Vitaliy,
I agree. Let's keep up the effort to sort it out but also let's keep
data taking until we have definitive conclusions.
Richard
On Mon, 15 Mar 2004, vitaliy ziskin wrote:
> May I suggest not rushing into changing to long. target. Maybe, first
> we need to understand what is going on. First of all, spin counting can
> not be a suspect here because it is done the same way for both sectors
> and for vector asymmetry. I agree with Chi, that we have a problem with
> reconstruction rather than target or bit counting. What is our signal
> to noise ration in both sectors? How well do we see elastic peak? How
> well do we reconstruct momentum? I think that all these things need to
> be addressed before we change setup.
>
> Chi Zhang wrote:
>
> >Hi Richard,
> >
> >My problem with electron into right sector is consistant with Genya's. But
> >in constradict with Vitaliy's, which is better in LEFT electron. I don't
> >know any details about Genya's analysis so I don't know to what extend he
> >recovers the elastic cross section.
> >
> >I feel a little uneasy that analysis in ep elastic and other D2 channels.
> >so I hope Genya had better cross section results.
> >
> >Just a follow up, please again see the attached dpe.ps. It draws (electron
> >momentum reconstructed - electron momentum calculated from electron
> >scattering angle). The sigma of the peaks are <=40MeV which is consistant
> >with what we see with ep elastic. However, there is slight different in
> >the position of the two peaks. on lower 30MeV than 0, one 20MeV higher.
> >Tancredi pointed out to me that this is in fact a big left right
> >inconsistancy, much bigger than the error in determination of the peak
> >positions. again, red is electrons into the right.
> >
> >So it maybe is not a big suprise that we have inconsistant results in left
> >and right sectors. Just it is our bad luck the poor results appear in the
> >sector we expect to see the larger asymmetry.
> >
> >Chi
> >
> >On Mon, 15 Mar 2004, Richard Milner wrote:
> >
> >
> >
> >>Hi Chi,
> >>Thanks for the message. Is your conclusion (electron right problematic)
> >>consistent with Genya and Vitaly? I think your statement about the cross
> >>section is very relevant. As we know, to form reliable asymmetries the
> >>rates should be statistical. Is the spin sorting for left and right
> >>detectors common or separate?
> >>Richard
> >>
> >>
> >>
> >
>
>
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