[b1_ana] Neg. Tensor Pol.

[O. A. Rondon]

Hi,

I have revised my draft derivation of the asymmetry method. I think
there was some sign double counting in the first version. To avoid that,
I am now using labels, no need to keep track of signs. My notes are
posted here
http://twist.phys.virginia.edu/~or/b1/azz2.pdf

Summary: consistent with what Werner says in the message forwarded by
Dustin, and as we had already discussed at the last meeting, if I
remember right, we need negative P_zz in addition to positive P_zz.

Also, there may be a target-only Az that won't go away unless Pz = 0, or
if we can have the same sign and size Pz for both signs of Pzz.  To
check if there may be an Az, take a look at Arenhoevel's eq. (91) for
pol. d(e,e'n)p and try to see if it would be zero after integrating over
neutron angles.

Cheers,

Oscar

Dustin Keller wrote:
> Hi b1_ana,
> 
> Here is part of an e-mail that maybe of some relevance for our next
> discussion:
> 
> To measure an physics asymmetry with a vector polarized target, you need
> to measure events from a positively and negatively polarized target, as
> you certainly know. So I assume that in your case now you have to measure
> events from a positively and negatively tensor polarized target.
> Tensor polarization varies between +1 and -2.
> The vector polarized solid targets are automatically positively tensor
> polarized and the degree of the tensor polarization can be calculated from
> the measured vector polarization (assuming a Boltzman distribution among
> the 3 magnetic sublevels). However it is difficult to obtain negative 
> values for the tensor polarization in a polarized solid target and to
> measure it precisely.
> 
> Best regards
> 
> W.Meyer
> 
> _______________________________________________
> b1_ana mailing list
> b1_ana at jlab.org
> https://mailman.jlab.org/mailman/listinfo/b1_ana
>