[Halld-jlab] FOM for solenoidal field

[Elton Smith]

Dear collaborators,

I was encouraged to summarize the figure-of-merit (FOM) and the argument
for using this quantity as a justification for running the solenoid at
1500A.

I have placed my argument and the FOM plot on the wiki at
http://www.jlab.org/Hall-D/software/wiki/index.php/Experimental_Sensitivity_to_Solenoidal_Field

>From the outset I realize that this quantity may not be the most relevant
for all physics channels.  It will depend on what limits the experimental
measurement. The proposed FOM makes the assumption that the luminosity is
limited by the electromagnetic background.  There are in fact indication
are that the rates in the detectors are close to their operational limits,
so this is not an unreasonable assumption. Other limitations might
include, for example, the accidentals in the tagger, which would lead to a
different FOM.

In any case, comments and feedback to this FOM are welcome, and the wiki
page can be used to collect and summarize our thoughts on this subject.

Cheers, Elton.



Elton Smith
Jefferson Lab MS 12H5
12000 Jefferson Ave
Suite # 16
Newport News, VA 23606
elton at jlab.org
(757) 269-7625
(757) 269-6331 fax