QuasiLocalMeasures qlm_spin doesn't work for spins not aligned along the z axis
Einstein Toolkit version: ET_2018_02
.
Parameter file: qc0-mclachlan.par
in einsteinexamples with the additional parameter TwoPunctures::par_S_plus [0] = +0.3
Problem: The diagnostic qlm_spin[0]
returns a spin of 0, whereas the expected one should be 0.3.
If instead of TwoPunctures::par_S_plus [1] = +0.3
one sets
TwoPunctures::par_S_plus [2] = +0.3
, qlm_spin[0]
is correctly
outputting 0.3
This happens because QuasiLocalMeasures finds in both cases the rotational Killing vector d/dphi (as seen setting QuasiLocalMeasures::veryverbose = yes
), which is correct in the second case (when the axis aligned with the z-direction), but doesn't sound right when the rotation is with respect to the x-axis.
Changing QuasiLocalMeasures::killing_vector_method
to axial
or gradient
does not change the outcome.
Best regards, Gabriele
Keyword: QuasiLocalMeasures