Sounds like the parameter is the monochromator angle you would need to
use to convert an unpolarised beam into a beam with the polarisation
state you have (eg, 90 degrees gives 100% polarised). Don't confuse this
with the actual monochromator angle at the synchrotron, as the bean is
usually polarised before it reaches the monochromator anyway. With some
packages you can set the monochromator "roll" angle to put the
polarisation in the right plane, depending which way up an area detector
was mounted.
Good luck,
Jon
xiu...@ualberta.ca wrote:
Hello, everyone,
I have some questions about the refinement in Topas.
When we put the instrument parameters, we always include the LP
factor, and set it to a constant value. I thought LP factor is a
function of theta and not a constant value, so my question is what
exact the constant value means. Why for unpolarized radiation, it is
equal to 0, and for synchrotron radiation it is equal to 90. Sorry to
throw so many questions.
Thank a lot for any help.
Xiujun Li
Master Student
Advanced Materials and Processing Laboratory
Chemical and Materials Engineering
University of Alberta
Edmonton, Alberta, Canada T6G 2G6
Phone: 1-780-492-0701
