Minutes Apr2012 to Dec2012

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Revision as of 16:26, 8 January 2013 by Jixie (Talk | contribs) (New page: ---- ==12/18/2012== Present: Jixie, Vince, Jie, Min, Melissa <br> By-Phone: Ryan, Toby, Pengjia <br> '''General discussion''' NO meetings for the following 2 weeks. '''Feature prese...)

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12/18/2012

Present: Jixie, Vince, Jie, Min, Melissa
By-Phone: Ryan, Toby, Pengjia

General discussion

NO meetings for the following 2 weeks.

Feature presentation:

  • Pengjia:
    • Present the status of the BPM calibration. There are some updates in the software package.
    • Pengjia need to use the distribution average of the position at BPM A and B to calculate the

position at target, not the instant measurement values. See the details here

  • Toby:
    • New version of analyzer is released. Trying to switch to the new version.
    • Testing the replay scripts after including the BPM packages.
    • Waiting for calibration constants from other students.
  • Ryan:
    • Moving back to do optics optimization for RHRS, 5T longitudinal field data set.
  • Jixie:
    • Dave Meekins have a very nice figure about the g2p target. Click here to view it.
    • Got the C12 foil target holder drawing from Josh. This drawing shows that the C12 foil has a

extra holder of 50 mil thick. It also indicates that the C12 foil is located at the upstream end cap
location, not the insert! (It was designed to be at the insert.) Optics and simulation need to take this into account.

  • Jie:
    • Present the status of the study to the pion rejector's efficiency. Check details here.
    • Melissa and Jie will work out a calibration constant set and send to Toby.
  • Min:
    • Verifying the optimizer is really taking the survey parameters.
    • Will run it again once beam position are ready. Then do Ytg calibration.

12/04/2012

Present: Jixie, Vince, Chao, Jie, Min, Kalyan, Karl, Melissa
By-Phone: Ryan, Toby, Pengjia

General discussion

  • Dry run talks for the Hall A calibration will be held 1 PM Wednesday. Vince will

reserve a room.

Feature presentation:

  • Min:
    • Tried to understand the discrepancy between the spectrometer in SNAKE model and the

real spectrometer. Generated a new no-raster SNAKE model with the same quadruples setting as
real experiment. See details here.

  • Chao:
    • Studied the discrepancy between simulation and real data. See the talk here.
      • The optimized database was optimized from a narrow distribution of theta and phi, which

might not work well for area beyond the optimized area. Chao recreated the plot of 9 spots where
all spots are within the optimized area. The discrepancy is smaller but still noticeable.

      • Tried to use Min's latest no raster snake model to create the 9-spot-plot. (Jixie, Min and Chao also

tried several other snake models.) It turns out that 1) the raster is not the reason and
2) all SNAKE models have this discrepancy.

      • Per Vince's suggestion, a comparison of the reconstruction from real focal plane data to the

target plane was made between SNAKE backward model and real optics database.

  • Jixie:
    • Present the study of mapping for 5T target field. See the slices here.
      • Jixie studied mapping on focal plane with 4-D grid (x-theta-y-phi) with the bin width of 5mm-5mr-5mm-5mr

and also with a smaller grid 2mm-2mr-2mm-2mr. It turns out that no matter how small the grid is, the width
of the theta,phi distribution in target plane are very wide. If considering he CPU time it cost to run simulation, 5-5-5-5 binning is practicable.

      • Studied the mapping in the sieve plane (need to use straight through reconstruction to reconstruct to the

target plane then project to sieve). Tried 2 binning: 2mm-2mr-2mm-2mr and 1mm-1mr-1mm-1mr. When decrease the
grid size, z,y,phi distribution in the target plane become narrower but no the theta distribution. The CPU time
cost for 2-2-2-2 is acceptable.

      • Need to weight by world XS database to determine the mean value for a given unweighted distribution.
  • Melissa:
    • Presented the study of the cut efficiency of the Cherenkov and lead glass in L-HRS. See details here.


11/27/2012

Present: Jixie, Vince, Chao, JP, Jie, Min, Kalyan, Karl, Alex, Melissa
By-Phone: Ryan, Toby, Pengjia

General discussion

  • Decided to finish the pass1 calibration by the end of this year. All units should provide necessary information

to Toby before Christmas. Toby is expected to cook the data by early January.

  • Optics need more man power. Ryan will conduct longitudinal optics soon and Chao will dedicate in running simulation

to speed up the optics work.

Feature presentation:

  • Toby:
    • Working on target analysis scripts. Almost finish the analysis using baseline subtraction method.

Toby agreed to show the comparison of his result with online result.
James did some target calibrations before. Karl will follow up with James to find out how much had been done
and what can be used. Dustin is also doing some study with the g2p targets. He agrees to provide technical notes.

  • Ryan:
    • Dead time and scintillator (trigger) efficiency have been added into the mysql database.
    • Will working on the annual report. After that will go back to take over the longitudinal optics from Chao.
  • Pengjia:
    • Had a brief update on the BPM status. Pengjia plan to follow Jixie's suggestion and produce ascii table for each

run. Later on this table will be inserted to the replay output right after replay finished. There are some concerns
from JP that such a separate BPM package are difficult to maintain. The best way, of course, is to put the BPM package
back into replay, which requires extra work from Pengjia since this BPM package is written with python.
See Pengjia's report here.

  • Jie:
    • Updated the pion rejecter calibration. This time Jie only use P0>1.2 GeV/c data to extract the calibration constant,

which provide a consistent result between 5T and 2.5 data set. Jie also studied the Cherenkov cut efficiency. See details here

  • kalyan:
    • Summarized the analysis status. See details here.

11/20/2012

Present: Jixie, Vince, Chao, JP, Jie, Min, Kalyan, Karl
By-Phone: Ryan, Toby, Pengjia

Feature presentation:

  • Pengjia:
    • BPM calibration for NONE target field data is ready to use. Python codes to calculate beam positions

and merge them into the ntuple are ready. Please refer to Pengjia's talk for instruction.

    • Toby agreed to modify the job scripts to run BPM calibration after replaying.
  • Chao:
    • Added real-reconstruction module into Geant4 simulation program, HRSMC. This module can reconstruct focal

plane hits back to target plane using the optics database optimized from the experimental optics data. This module
will help a lot in comparing simulated data with real experimental data.

    • Chao present some figures about the comparison of the reconstructed result from snake model with that

reconstructed from database. Currently they do not agree with each other. We have no idea which one is correct.
Need to find out. See his talk here.

  • Min:
    • Created 400016 L-HRS no target field snake model. This model have been included into HRSMC.
    • Did the first trial to optimized Ytg reconstruction using the built BPM in the ntuple. These BPM information

are totally unreliable. Min agreed to put nominal beam positions or Pengjia's calibrated values and try again.
See details here.


11/13/2012

Present: Jixie, Vince, Chao, Melissa, Jie, Min
By-Phone: Ryan, Toby, Pengjia

Feature presentation:

  • Ryan:
    • present the updates in trigger efficiency, see details here.
  • Toby:
    • Updated the target analysis results in the wiki.
    • Writing the script to apply the calibration constant to each run.
  • Jie:
    • Cross checked the preshower|shower calibration. Verified that the discrepancy are due to the target

field. But Jie's result still have this discrepancy in his calibration. There is still some room to improve.

11/06/2012

Present: Jixie, Vince, Alex, Chao, Melissa, Jie, Kalyan, JP, Min, Karl
By-Phone: Ryan, Toby, Pengjia

Feature presentation:

In this trial Pengjia use Minuit to fit for the calibration constants a,b,c.

  • Chao:
    • Presented the optics optimization result for 5T Longitudinal field for L-HRS. At this version Chao select

only the ground state C12 elastic events for each hole. Hole #65 and #46 are exclude since their dP distribution
look weird. Will include these 2 holes at the 2nd iteration.

    • Ytg optimization is not done yet. Will try to do it use Pengjia's current calibration result.
  • Min:
    • Created SNAKE model for left HRS with 5T longitudinal target field and 400016 septum.
    • Presented the straight through optics result for Right HRS.
    • Will try Ytg calibration later.

Melissa showed that tr.y distribution have some obvious difference for 2.5T and 5T target fields, which indicate
that the target field is the reason cause the discrepancy in Edep/P0 between 2.5T data set and 5T data set.
Melissa adjust the calibration for the 5T data set. The result looks good. After calibration, the energy resolution
of the pion rejector can reach 20% for 0.5 GeV electron, or 7% for 1 GeV electron, or 3% for 2 GeV electron.

10/30/2012

Present: Jixie, Alex, Chao, Melissa, Jie, Kalyan, JP, Min
By-Phone: Ryan, Toby, Pengjia

Feature Presentations:

  • Toby:
    • Updated on TE calibrations analysis. Need to understand fluctuations in TE calibration constants(sometimes ~10-20%)
    • Trying to figure out how to combine different constants for a given sample ( take average, for eg.)
  • Jie:
    • Showed 2.2 GeV RHRS calibration for the shower+preshower.
    • There is difference in E/p value for same momentum taken at different target fields(2.5 T vs 5T).
    • trying to understand where the difference is coming from. Need to look at a no field run to understand the acceptance
  • Pengjia :
    • Still working on BPM calibration. Will present a more detailed report next week.

10/23/2012

Present: Karl, Jixie, Alex, Chao, Melissa, Jie, Kalyan, JP
By-Phone: Ryan, Toby, Pengjia, Min


General Discussion:


Feature Presentations:

  • Melissa:
    • Updated the preshower|shower calibrationfor LHRS. Saw the same discrepancy between the 2.5T

target field data set and the 5T dta set. She tried 3 methods but none will remove the
discrepancy. See details here.

Chao selected clean sieve hole events with cuts on Y_tg, Phi_tg, Theta_tg and dP. The optimized result
looks OK, but still has rooms to be improved. This data set might have issues of aligning some sieve
spots into a wrong hole.

    • Some suggestions were given to Chao:
  1. Select very clean sieve data: only ground state elastic data, remove confusing areas
  2. Try to identify the sieve hole for each spot to avoid signing to a wrong hole
  3. Simulation could help

which is similar to what Chao was using, but exclude the excited state elastic events from each hole.

    • The result looks OK.

10/16/2012

Present: Karl, Jixie, Alex, Min, Melissa, Jie, Kalyan, JP
By-Phone: Ryan, Toby, Pengjia, Chao

General Discussion:
 Next Hall A collaboration meeting will be held in Dec 10 to Dec 12. G2p will give
three presentations. Melissa will present general physics topic, Jixie will present
the simulation of G2p in the analysis workshop, Min will also give a talk about the
optics from real data.


Feature Presentations:

  • Ryan:
    • Working on trigger efficiency, see details here
  • Toby:
    • Working on target analysis. Applying the standard method through all TEs.
    • Writing scrips to extract the calibration constants and apply them in the analysis.

Toby will also compare the results to the online results from James.

Pengjia pick 3 calibration points from the samples (5-7 points for each setting) to calculate
constant a,b and c. Then he compared the BPM pattern from one group to another.

    • Will try to use TMinuit to fit all data points for a, b and c. Jp suggested adding a weighting

factor to each data point. How to weight the data point is not clear yet. Need to find out.

  • Jie:
    • Updated the LHRS pion rejector calibration. See details here.
  • Jixie:
    • Show updates of the optics reconstruction in simulation.
      • A new snake model with 3cm raster size available, Y_tg resolution has been improved a lot.
      • Applied correction to get effective BPM vertical position when target field is on.
      • Applied energy loss correction
      • The reconstruction strategy proposed by Jixie has to face the fact that vertex Z have large

uncertainty. Need to find out a cut to select data within 10 mm from the target end plane in
order to keep the uncertainty of the scattering angle below 1.5 mrad, which is required to
achieve 5% uncertainty in the absolute cross section.

10/9/2012

Present: Karl, Vince, Alex, Chao, Min, Melissa, Jie, Kalyan, JP
By-Phone: Ryan, Toby, Pengjia

General Discussion:
 See agenda for talks

Feature Presentations:

  • Melissa Cummings:
    • Working on the LHRS lead-glass calibration
    • Currently looking at 1 pass data calibration(see agenda for the talk)
    • First round calibration gives 7% resolution for E0=2.2 GeV and p0=1.0GeV/c
  • Chao Gu:
    • Updated on optimization of longitudinal optics runs using 2.2 GeV sieve data
  • Min Huang:
    • Updated on straight through optics for LHRS (good septum condition)
    • Used different order for matrix, used react z cuts (maynot be right variable to cut, will try tgt_y)

10/2/2012

Present: Vince, Alex, Pengjia, Chao, Min, Melissa, Jie, Kalyan, Jixie,
By-Phone: Karl, Ryan, Toby, Pengjia

General Discussion:


Feature Presentations:

  • Toby:

1) Toby did target analysis with baseline subtraction method, the standard method
James and others are using. His results agree with the on-line results from James.
He has finished 4 TEs, 55 TEs to go.

  • Ryan:

1) Learning and preparing to calibrate S1 and S2, will do trigger efficiency then.

  • Pengjia:

1) Present the status of BPM calibration. Pengjia tried to make the distorted pattern of BPM
look more like a circle. So for no improvement yet. The calibration constant A, B and C were
calculated with 3 calibration points. 2 suggestions were given to Pengjia:
A) Use Minuit to fit A,B and C since there are 7 calibration points
B) Look at a small region that are covered by calibration points to check if its pattern looks
like a circle.

  • Jie:

1) LHRS pion rejector calibration. See details here.

09/25/2012

Present: Vince, JP, Alex, Pengjia, Chao, Min, Melissa, Jie, Kalyan, Jixie, Karl
By-Phone: Ryan, Toby, Pengjia

General Discussion:

Data analysis status and plan:

We almost reach our initial goal to finish detector calibration by the end of fall.
Run database is ready. VDC, Cherenkov calibration are finished, BCM, lead glass
calibrations are very near to the end. Target field measurement analysis, helicity
decoding are also finished. The target polarimetry analysis, straight through optics
optimization and BPM calibration are in progress. However, the calibration for scintillators
S1 and S2 have not been started. Optics for other data sets have not been touched yet.

Optics optimization will dominate the time scale. In this meeting, we decided to let Ryan
to finish the S1 and S2 calibrations first, then join back to optics group to cross check
the result. At the same time, Min and Chao will work together to do the optimization, one
for the no target field data set and the other for longitudinal target field data set.


Feature Presentations:

  • Melissa:

1) Melissa gave updates on the preshower/shower calibration.
She applied tighter cuts to selectron electron, and looked into Etot/P distribution,
checked the stability of the calibration constants and showed a plot of the momentum resolution
provided by the preshower/shower detector.

  • Min:

1) Min presented her latest optimization result for LHRS straight through Optics.
She choose 100 events from each hole, increased the order of some variables when fitting
the tensor for Theta_tg. These changes improve the result a lot, but there are still two holes
closed to the beam line does not line up to the expected position. She will keep working on it.

  • Jixie:

1) Presented the event reconstruction in the simulation.

  • Chao:

1) Presented how the uncertainty propagated when convert theta_tr, phi_tr in transport
coordinate system into lab coordinate system. See details here.

  • Kalyan:

1) Showed the analysis flow chart.

09/18/2012

Present: Vince, JP, Alex, Pengjia, Chao, Min, Melissa, Jie, Kalyan, Jixie, Karl
By-Phone: Ryan, Toby, Pengjia

General Discussion:

Feature Presentation:

  • Jie:

1) Preshower|shower calibration, see details here.

  • Toby:

1) Update on the status of target analysis. Toby is trying to a new method to do this analysis. see details here.

  • Ryan:

1) Cross check optics optimization.

  • Jixie:

1) Show event reconstruction in simulation. Resolution of reconstructed x,y,theta,phi for both with and without
target field have been shown. Check plots [1].

09/12/2012

Present: Vince, JP, Alex, Pengjia, Chao, Min, Melissa, Jie, Kalyan, Jixie
By-Phone: Karl, Ryan, Toby

General Discussion:

In order to have Pengjia join this analysis meeting from China, we plan to move this
meeting to Tuesday 11:00-13:00. Vince will reserve a room.

The meeting will be organized in a way that each week there will be 3 presentations
from 3 students. This week Melissa, Min and Chao will give presentations. So do Ryan,
Toby and Jie next week. Those who make presentations should update the agenda page before
the meeting. Will repeat this pattern every 2 weeks.

Feature Presentation:

  • Melissa:

1) Showed the preliminary result for the right HRS pre-shower|shower calibration.
2) The low momentum setting for each beam energy need to recalibrate. Melissa agrees to do that

  • Min:

1) Optics optimization result with the following improvement:
A) no more than 1000 events each hole
B) Sample includes dp= +/-3%, +/-2% and 0%, +/-4% not included
C) Survey result applied
See details here.

2) Plot shown that data on the top edge are not calibrated well. Min will try to optimize
it again with only 100 events from each hole. In order to have more statistics on the edge,
she might need to include dp=-4% data into the sample.

  • Chao:

1) Put the target field measurement result onto the wiki: check here for details.
2) Final report can be found here.
This field measurement was believed to reach 1% uncertainty.


09/05/2012

Present: Vince, JP, Alex, Pengjia, Chao, Min, Melissa, Jie, Kalyan, Jixie
By-Phone: Ryan, Toby

General Discussion:

Pengjia is leaving in Sep. 13. We are going to have a cake party for him next week.

In order to have Pengjia join this analysis meeting from China, we plan to move this
meeting to the morning (9:00-11:00 or 10:00-12:00). Vince will find out the time and
meeting room.

Feature Presentation:

  • Pengjia:

1) BPM calibration status update
Pengjia compared 4 methods to reconstruct beam position.

  • Melissa:

1) Melissa found some strange behavior of the RHRS VDC distributions. There are 4 peaks on NH3 elastic
data set. See this plot for details.
There should be only 2 peaks, one for e-nitrogen elastic and the other for eP elastic events. This issue
happened to the data set when the right septum is under 40-32-16 configuration.
2) Jixie mentioned that the energy difference between the first e-nitrogen peak to the next e-nitrogen peak is
about 70 MeV, assuming the momentum reconstruction is right (we know that the momentum reconstruction
in the plot is valid only for without target field situation). The scattering angle for these two peaks
are 5.6 and 9.8 degrees, respectively.
3) JP suggested that the septum field might fluctuate during the run.
4) Ryan, Chao checked the date and found that these run were taken right before the septum shorted
for the 2nd time which caused the 2nd failure. Melissa agrees to check the magnet history using the epics
variable record.
5) Melisa also agreed to make a list of the run numbers which have this issue and provide it to Ryan for updating
the mysql database.

  • Chao:

1) Working on analyzing target field measurement data. Have some preliminary results here
The field was measured on 4 pieces of grid paper. The measured Br( in the direction perpendicular
to the chamber surface) agree with the Tosca model very well (most of them are within 1% and some of them are within 2%).
Check the xls file for detail. Chao will give a final report net week.


Status Updates:

  • Jixie:

1) Working with simulation to find out if we can do focal plane to sieve plane reconstruction.
There is some issues going on with the SNAKE model in the G4 code, see here for details.

  • Ryan:

1) Updated the web interface page for the mysql database

  • Toby:

1) Cross check on raster reconstruction. One plot is posted here for the BPM current and raster patter

  • Min:

1) The analyzer database was posted on the wiki here.
2) working on optics optimization

  • Jie:

1) working on shower and pre-shower calibration.

08/29/2012

Present: Jixie, JP, Min, Melissa, Kalyan, Pengjia, Alex, Jie, Vince, Chao
By-Phone: Ryan, Toby

General Discussion:


Feature Presentation:

  • Pengjia & Alex:

1) BPM calibration status update
Pengjia is working hard to find a formula for beam position reconstruction.
2) Alex posted the heat capacity measurements for the tungsten calorimeter in the elog,entry 173
The result shows that the relative standard deviation of heat capacity (measured by RTD) is 0.15%.

Status Updates:

  • Ryan:

1) working on optics for cross check, adding missing info to mysql database

  • Toby:

1) working on raster reconstruction, cross check Pengjia's work

  • Min:

1) finished splitting db_run.
2) working on optics

  • Melissa & Jie:

1) Cross checked the CherenKov calibration. Showed the final results.
The single photon electron peak from the results presented last week was the maximum value.
It was just misspoke in previous meeting.
2) Both will move on to do shower and pre-shower calibration.

  • Chao:

1) working on analyzing target field measurement data.


08/22/2012

Present: Jixie, JP, Min, Melissa, Kalyan, Pengjia, Alex, Jie, Vince
By-Phone: Ryan, Karl, Toby

General Discussion:

Feature Presentation:

  • Melissa & Jie:

1) Melissa showed her Cherenkov calibration for the right arm, see details here
2) Jie pointed out that Melissa is using the most probable value from the gauss*landau fit.
While we had concluded that the maximum value should be used in the past. After rechecking Jie's fitting result table,
there seems to be some puzzle in the label or the physical meaning of some variables. Jie and Melissa
agreed to double check their results and give a final report in the next meeting.

  • Jixie:

1) Showed the study on the FZ2 magnetic field at BPM 1H05A and 1H05B location. Jixie concluded that
the FZ2 field's effect will be less than 4x10^-4, which is negligible. See details here.
2) Obtained confirmation from the survey group that the report of the grid paper for the target field
measurement is the right one. Will analyze the data soon.

Status Updates:

  • Min & Chao:

1) Min's splitting the left and right db_run from one big file for 'replay' program.
Because replay only check the time stamp to extract constants from file 'db_run',
there is a potential issue that right arm reconstruction will read left arm constants
from db_run if left and right arm constants are in one file.
2) Chao finished updating the program 'tree2ascii' which is used to select good sieve data.
It now selects a given number of events for each sieve hole.
3) Chao organized the replay program such that all variable leaves will be stored into one tree,
which is required by program 'tree2ascii'.

  • Pengjia & Alex:

1) Working on BPM calibration, the formula to reconstruct position seems not working well.
2) Alex agreed to get the uncertainty for RTD and also the uncertainty of the heat capacity
of the Tungsten calorimeter.

  • Ryan:

1) The Mysql database is ready! Web interface is also available now. Check here for details.
Jixie suggested to add some descriptions or definitions on the page such that users will know
what those encoded numbers mean.

  • Toby:

1) Crosschecking BPM calibration.

08/15/2012

Present: Jixie, JP, Min, Chao, Melissa, Kalyan, Pengjia, Alex
By-Phone: Ryan, Karl, Toby

General Discussion:

Feature Presentation:

  • Melissa:

1) Checked the Cherenkov calibration for all momentum settings for the left arm.
Melissa show a nice figure which shows the single photon electron peak averaged
over 10 PMTs. See details here.
2) Will check the right arm soon.

  • Pengjia:

1) Working on BPM calibration. In his slides Pengjia showed 3 methods to do
the BPM reconstruction, but none of them have good linearity. JP suggested to solve the equation and
use the analytic solution of it.
2) Discussed the BPM calibration status. Jixie suggest Pengjia to finish the machinery code for each
module then improve some of them later. Therefore Pengjia will have the whole project working before he leaves,
and he can improve it in China. JP suggests Pengjia to finish the most important module then move to the next.
3) Pengjia asked Toby to cross check the raster shape reconstruction and then perform the fit from the BPMs to Target.

Status Updates:

  • Jixie:

1) Ran simulation to test the focal plane to sieve reconstruction strategy.
2) Agree to contact Yves for tosca map for FZB2.
3) Finished up the target field measurement project. Need to ask survey group to provide another survey report.

  • Toby:

1) Working on target material analysis. Finished calibration for some of the materials. The material table on
the wiki has been updated with the calibrated results.
2) There is some 5-7 sigma discrepancy between Toby's target analysis result and James's. Toby is trying to
find out the reason.
3) Karl stated that Dustin is still doing g2p target analysis. H e suggested Toby to work with Dustin.

  • Ryan:

1) Finished reading logs and building run information. The MYSQL database is ready in his PC. Will setup one
database on the JLab farm soon. Web interface will also be available by then.
2) Relative information will also be posted in the wiki.
3) will start optics optimization soon.

  • Min:

1) Just back from China. Will continue optics work.

  • Chao:

1) G2p reconstruction ntuple missing some epics variable due to some mistakes during the run. These epics
variables can be extract from epics log files. Need to work on the replay to take these variables from the log
files and insert them into the ntuple. Almost done.
2) Once 1) is finished, will move on to update optimization program to take equal number of events from each
hole.


08/01/2012

Present: Jixie, Jie, Melissa, Kalyan, Pengjia, Vince, JP
By-Phone: Ryan, Karl

General discussion:
 1) The posters and abstracts for GRC are ready for review. Please send
your comments to the author ASAP. The final version of the posters and
abstracts will be posted on the WIKI.
2) Pengjia and Chao will give talks at the coming Chiral Dynamic conference.
They will practice their talks This Friday (Aug. 3rd) 2 PM. Vince will find
a room and send email out.
3) Vince agreed to conduct the tour to Hall A for the Chiral Dynamic participants
next Thursday (Aug 8th). 4) JP is worrying about the optics calibration might slow down the analysis.


Status Update:

  • Ryan:

1) Finished reading the halog. A TPYE has been signed to each run. All work is done
in his PC. Will transfer to Jlab MYSQL database later. Ryan will also write a web
interface to read the MYSQL database.
2) Learning how to run optics optimization program. Will work on this soon.

  • Chao:

1) Stayed at UVA last week.
2) Working on optics packages. Trying to select the same number of events from each hole
to avoid bias in the optimization.
3) Finished the write up for helicity decoding, see details here
4) Preparing slices for CD2012

  • Jie & Melissa:

1) Continue Cherenkov calibration. Jie Scaled the single photo-electron peak to 100( adc channel #).
He chose to average the whole g2p data set instead of split them into multiple sets. See his result here
2) Melissa check Jie's fitted result with one beam energy data set. The result looks good. The
calibrated single photon-electron peak are very closed to 100. See here for details.
3) Melissa will check for other beam energy data sets.

  • Pengjia:

1) BCM calibration is done except the uncertainty. Need to know the uncertainty for the heat
capacity of the Tungsten Colorimeter. JP suggested to survey the manufacture for this information.
2) Working on BPM calibration. Pengjia agreed to present the basic knowledge about the BPM calibration
in next meeting. He will also post some documents about BPM calibration onto the wiki.


7/25/2012

Present: Jixie, Jie, Melissa, Kalyan, Pengjia By-Phone: Ryan, Toby

General discussion:
 1)The posters and abstract of Ryan and Melissa is ready for review. Please send
them your comments. Toby's is also ready!
2)Hall A counting house will be renovated soon. Adaql# machine will not
be accessed from July 26,2012. Please back up your files!
Jixie has transfered ~adaq/g2p to /w/halla-1/g2p/g2p_at_adaqlX.tar.gz


Status Update:

  • Pengjia:

1) Showed BCM calibration procedure. See this for detail.

  • Jie & Melissa:

1) Fitted the single photon-electron peak with gauss-landau function and compared the result with
pure gauss fittings. Jie's result provides 2 sets of values: one is
most likely peak value and the other is maximum peak value. The maximum peak value is very closed to
the gaussian fitted result (within 2 channels, about 3%).
It is also very closed to Melissa's result. Kalyan and Jixie suggested to use the maximum peak value in the calibration.

  • Ryan:

1) continue working on run information for the mysql database. 1000 runs to go for left arm. Will
start right arm data after then.
2) follow up the ccpr about creating mysql server in the jlab farm.
3) learning optics optimization.

  • Toby:

1) abstract of the poster for GRC is ready for review.


7/18/2012

Present: Jixie, Vince, Jie, Chao, Kalyan, Pengjia By-Phone: Karl

General discussion: This meeting starts at 14:30 every Wednesday from next week!

Status Update:

  • Chao:

1) Continue optics analysis. Trying to select 1000 good particles from each hole to do
the optimization
2) Finished checking optics run
3) Writing a program to insert HALLA:p and HALLA:dpp into the replay ntuple output.

  • Pengjia:

1) BCM calibration is finished. A python code is ready to extract BCM calibration constants
for a given run number. Here is Pengjia's original words:

Hi Everyone,
I built a python class to get the bcm constant, you can find the code in: /w/halla-1/g2p/codeshare/bcm/bcmconst.py
You just need to give it run number, device(sis3800,sis3801 or happex),upstream or downstream, clocktype(fast or slow clock), you can find the example and usage in that code(__main__ part). This code will read bcm constant from the spreadsheet which I posted in wiki one to two months ago(in https://hallaweb.jlab.org/wiki/index.php/G2p_BCM_calibration), you can assign filename, or it will automatic download the file from the wiki.
Also you will need to download odsread.py file in the same directory(/w/halla-1/g2p/codeshare/bcm/odsread.py) which I wrote for reading ods file(openoffice spreadsheet), you can also use it to read any other ods files. If you find any bugs please let me know. Thanks!
Pengjia

2) Continue working on BPM calibration

  • Jie:

1) Applied a different TDC cut (which will remove the peak TDC) before fitting the single photon
electron position. This cut removes the plateaus in the photon-electron distribution.
This result is posted here[Cerenkov SPE peak calibration http://hallaweb.jlab.org/experiment/g2p/collaborators/jie/2012_07_18_Cer/Cerenkov.pdf]. Kalyan suggested to add landau tail to the fit
which might improve the result. Jie agrees to try this and cross check with Melissa's result

7/3/2012

Present: Jixie, Vince, Ryan, Melissa, Jie, Alex, Chao, Toby, Kalyan, Pengjia, Min By-Phone: Karl

General discussion: No meeting for next week!

Status Update:

  • Ryan:

1) Working on reading HaLogs and assigning run type for every run
2) Reported that the HWP status in the epics file tripped quite often (flip within seconds)
But there are plenty of solutions to achieve the status of HWP for a run.

  • Min:

1) Working on improving the optimization. Will apply the following:
A) Select events from all of the holes if possible
B) Equally weight each hole
C) Add delta=+/- 3% data events into the optimization table

  • Chao:

1) Creating a table which will describe the detail information for all optics runs
2) The name of two optics summary file are wrongly labeled. Jixie will fixed it.

  • Jie:

1) Worked on Cherenkov calibration. In fitting the single phone electron peak, he found that
there are about 10 ADC channel difference between a Gaussian fit and Gaussian+pol3 fit.
Melissa and Jie will cross check there work.

  • Melissa:

1) Optimizing the fit for signal photon electron peak
2) Working on extracting the efficiency for left and right PMTs in Left HRS

  • Toby:

1) Wrote a script to determine the average target polarization for a given run
Karl suggested to look at the change of polarization within a run, trying to remove
bad|junk events
2) Crossing check Pengjia's Harp data calibration

  • Pengjia:

1) Rewriting the program to calibrate BPM, still need to contact John for N15 BPM drawings

6/27/2012

Present: Jixie, Vince, Ryan, Melissa, Jie, JP, Chao, Toby, Kalyan, Pengjia By-Phone: Karl

Feature Presentation:
1) Melissa: Cherenkov Calibration)
A) Isolated single photon-electron peak with cuts.
JP suggested to fit with double peak function for some PMTs
B) Checked consistency
C) TODO: stability check and efficiency calculation

2) Min|Jixie: Left HRS straight through optics calibration
A) dp calibration shown
B) theta,phi angle calibration shown, still need to improve: will cut VZ out and
select equal number of events from each hole to avoid bias.

3) Chao: Report the helicity decoder status.


Status Update:

  • Toby:

1) Continue the TE analysis

  • Ryan:

1) checking halogs for run information. Will update the mysql database.

  • Pengjia:

1) check epics data for HALLA:p, no data lost. Have scripts ready to extract
epics values and insert them into root file
2) BPM calibration:
A) Need survey data of the longitudinal setting. Already contact survey group
B) Asked John to provide engineering drawing for the N15 BPM
C) Will transfer Yves's trajectories into Hall A coordinate system

  • Jie:

1) Continue working on Cherenkov calibration


6/20/2012

Present: Jixie, Min, Pengjia, Melissa, Jie, Alex, JP, Chao, Toby, Kalyan, Ryan, Vince By-Phone: Karl

Feature Presentation:
1) Toby: Target_analysis_update)
TE analysis is done for one point, details is shown in the above link, 39 points to go

2) Chao: Updating db_run.dat, see details here. A) Reported that 'end of run time' can be accessed with 3 methods, some methods do not work.
Vince suggested to also look into event type 100 in the raw data file.
B) Averaged epics variables in a run by run manner
C) HALLA:p is missing in the raw data. It sometimes even disappeared in the epics files. Pengjia will look
into this.
D) Removed helicity decoder from replay. Will do the helicity replay separately and store the result
into a table. This table will be inserted into the output ntuple each time the replay is running.

Status Update:

  • Jie:

1) doing an independent check of the Cherenkov calibration. Working on A)the pedestal for each PMT
and B)Align single photo-electron peak for each PMT.

  • Ryan:

1) Average the epics variable in a run. Can cross check with Chao's result
2) Sign a flag to each run based on all information(from student log, shift workers' log,etc...)

  • Melissa:

1) Checking the consistency of the Cherenkov calibration.

  • Min:

1) Checked materials and thickness that an incoming electron and an outgoing electron will go through,
reports posted in the elog entry 172
2) Put the survey information into the program and optimize straight through optics

  • Pengjia:

1) Split the halog by author such that it will be convenient for searching. New halog is posted here.
2) Will check the epics for missing variable issue.
3) Working on BPM calibration.

  • Jixie:

1) Organized the survey web. Talked with Jim for the right HRS survey which is done before the
experiment. The report for the HRS survey done after experiment is ready. Sieve and local dump survey
was done this Monday and the report are in progress.


6/12/2012

Present: Jixie, Min, Pengjia, Melissa, Jie, Alex, JP, Chao, Toby, Ryan, Vince, Kalyan By-Phone:

Feature Presentation:
1) Min: analysis database (run information table)
Beam energy, start time, P0, Theta0 for each run have been written into the table
107 runs are still missing. Chao will take care of these runs.

2) Jie: Finished VDC T0 calibration.

Status Update:

  • Ryan:

1) Updated target_encoder, HWP status, prescale factors in the mysql database. See details here.

  • Pengjia:

1) BPM: obtained noise for every gain setting
2) BCM: Gain is unstable before March 10. Need absolute uncertainty of calibration. Alex will look into it.

  • Toby:

1) Picking out good TE measurements. Match TE points to the right material. Will do new fits.
2) Updated target log book on the wiki.

  • Chao:

1) Improved helicity decoder
2) Will prepare run information table for further analysis

  • Melissa:

1) Working on Cherenkov calibration


5/30/2012

Present: Jixie, Min, Pengjia, Melissa, Jie, Xiaochao, JP, Chao, Toby, Melissa By-Phone: Karl, Guy

General discussion (JP, Karl, ...):
1) Chiral Dynamics Workshop will be held at Jlab in Aug 6-10. The deadline for submission is June 1.
Please submit abstract.
2) Gorden conference will take place at the same time. Submit abstract before deadline!
3) G2P group will give 3 talks for the Hall-A collaboration meeting .
We will meet next Wednesday 13:00-15:00 to practice the talks and giving feed-back.
Jixie has reserved L207. (Jun 6, 13:00 - 15:00).
4) Karl will provide plot|slice material to Bob and Jixie for their talks in Hall A collaboration meeting.

Feature presentation:
 1) Pengjia: Preliminary BCM calibration Result

Status Update:

  • Guy:

1) Have analysis meetings in Israel. Analyzing the data.
2) Need to discuss how to do the dilution factor calculation.

  • Jixie:

1) working on optics analysis.

  • Min:

1) Calculating the uncertainty of pointing. Discussing with Nilanga about it.

  • Chao:

1) Working on helicity reconstruction. Need Pengjia to cross check this when finish.
2) will cross check BCM calibration soon.

  • Toby:

1) Preparing the target material TE table for target calibration.

  • Jie:

1) Working on VDC T0 calibration. Need more statistics to get the result.

  • Melissa:

1) Working on CC calibration.

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