Operator: ajmasch
continued taking polarized deuterium data. wc box r24 has been tripping about every five minutes for the past six or so hours. i lowered it to 3800V, which didn't seem to have much immediate effect. however, within the past hour, it has quieted down.
maybe there is a simple reason for this, but why do the abs and blast alarm handlers overwhelmingly seem to go off in unison? i see that the blast alarm has an abs button on it, so it makes sense that they go off in unison when there is an abs alarm. however, mostly, it seemed that it was a hv trip that caused the unison alarms. quite annoying...
i took a look at the 32deg polarized deuterium data. i now have a 32deg monte carlo file to compare with (though it is still lacking in that it doesn't yet take spin variation along z into account). anyway, using nearly all the 32deg data (about 38kC worth), i get the following from fitting the beam vector asymmetry versus Q^2:
dilution left : 0.37 +- 0.018
dilution right : 0.39 +- 0.016
assuming a beam helicty of 61.2% (according to the latest compton readings), this gives a target polarization of about 62%.
using a (semi) independent analysis of the asymmetries versus missing momentum, i get the following dilutions:
dilution left : 0.33 +- 0.017
dilution right : 0.32 +- 0.014
to get these results, i fitted the asymmetries up to a missing momentum of 0.2GeV and ignored anything higher. this missing momentum region has an essentially flat asymmetry that all models agree on. i could, perhaps, go a little higher without introducing significant model variation errors.
i still need to play with the cuts a little. also, i haven't taken background into account yet (though, despite initial esitmates given last week, it now appears that the 60cm background is comparable to the 40cm's). also, as previously mentionned, spin variation along z hasn't been accounted for.
my tensor polarizations are:
polarization left : 0.24 +- 0.061
polarization right : 0.42 +- 0.093
This archive was generated by hypermail 2.1.2 : Mon Feb 24 2014 - 14:07:31 EST