refer to the satellites. Warning: measurements
reported for the main body (eg 1998WW31) are likely to include
measurements of the object together with its satellite(s).