John Calarco wrote:
>Let me toss out a general question. It is really aimed at Doug, Chris,
>and Chi, but anyone can put in their 2-cents worth.
>
>At UNH, we have been discussing Adrian's ep elastic analysis vis-a-vis
>this ongoing question of momentum resolution. It suddenly dawned on me
>that we are not measuring the "intrinsic" momentum resolution (probably
>everybody else already saw this) but rather some convolution of that
>with angular resolution.
>
>What is used by Adrian as well as Chris and Chi (as far as I understand)
>is a comparison of the measured momentum with that expected from a
>kinematics calculation based on the beam energy and measured track
>angle. Thus the calculated value has a spread due to the uncertainty
>in angle, and the sigma from the Gaussian fit to the difference between
>the measured and calculated momenta then clearly is a convolution of
>the intrinsic sigma for momentum and the sigma for angular resolution.
>
>
I had an impression that we always extract the momentum resolution
from the sum of electron and
proton momenta, which is independent of the angle. It does include
momentum resolution for
both electron and proton ( or whichever dominates), but that is easy to
take into account.
Am I wrong?
Genya
>
>
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