[G12] resolution of tagger in kinematic fitter

[Eugene Pasyuk]

Lei, Carlos explained it correctly. It should be electron beam energy, which is a constant. 

-Eugene 

> From: "Lei Guo" <lguo at jlab.org>
> To: "Carlos Salgado" <salgado at jlab.org>
> Cc: "g12 at jlab.org g12 at jlab.org" <g12 at jlab.org>
> Sent: Wednesday, February 10, 2016 2:49:16 PM
> Subject: Re: [G12] resolution of tagger in kinematic fitter

> That’s fine except the E_beam here should be the Energy of the photon, instead
> the constant (of the electron beam energy) that’s now used in the code. Did I
> get that wrong?

> Lei

> Lei Guo
> Assistant Professor
> Physics Department
> Florida International University
> Miami, FL

> email: leguo at fiu.edu or lguo at jlab.org
> Office:305-348-0234

>> On Feb 10, 2016, at 12:39 PM, Carlos Salgado < salgado at jlab.org > wrote:

>> Hi

>> Follow the discussion in last g12 meeting.

>> The formula in the code for the variance of the photon bean energy is OK.

>> The uncertainty in the energy of the photon is 0.001* E_beam (per NIM and Eugene
>> P.) The hodos were built such that this is true (different widths)

>> Then consider a counter of width (energy) "a" where the (assume) energy
>> distribution is flat: then Variance = sigma^2 = 1/a* int^a_0 E^2 dE = a^2/3

>> Therefore if we distribute the uncertainty over a counter (energy bin) the
>> variance is : sigma^2 = (0.001*E_beam)**2/3

>> =Carlos
>> _______________________________________________
>> G12 mailing list
>> G12 at jlab.org
>> https://mailman.jlab.org/mailman/listinfo/g12

> _______________________________________________
> G12 mailing list
> G12 at jlab.org
> https://mailman.jlab.org/mailman/listinfo/g12
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/g12/attachments/20160210/2d5758ea/attachment.html>