[Clas_cascades] Notes eg3 Meeting Wed June 8

[Kijun Park]

Elton Smith wrote:
> eg3 Meeting Wed June 8
> ----------------------
> Notes by Elton.
>
> Online: Mark, Hovanes, Paul, Elton, Stepan, Gordon, Maurik, Joern, Matt,
> Ralf
>
> o Alignment (Matt)
> - New DC calibrations produced by Phip and Mac. No improvement seen in the
> new alignment calibration
> http://www.jlab.org/Hall-B/secure/eg3/bellis/alignmentPlots_060805/
> - There was no visible difference between new and old alignment plots.
> Matt was asked to directly check the numbers to several decimal places to make
> sure that new calibrations were actually being used.
> - Matt mentioned that Mac believes that they can still try to improve
> the x vs. t calibration, and will check this more closely.
>
> o Cooking (Hovanes with help from Paul)
> - Preparations have started for Pass0 v2: more monitoring histograms added
> as requested at previous meetings (normalization to triggers, plots of DC
> residuals without severe cuts on tracking)
> - Paul has updated the monitoring web page
> http://www.jlab.org/Hall-B/secure/eg3/cooking/monitoring/
> The plots for v2 are somewhat different that v1, so the page needs to
> modified accordingly.
> - Changes required for v2: a) updating Maurik's modifications to root
> clas2 package b) use tagger time for RF default for status=0 (Joern)
> -> Ready to cook early next week
>
> o Skims for Pass1
> - At last cooking three skims: 1) 3neg + 1pos, 2) >1 kaon 3) >1Lambda.
> Note that this last skim had a bug that has been corrected. Also, skim #3
> selects events with a pi and proton with mass in the Lambda mass range,
> and will use the OR of seb and pid particle types.
>
> o Output banks
> - For Pass0 v2, we should probably go ahead with the same list as for v1.
> However for production Pass1, we need to be more conservative and output a
> minimum set of banks which are necessary for reconstruction. Hovanes will
> send out the list of banks used for Pass0 and will provide a suggested
> list (for comments) of banks to be output for Pass1.
>
> o CC timing (Quick update by Ralf)
> - Detailed report by Zhiwen newt week
> - Previously reported RMS values were much too large due to the inclusion
> of accidentals over a -50 to +50ns time interval.
> - After correction and use of identified electrons, peak is 2-3 ns. Very
> few statistics in each bin after requirement of Npe>5, and poor
> correllations seen for Npe<5. Therefore it is expected to be very
> difficult to get a good bin-to-bin calibration for the photon data.
>
> Next week we willl have a short meeting at the same time (2 pm).
>
> Cheers, Elton.
>
>
> Elton Smith
> Jefferson Lab
> elton at jlab.org
> (757) 269-7625
>   
Hi,
I investigated the two corrections in G11 that were issued by review 
committee. The summary is followed.
(1) 2ns tagger cut correction is about 6% for 5GeV data.
(2) Multiple Hit correction within 2ns cut is about 15% for 5GeV data.
Link page : 
http://www.jlab.org/Hall-B/secure/e1-6/parkkj/g11_analysis/report/03252010.html
I will apply these two corrections to previous cross section as final 
result.
Please let me know your any comment if you have.
Thanks.
Sincerely yours,
Kijun

-- 
---------------------------------------******
Kijun Park
Jefferson Lab.
Suit 5 Room 12_1/B107
12000 Jefferson Av.
Newport News VA 23606
Phone 757-269-6989