# Index of /parity/prex/accept

Acceptance Function for PREX using the Hall A spectrometers
with 5 degree Septum Magnet
Dec 5, 2011 Robert Michaels
Contents of this directory
foldedacc.dat -- (ASCII text file) --
the acceptance function \epsilon(\theta)
first column is scattering angle (degrees)
second column is the relative probability to
reach the detector
compareAccPb.gif -- plot of acceptance function and comparison
to simulation.
prex_acceptL.gif -- a picture of the acceptance. Horizontal and
vertical angles in radians. The smallest scattering
angle is on the right.
Comments on the acceptance function.
Results are averaged over two spectrometers and
have been corrected for multiple scattering.
Theoretical comparisons should use this function
to integrate over the acceptance of our spectrometers.
As an example, the average asymmetry is (latex format):
$$ A = \frac{ \int sin(\theta) d\theta A \frac{d\sigma}{d\Omega} \epsilon(\theta)}
{\int sin(\theta) d\theta \frac{d\sigma}{d\Omega} \epsilon(\theta)} $$
where $\frac{d\sigma}{d\Omega}$ is the cross section.
contact
Robert Michaels
Jefferson Lab
e-mail : rom@jlab.org