On Thu, 4 Nov 2004, Adrian T Sindile wrote:
> Hi!
> I am a little confused by the numbers below.
> I have been looking on elog, compared with the MySQL database info etc.
>
> It looks like immediately after switching to polarized H2, runs between
> 12144 and 12187 were at a target spin angle of 20 degrees (is that right
> or just wrong epics read-back and if right why is it not mentioned
> anywhere else?)...
hall probe has not been working for a while now. The settings are
500 A + 500 A ("32 deg")
500 A + 250 A ("48 deg")
> After that, runs 12188 to 12274 are at a target spin angle of 48 degrees,
> but the total is 20 kC not 12 kC as mentioned below (maybe some of them
> were mistakingly marked as valid or the below info was not up-to-date?)...
yes I agree there was confusion. I'd like to re-iterate for the n-th time
that the pol.log and the RUNLIST file are actually important. They should
be up to date now. The charge at 48deg is indeed around 12 kC
> Anyway, most importantly, Karen's email from 4PM yesterday says we are
> running at 48 degrees and will continue like this, while all run numbers
> since 12276 (Tuesday!) up to now have a target spin angle of 32 degrees.
>
> I am just confused by the disagreement between what I see on elog and in
> these various emails... can anyone explain, please?
> Thanks you!
>
> Adrian
>
> >> We are back up to 165 mA on ABS hydrogen. The cell temperature is
> >> down a bit, now at 120 K. Beam lifetime is about 30 minutes. We have
> >> collected 30 kC on polarized hydrogen since 10/28. Almost 12 kC were at 48
> >> degrees spin angle, the rest are at 32 degrees. The target polarization is
> >> measured to be independent of spin angle. The product of beam and target
> >> polarizations is about 0.45, for a target polarization of about 67%. Chris
> >> Crawford gets about 75% with tighter cuts.
>
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