HI Elton,
I have obtained the resolution VS the beam position in a rough way,
namely I took the entry position
instead of the energy-weighted average position (EWAP) for each cell
separately (just in order to speed up the
procedure, but later I'll redo it with the EWAP).
Please find the results on the web site
http://www.jlab.org/~rafael/Beamtest/
cleaking on the last link, i.e. "Energy Resolution VS the Beam Position".
Let me inform you, briefly, that the distribution of the deposited
energy in the scintillating fibers is obtained
for the cases when the incident photons with the energy of 500 MeV and
spot size of 18.7mm (2.6mm collimated beam) are entring the BCAL
perpedicularly from different positions ( 0 cm(centre), 0.5cm, .....).
The fitted sigmas are for the distributions of the average energy at
the both ends after the attenuation (atten. length is 3m).
Details we can discuss tomorrow at the teleconference.
Best regards,
Rafael
Elton Smith wrote:
HI Rafael,
Thanks for the addition. It looks like the curve has a slope even at the
center, perhaps implying that we in fact do have sensitivity even to the
smallest change in the the beam position. However the amount of leakage is
very small, so I assume that the resolution is not much affected. Do you
have a plot of the resolution as a function of the beam position?
Cheers, Elton.
Elton Smith
Jefferson Lab
elton@jlab.org
(757) 269-7625
On Tue, 18 Jul 2006, Rafael Hakobyan wrote:
Hi Elton,
In the plots that have been presented today, I have added the points
corresponding to the percentage of the energy leakage (WRT the incident
photon energy) when the photon beam enters the BCAL from the centre.
Please find the improved plots on the web site
http://www.jlab.org/~rafael/Beamtest/misalignment/
Thanks for the relevant comment.
Rafael
Rafael Hakobyan wrote:
Hi All,
Please find some more simulation results on the web site
http://www.jlab.org/~rafael/Beamtest/
Two more links are added, namely
a). shower energy leakage from the BCal module when the beam is
misaligned
from the BCal centre
b). distribution of the Up and Down time difference for the
collimated (2.6mm)
beam and for the pencil beam
about which Zisis and I want to discuss with you during today's
teleconference.
Time always has been calculated in two ways: taking the energy
weighted time and the very first
photon time. Our investigations always show that the sigma is smaller
for the energy weighted
time. From the beging for the calculation of the time, I have had very
useful and productive discussions
with Richard Jones about the energy weighted time, and I want to
express my thankfulness to Richard for the useful discussions.
Cheers,
Rafael
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