This is actually an important point. Genya, what are your cuts ?
I asked chi to make all t20 code available and indeed much info is
at
~/pro2004/analysis/macros/Deuterium/edel/README
with a little practice you can follow the cuts almost one by one.
-- ________________________________________________________________________________ Tancredi Botto, phone: +1-617-253-9204 mobile: +1-978-490-4124 research scientist MIT/Bates, 21 Manning Av Middleton MA, 01949 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^On Fri, 23 Jul 2004, Peter Karpius wrote:
> Hi Genya- > > Are you still using beta as your sole "timing" cut? Chi has > extensive and precise timing cuts. I have found that using your cuts on the > 60cm 32 deg (post-shutdown) data I get a factor of ~1.4 more elastics than with > Chi-s cuts. Perhaps I have made a mistake though if you and Chi agree on > the number of deuterons you see. If that's the case please disregard > this! > > Pete > > > On Fri, 23 Jul 2004, Genya wrote: > > > Since there was a descripancy between the proposal and projected error > > bars (by Chi), > > I tried to do the projection separately. > > Please note, that Chi and me have somewhat different theoretical > > models and it may > > affect the projected errors, but not very much, IMO. > > Using my model, I measure Pzz of abou 80 %. In order to be > > conservative, I took Pzz=70% > > in my estimations. > > Calibrated by data from unpol runs, the target flux F=3*10**16 > > at/sec, total thickness in the > > area +- 2 cm from the center is about t=8*10**13 at/cm**2, and the > > luminosity at 100 mA is > > about 5*10**31. We expect to collect 300kC of data. > > My results with these asumptions differ drastically from Chi's: > > Chi mine > > q, f-1 T20 dT20/T20, % dT20/T20, % > > 2.28 -0.83+-.03 3.6 1.4 > > 2.66 -1.12+-.06 5.4 1.8 > > 3.10 -1.25+-.11 8.8 2.6 > > 3.62 -1.12+-.14 12.5 4.1 > > 4.20 -0.68+-.17 25.0 10.2 > > > > One can see that the difference in error bars projections is around > > factor of 3, which corresponds to almost > > factor of 10 in statistics ! > > Two additional remarks. In all our data taken after shutdown I > > observe that we don't have enough elastic events. > > In pol and unpol runs, with D2 and H2. The difference is almost factor > > of 2. Possible explanations: > > a) another hole in the cell > > b) inefficiency in detection/tracking/cuts. > > c) I've made a mistake somewhere. > > At least point c) must be checked by someone other than me (Chi?) > > And we need to sit with Chi and work out our differencies in error > > bars projection. > > > > Genya > > > > > > ---------------------------------------------- > Pete Karpius > Graduate Research Assistant > Nuclear Physics Group > University of New Hampshire > phone: (603)862-1220 > FAX: (603)862-2998 > email: karpiusp@einstein.unh.edu > http://pubpages.unh.edu/~pkarpius/homepage.htm > ---------------------------------------------- >
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