Global VLBI EOPI Solution 2008a
USNO Global VLBI Intensive Solution 2008aFebruary 2008

Presented here is the U.S. Naval Observatory's i2008a analysis of 1.5 hr dualfrequency VLBI sessions carried out under the auspices of the International VLBI Service (IVS) Intensive Program. UT1 angles are determined for most sessions between 2000 July 06 and 2008 February 18 using dualfrequency observations obtained at 8.4 GHz (Xband) and 2.2 GHz (Sband).
The SOLVE batch control file int2008a.cnt was used to generate a leastsquares solution with an output spool file int2008a.spl.gz. Note that this solution uses Calc10 (see calc10.ps). Tabulated below are the session values from this solution.
Earth Orientation Parameters
UT1 angle is determined for each session separately.
EOP time series, Solve format  int2008a.eop  format description 
EOP time series, EOB format  int2008a.eob  format description 
EOP time series, IVS format  int2008a.eopi  format description 
Comparisons
Differences of the i2008a UT1 angles with the IERS 05 C 04 UT1 angles.
Plot of i2008a minus IERS 05 C04  PS  JPG 
Linear Regression: bias = 4.1 +/ 0.5 microseconds at J2000 Linear Regression: rate = 1.4 +/ 0.2 nanoseconds/day Residuals: w.r.m.s. = 14.1 microseconds Residuals: chi2/ndg = 2.77
Differences of the i2008a UT1 angles with the GSFC int22 UT1 angles.
Plot of i2008a minus gsfint22  PS  JPG 
Linear Regression: bias = 0.3 +/ 0.8 microseconds at J2000 Linear Regression: rate = 0.4 +/ 0.4 nanoseconds/day Residuals: w.r.m.s. = 7.3 microseconds Residuals: chi2/ndg = 0.33
Differences of the i2008a UT1 angles with the i2007c UT1 angles.
Plot of i2008a minus i2007c  PS  JPG 
Linear Regression: bias = 0.4 +/ 0.7 microseconds at J2000 Linear Regression: rate = 0.1 +/ 0.3 nanoseconds/day Residuals: w.r.m.s. = 3.9 microseconds Residuals: chi2/ndg = 0.10