View source for He3 / H3 e,e'p experiment E12-14-011

* [[http://hallaweb.jlab.org/wiki Back to Hall A wiki]]

The SRC Tritium Experiment (E12-14-011) is an (e,e'p) experiment in Hall A, comparing the momentum distribution of protons in tritium and helium-3. These nuclei have a large proton-neutron asymmetry, but are also isospin-mirror nuclei, meaning that the proton distribution in tritium can tell us about the neutron distribution in helium-3. 

== Important codes ==

* replay script can be found here:
https://github.com/reynier0611/HallA-Online-Tritium/tree/coincidence
(Make sure to be in the "coincidence" branch)

* skimmer and combiner codes can be found here:
https://github.com/reynier0611/tritium_eep_skimmer

== During the experiment ==
The information that was more relevant for activities during the data-taking period will be moved from this page to the following new page:
* [[Data-taking period]]

== Beam Energy Calibration ==
[https://www.jlab.org/indico/event/197/session/3/contribution/12/material/slides/0.pdf Done by D. Higinbotham] ([[This is a 'pass-dependent' statement]])

For second pass beam, use the Tiefenbach energy multiplied by 1.0025(5)

(That is, replace the value Ebeam in db_run.dat by 1.0025xEbeam)

After this correction, the measured Ebeam (before Eloss corrections) is '''~ 4.3255 GeV'''

[http://hallaweb.jlab.org/equipment/beam/energy/arc_web.html check this too]

== Raster Calibration ==

[[More details here]]

== Target Information ==
* [https://logbooks.jlab.org/files/2018/01/3514205/TGT-RPT-17-007.pdf Tritium Target Tech. Note]
* [https://logbooks.jlab.org/files/2018/01/3510390/DT_A1845.pdf Target Ladder Alignment Survey January 2018]
* [https://hallaweb.jlab.org/wiki/images/0/06/H3_target_info_summary.pdf Information from Jesse]
* [https://logbooks.jlab.org/files/2017/12/3501699/TGT-CALC-17-020.pdf Target Densities (TGT-CALC-17-020)]
* [https://logbooks.jlab.org/files/2018/11/3619916/TGT-CALC-17-020.pdf Target Densities (TGT-CALC-17-020) <- NEW ONE]
* [https://hallaweb.jlab.org/wiki/images/7/7b/Tritium_decay.pdf Helium contamination in tritium target - by Tyler Kutz]

{| style="border: 1px solid black;"
|- 
!Target
!density [mg/cm2]
|-
!Hydrogen
!70.8 +/- 0.4
|-
!Deuterium
!142.15 +/- 0.8
|-
!Tritium
!85.1 +/- 0.8
|-
!Helium-3
!53.4 +/- 0.6
|-
|}

== HRS Angles, Surveys, and Mispointings ==
* Spectrometer Surveys
** [https://hallaweb.jlab.org/wiki/images/3/34/L-HRS_Tritium%284-17-2018%29.pdf LHRS Survey, April 17 (during slow and fast2 kinematics)]
** [https://hallaweb.jlab.org/wiki/images/6/61/R-HRS_Tritium%284-17-2018%29.pdf RHRS Survey, April 17 (during slow kinematics)]
** [https://hallaweb.jlab.org/wiki/images/3/37/DT_A1860.pdf RHRS Survey, April 30 (during fast2 and hydrogen2 kinematics)]
** [https://hallaweb.jlab.org/wiki/images/9/98/DT_A1861.pdf LHRS Survey, May 2 (during hydrogen kinematics 2)]

=== LVDT retults ===
{| style="border: 1px solid black;"
|- 
!Kinematics
!Run number
!L mispointing [mm]
!R mispointing [mm]
!LHRS angle [deg]
!RHRS angle [deg]
|-
!Fast
!100085
!1.18245
!-0.70915
!20.8837
!48.8207
|-
!Hydrogen
!100100
!0.9882
!-0.7113
!17.8017
!48.8207
|-
!Slow
!100532
!0.48765
!-0.65395
!20.8812
!58.5031
|-
!Fast2
!100658
!0.49145
!-2.9875
!20.8812
!48.8187
|-
!Hydrogen2
!100685
!0.8831
!-3.00255
!17.8053
!48.8188
|-
|}

== HRS Momenta ==
Values taken from db_run.dat file.

{| style="border: 1px solid black;"
|- 
!Kinematics
!Run number
!LHRS p_cent [GeV]
!RHRS p_cent [GeV]
|-
!Fast
!100085
!3.54334
!1.48051
|-
!Hydrogen
!100102
!3.54334
!1.4805
|-
!Slow
!100532
!3.54331
!1.246
|-
!Fast2
!100658
!3.5433
!1.48051
|-
!Hydrogen2
!100685
!3.5433
!1.4805
|-
|}

== Optics ==
[http://web.mit.edu/reynier/www/Tritium_optics_matrices/LHRS_current_optics.html current LHRS matrix]

[http://web.mit.edu/reynier/www/Tritium_optics_matrices/RHRS_current_optics.html current RHRS matrix]

[[More information can be found here]]

== Other information ==

* Kinematics [https://hallaweb.jlab.org/wiki/images/8/87/Main_kinematics.pdf MORE DETAILS HERE]

These are the nominal values we got by optimizing in simc (these are not the actual values from the experiment)
{| style="border: 1px solid black;"
|- 
! Kinematics
! LHRS momentum [GeV]
! LHRS angle [deg]
! RHRS momentum [GeV]
! RHRS angle [deg]
|-
! Fast
! 3.543
! 20.88
! 1.4805
! 48.80
|-
! Slow
! 3.543
! 20.88
! 1.246
! 58.50
|-
! Parallel (Hydrogen)
! 3.543
! 17.80
! 1.4805
! 48.80
|}

* '''BCM calibration'''
** run number: 100172
** target: carbon foil
** currents and attenuator values:
***      3uA ---> 140
***      7uA ---> 163
***    12uA ---> 184
***    18uA ---> 204
*** 22.2uA ---> 214
**These are nominal values for the beam current. Gotta get the actual values from epics info.
** See example in the halog, entry number: 3505501

* '''Unser calibration'''
** run number: 100451
** target: dummy
** current values: 0,2,0,3,0,5,0,10,0,25,0,40,0,60,0,80,0,90,0,100,0,2,0,3,0,5,0,10,0 uA
** Ideally we would have completed two full cycles from 0 to 100 uA, but the beam came back and we decided to go back to production.
** See example in the halog, entry number: 3499263

== Root files on Tape ==
Actual raw data: /mss/halla/triton/raw/

July 10th, 2018: [[/mss/halla/triton/prod/coinc_eep/pass2.1/all/]]

July 27th, 2018: [[/mss/halla/triton/prod/coinc_eep/pass2.2/all/]]

August 10th, 2018: [[/mss/halla/triton/prod/coinc_eep/pass2.3/all/]]

== Documentation == 
* [https://docs.google.com/spreadsheets/d/1Kt_5uLLEZvaStKJK1RfV_C5BNUpuJaaEfpH8UXgCA3k/edit#gid=0 Run List]
* [http://hallaweb.jlab.org/12GeV/experiment/E12-07-108/Publications/Technical/Spectrometer/Fall16/Right&Left_HRS_GMP_Fa16.pdf For collimator cut]
* [https://hallaweb.jlab.org/wiki/images/d/df/18_04_04_Tritium_%28e%2Ce%27p%29_v3.pdf Experiment seminar slides]
* [https://hallaweb.jlab.org/wiki/images/b/bb/18_04_06_Run_Plan.pdf Run and online analysis slides]
* [[Raster]]
* [[HRS DAQ Resources]]
* Simulation
** [[Using MCEEP]]
** [[Using SIMC]]
** [[Using COSY]]
* [[Tel Aviv University SRC group]]
* [https://hallaweb.jlab.org/experiment/Tritium/E12-11-112/tritium_page/runlist.php?exp=EPrunlist&runtype=All&hrs=all&target=All&keyword=&submit=search MySQL Database]

=== Reference Reading === 

* [https://hallaweb.jlab.org/wiki/images/2/26/PR12-13-012.pdf Proposal ] for E12-14-011, approved by PAC-42
* [http://hallaweb.jlab.org/equipment/Hall-A-NIM.pdf Hall-A NIM paper (2004)]
* [http://hallaweb.jlab.org/publications/Technotes/files/2002/02-012.pdf Tech notes on HRS optics calibration]
* [https://misportal.jlab.org/ul/publications/view_pub.cfm?pub_id=12877 Hall A Coordinate systems (Ye Zhihong PhD thesis)]
* [http://hallaweb.jlab.org/equipment/HRS.html HRS info]

=== Previous (e,e'p) studies ===

* [http://hallaweb.jlab.org/experiment/E89-003/e89003.html Hall-A E89-003 16O(e,e'p) experiment]
* [http://hallaweb.jlab.org/experiment/E07-006/ Hall-A E07-006 4He(e,e'p) experiment]

== Meetings ==

=== Weekly SRC Meetings (Wednesdays 9:30 ET) ===

* [[Files (SRC Meetings)]]

=== Bi-weekly Tritium SRC Analysis Meetings (Every Other Tuesdays 10:00 ET)===
* [[SRC Analysis Meetings]]