Moller Polarimeter/Qweak
General Information
This is the spot for all things moller polarimetry. Information on how to take moller measurements, spin dance and polarimetry results, and system specs will eventually be put here. This page is currently under construction, and will be updated frequently in the upcoming weeks.
Preliminary results
Measurments for 2011
Last updated Feb. 22, 2011
Measurments for 2010
Note: Measurement on "Day 39" low due to likely hardware issue.
Moller info for Qweak
- The Qweak Moller "how to" is officially up and ready for viewing. (version 1, updated jan. 26, 2011): Qweak Moller "How-To"
- The following is a plot showing good tune of the apparatus. It was taken from run 700, hallc:p ~ 1159 MeV, with a 1um target. (Jan. 30, 2011)
Table of good Moller runs
The following are runs made from straightforward moller test runs, not spin dances. Note, missing data can/will be added over time. The Nov. 14, 2010 commissioning run is NOT included. (we were messing with camac pre-scales, et cetera.)
Date Run Polarization (%) HW Plate Wien (deg.) HALLC:p(MeV) QE(%) Foil (um) Current (uA) Comments
1/21/11 686 -90.46 +/- 0.52 0 (IN) 1159.82 0.32 1 1
687 -91.36 +/- 0.69 0 (IN) 1159.82 0.32 1 1.5
688 -90.60 +/- 0.67 0 (IN) 1159.82 0.32 1 2.0
689 -91.64 +/- 0.99 0 (IN) 1159.82 0.32 1 1.5
691 -91.28 +/- 1.43 0 (IN) 1159.82 0.32 1 0.5
1/30/11 702 -90.07 +- 0.63 1159 1 0.8 New HV L 1510V, R 1535V
703 -88.75 +- 1.31 1159 1 0.8 New HV L 1510V, R 1535V
704 -90.48 +- 0.71 1159 1 0.8 New HV L 1510V, R 1535V
705 -89.84 +- 1.15 1159 1 0.8 Old HV L 1480V, R 1520V tripped at end
706 -89.31 +- 1.09 1159 1 0.8 Old HV L 1480V, R 1520V tripped at end
708 -89.37 +- 0.78 1159 1 0.8 Old HV L 1480V, R 1520V
709 -89.92 +- 1.50 1159 1 0.8 HV L 1530V, R 1555V
710 -88.15 +- 0.72 1159 1 0.8 HV L 1610V, R 1655V
711 -89.77 +- 0.72 1159 1 0.8 HV L 1610V, R 1655V
712 -88.08 +- 0.72 1159 1 0.8 HV L 1610V, R 1655V
2/4/11 721 -88.37 +- 0.70 0 (IN) 1159.76 0.637 1 0.96
722 -88.94 +- 0.73 0 (IN) 1159.76 0.637 1 0.96
723 -89.14 +- 0.73 0 (IN) 1159.76 0.637 1 0.96
724 89.20 +- 0.70 1 (OUT) 1159.76 0.637 1 0.96
725 89.06 +- 0.73 1 (OUT) 1159.76 0.637 1 0.96
726 88.97 +- 0.73 1 (OUT) 1159.76 0.637 1 0.96
2/7/11 737 89.09 +- 0.70 1 (OUT) 1159.6 0.04192 1 1
738 88.28 +- 0.73 1 (OUT) 1159.6 0.04192 1 1
739 88.81 +- 0.67 1 (OUT) 1159.6 0.04192 1 1
740 -86.99 +- 0.68 0 (IN) 1159.6 0.04192 1 1
741 -87.31 +- 0.7 0 (IN) 1159.6 0.04192 1 1
742 -88.52 +- 0.73 0 (IN) 1159.6 0.04192 1 1 beam tripped
743 -87.52 +- 0.73 0 (IN) 1159.6 0.04192 1 1
2/8/11 747 88.46 +- 0.73 1 (OUT) 1 charge asymmetry -128 ppm
748 89.49 +- 0.73 1 (OUT) 1 charge asymmetry -153 ppm
749 87.47 +- 0.74 1 (OUT) 1 charge asymmetry 94 ppm
750 88.39 +- 0.73 1 (OUT) 1 charge asymmetry -195 ppm
751 -87.63 +- 0.65 0 (IN) 1 charge asymmetry 1305 ppm
752 -87.99 +- 0.81 0 (IN) 1 charge asymmetry -1734 ppm
753 -88.57 +- 0.69 0 (IN) 1 charge asymmetry -300 ppm
754 -88.10 +- 0.72 0 (IN) 1 charge asymmetry -257 ppm
755 -87.63 +- 1.12 0 (IN) 1 charge asymmetry -234 ppm
2/14/11 803 -87/52 +- 0.69 1 (OUT) -62.39 1159.61 0.1968 1
804 -89.58 +- 0.72 1 (OUT) -62.39 1159.61 0.1968 1
805 -89.74 +- 0.77 1 (OUT) -62.39 1159.61 0.1968 1 beam trip
806 -89.15 +- 0.72 1 (OUT) -62.39 1159.61 0.1968 1
815 89.66 +- 0.73 0 (IN) -62.39 1159.61 0.1968 1
816 88.94 +- 0.67 0 (IN) -62.39 1159.61 0.1968 1
817 89.00 +- 0.70 0 (IN) -62.39 1159.61 0.1968 1
2/19/11 826 -89.24 +- 0.72 1 (OUT) -62.39 1159.62 1 tune funny prior to this run, recylced quads
827 -88.76 +- 0.73 1 (OUT) -62.39 1159.62 1
828 -88.78 +- 0.71 1 (OUT) -62.39 1159.62 1
830 90.73 +- 1.40 0 (IN) -62.39 1159.62 1 large charge asymmetry
831 88.64 +- 0.99 0 (IN) -62.39 1159.62 1
832 89.87 +- 0.72 0 (IN) -62.39 1159.62 1
834 89.28 +- 0.72 0 (IN) -62.39 1159.62 1
835 91.91 +- 0.69 0 (IN) -62.39 1159.62 1
836 89.75 +- 1.35 0 (IN) -62.39 1159.62 1
2/22/11 842 -89.44 +- 0.73 1 (OUT) -62.39 1159.73 0.3480 1 Prescales at infinity and Q3=131A
843 -89.61 +- 0.71 1 (OUT) -62.39 1159.73 0.3480 1
844 -89.24 +- 0.71 1 (OUT) -62.39 1159.73 0.3480 1
845 -88.92 +- 0.73 1 (OUT) -62.39 1159.73 0.3480 1
847 89.93 +- 0.73 0 (IN) -62.39 1159.73 0.3480 1
848 88.58 +- 0.73 0 (IN) -62.39 1159.73 0.3480 1 Moller ended early due to 2K cold box trip
List of leakage checks
Run Date Absolute rate (Hz) Active halls Comments 515 11/23/10 0 A we should double check this, if there is any nice retroactive way 518 11/23/10 0 A 744 2/7/11 2 774 2/8/11 1-2 B 819 2/14/11 1-2 8829 2/19/11 10 A+B 846 2/22/11 5
List of good Moller spin dance runs (this can be combined with the above table, if desirable) The HWP column has a (L) for flipped left, and (R) for flipped right.
Date Run Polarization (%) HW Plate Vert. Wien (deg.) Horiz. Wien HALLC:p(MeV) QE(%) Comments
11/23/10 508 c +40.04 +/- 1.23 1 (OUT) -0.1 1159.66 0.35 1 um foil, 200 nA
509 c +40.05 +/- 1.88 1 (OUT) -0.1 1159.66 0.35 1 um foil, 1.05 uA
510 +40.40 +/- 1.03 1 (OUT) -0.1 1159.66 0.35 1 um foil, 1 uA
511 +40.13 +/- 0.68 1 (OUT) -0.1 1159.66 0.35 1 um foil, 0.9 uA
512 +40.19 +/- 0.70 1 (OUT) -0.1 1159.66 0.35 1 um foil, 0.9 uA
513 +40.13 +/- 0.70 1 (OUT) -0.1 1159.66 0.35 1 um foil, 0.9 uA
514 +40.14 +/- 0.65 1 (OUT) -0.1 1159.66 0.35 1 um foil, 0.57 uA
517 -2.75 +/- 0.65 1 (OUT) +29.0 1159.66 0.35 1 um foil, 0.9 uA
519 -3.70 +/- 0.69 1 (OUT) +29.0 1159.66 0.35 1 um foil, 0.9 uA
520 -3.48 +/- 0.68 1 (OUT) +29.0 1159.66 0.35 1 um foil, 0.9 uA
521 +75.85 +/- 0.88 1 (OUT) -31.0 1159.66 0.35 1 um foil, 0.9 uA
522 +76.81 +/- 0.69 1 (OUT) -31.0 1159.66 0.35 1 um foil, 0.9 uA
523 +75.61 +/- 0.69 1 (OUT) -31.0 1159.66 0.35 1 um foil, 0.9 uA
524 +75.50 +/- 1.25 1 (OUT) -31.0 1159.66 0.35 1 um foil, 0.9 uA
525 +74.54 +/- 0.96 1 (OUT) -31.0 1159.66 0.35 1 um foil, 0.9 uA
526 +75.37 +/- 0.67 1 (OUT) -31.0 1159.66 0.35 1 um foil, 0.9 uA
527 +87.89 +/- 0.70 1 (OUT) -75.0 1159.66 0.35 1 um foil, 0.9 uA
528 +87.63 +/- 0.69 1 (OUT) -75.0 1159.66 0.35 1 um foil, 0.9 uA
529 +86.69 +/- 0.69 1 (OUT) -75.0 1159.66 0.35 1 um foil, 0.9 uA
530 +86.83 +/- 0.79 1 (OUT) -75.0 1159.66 0.35 1 um foil, 0.9 uA
531 +88.64 +/- 0.74 1 (OUT) -63.0 1159.66 0.35 1 um foil, 0.9 uA
532 +89.65 +/- 1.12 1 (OUT) -63.0 1159.66 0.35 1 um foil, 0.9 uA
533 +90.32 +/- 0.69 1 (OUT) -63.0 1159.66 0.35 1 um foil, 0.9 uA
534 +89.51 +/- 0.68 1 (OUT) -63.0 1159.66 0.35 1 um foil, 0.9 uA
535 +89.73 +/- 1.90 1 (OUT) -63.0 1159.66 0.35 1 um foil, 0.9 uA
536 +90.04 +/- 0.91 1 (OUT) -63.0 1159.66 0.35 1 um foil, 0.9 uA
2/10/11 771 -85.92 +/- 4.22 1 (OUT)L -63.22 87.10
772 -90.36 +/- 0.73 1 (OUT)L -63.22 87.10
773 -88.62 +/- 0.73 1 (OUT)L -63.22 87.10
776 -73.81 +/- 0.74 1 (OUT)L -30 87.10 good (energy not reading back)
777 -76.53 +/- 0.74 1 (OUT)L -30 87.10 good (energy not reading back)
778 -75.89 +/- 0.75 1 (OUT)L -30 87.10 good (energy not reading back)
779 -74.29 +/- 0.74 1 (OUT)L -30 87.10 good (energy not reading back)
780 -76.13 +/- 0.92 1 (OUT)L -30 87.10 good (energy not reading back)
781 -75.18 +/- 0.71 1 (OUT)L -30 87.10 good (energy reading back)
782 -74.71 +/- 0.74 1 (OUT)L -30 87.10 good
783 -41.87 +/- 0.73 1 (OUT)L -1 87.10 good
785 -42.10 +/- 0.74 1 (OUT)L -1 87.10 good, 3c12 unstable
786 -42.62 +/- 0.74 1 (OUT)L -1 87.10 good, 3c12 unstable
787 -77.27 +/- 0.72 1 (OUT)L -90 87.10 good, 3c12 unstable
788 -76.99 +/- 0.73 1 (OUT)L -90 87.10 good, 3c12 unstable
790 -77.44 +/- 0.74 1 (OUT)L -90 87.10 good
791 -89.00 +/- 0.73 1 (OUT)L -62.4 87.10 good
792 -89.76 +/- 0.82 1 (OUT)L -62.4 87.10 3c12 drifting
793 -88.66 +/- 0.73 1 (OUT)L -62.4 87.10 3c12 drifting
794 +88.92 +/- 0.73 0 (IN)L -62.4 87.10 large charge asymmetry ~1166ppm
795 +90.77 +/- 2.74 0 (IN)L -62.4 87.10 charge asymmetry ~1052 ppm, Pockel's HV change
796 +88.82 +/- 0.73 0 (IN)L -62.4 87.10 charge asymmetry ~ 379, good
797 +87.87 +/- 0.73 0 (IN)L -62.4 87.10 good
798 +89.93 +/- 0.73 0 (IN)L -62.4 87.10 good
Moller test summaries
Jan. 30, 2011
Today we adjusted the Moller HV, performed a collimator scan, and took some polarization data. See immediately above for a picture of the tune plot. The hallcp_ ~1159 MeV. The full reports can be found in the following Qweak ELOG entries: Polarization study, Updated collimator values.
The new quad currents and collimator positions are as follows:
Quad 1: 93 A Quad 3: 129 A Col # Position (cm) 1 -1.55 2 -1.55 3 -4.05 4 -4.15 5 Out of beam 6 -3.20 7 -3.20
The overall polarization was 89.38 +/- 0.2621%. The real/random ratio (in kHz/uA): 81.
Run Polarization (%) Comments 702 (-90.07 +- 0.63) New HV L 1510V, R 1535V 703 (-88.75 +- 1.31) New HV L 1510V, R 1535V 704 (-90.48 +- 0.71) New HV L 1510V, R 1535V 705 (-89.84 +- 1.15) Old HV L 1480V, R 1520V tripped at end 706 (-89.31 +- 1.09) Old HV L 1480V, R 1520V tripped at end 707 (-89.46 +- 1.52) junk - Not included in the plot 708 (-89.37 +- 0.78) Old HV L 1480V, R 1520V 709 (-89.92 +- 1.50) HV L 1530V, R 1555V 710 (-88.15 +- 0.72) HV L 1610V, R 1655V 711 (-89.77 +- 0.72) HV L 1610V, R 1655V 712 (-88.08 +- 0.72) HV L 1610V, R 1655V
Jan. 21, 2011
This was our first straight Moller measurement after the holiday down. Only a series of simple measurements were taken at varying currents were taken, no systematic studies. It was also hoped we could use this data to (eventually) calibrate BCM 17. Notice also the backgrounds remain consistent and reproducible from the December measurements.
Conditions: INHWP: In, QE=0.32%, HALLC:p=1159.82 MeV. Collimator 5 was out.
Run Polarization Note 686 -90.46 +/- 0.52 1 uA 687 -91.36 +/- 0.69 1.5 uA 688 -90.60 +/- 0.67 2.0 uA 689 -91.64 +/- 0.99 1.5 uA 690 -88.56 +/- 1.36 0.5 uA - bad beam position 691 -91.28 +/- 1.43 0.5 uA
Excluding run 690, the average polarization is -90.86+/-0.32%.
Spin dances
The initial Qweak Moller spin dance occurred November 23, 2010. Originally scheduled to coincide with Hall A, beam tune issues (on their end only) prevented a joint study.
Test setup: IHWP=OUT, QE=0.35%, Hallc:p 1159.66 MeV +/- 0.03. Solenoid at 3.5T, with 1 um foil. The current was adjusted using the laser attenuator, slit was wide open. Quoted polarizations are from the Dave G. scaler-bank-3-only analysis.
Run Wein Polarization Comments 508 -0.1 40.04 +/- 1.23 200 nA 509 -0.1 40.05 +/- 1.88 1.05 uA 510 -0.1 40.40 +/- 1.03 1 uA 511 -0.1 40.13 +/- 0.68 0.9 uA 512 -0.1 40.19 +/- 0.70 0.9 uA 513 -0.1 40.13 +/- 0.70 0.9 uA 514 -0.1 40.14 +/- 0.65 0.57 uA 515 -0.1 N/A (junk) Hall C laser off - no Hall A bleedthrough 517 +29.0 -2.75 +/- 0.65 0.9 uA 518 +29.0 N/A Hall C laser off 519 +29.0 -3.70 +/- 0.69 0.9 uA 520 +29.0 -3.48 +/- 0.68 0.9 uA 521 -31.0 75.85 +/- 0.88 0.9 uA 522 -31.0 76.81 +/- 0.69 0.9 uA 523 -31.0 75.61 +/- 0.69 0.9 uA 524 -31.0 75.50 +/- 1.25 0.9 uA 525 -31.0 74.54 +/- 0.96 0.9 uA 526 -31.0 75.37 +/- 0.67 0.9 uA 527 -75.0 87.89 +/- 0.70 0.9 uA 528 -75.0 87.63 +/- 0.69 0.9 uA 529 -75.0 86.69 +/- 0.69 0.9 uA 530 -75.0 86.83 +/- 0.79 0.9 uA 531 -63.20 88.64 +/- 0.74 0.9 uA 532 -63.20 89.65 +/- 1.12 0.9 uA 533 -63.20 90.32 +/- 0.69 0.9 uA 534 -63.20 89.51 +/- 0.68 0.9 uA 535 -63.20 89.73 +/- 1.90 0.9 uA 536 -63.20 90.04 +/- 0.91 0.9 uA
The ideal horizontal wein angle was calculated to be -63.2 degrees. The measured polarization value at this wein was 89.62 +/- 0.35 (stat)%. Below the fit of polarization vs. Wein angle.
The original hclog result entries are #208285 and #208394.
Moller Commissioning - Nov. 14, 2010
Initial Moller commissioning was on on November 14th, 2010. Polarizations up to 89% occurred. It consisted mainly from runs 476-490. Several targets, currents, and pre-scales were used. Collimator 5 was also removed for several runs to determine if scraping occurred. The following is a run summary:
Run target current(uA) Camac prescale Polarization (%) Comments 477 1um 0.2 100 89.99+/-0.88 478 1um 0.2 100 88.17+/-0.89 479 1um 1.0 100 NA junk 480 1um 1.0 1000 87.20+/-0.69 481 1um 1.0 1000 88.91+/-0.71 482 4um 0.2 1000 89.05+/-0.77 collimator 5 out 483 4um 0.2 1000 89.61+/-0.80 collimator 5 out 484 no tgt 1.0 1000 NA collimator 5 out 485 no tgt 1.0 1000 NA collimator 5 in 486 1um 0.6 1000 88.68+/-0.80 collimator 5 in 487 1um 0.6 1000 87.95+/-0.82 solenoid at 3.5 T, collimator 5 in 488 1um 0.6 1000 89.12+/-0.90 solenoid at 3.5 T, collimator 5 in 489 1um 0.6 1000 89.69+/-0.80 solenoid at 3.5 T, collimator 5 in, fast raster 2x 490 1um 0.6 1000 89.39+/-0.81 solenoid at 3.5 T, collimator 5 in, fast raster 2x2 491 1um 0.2 1 NA solenoid at 3.5 T, collimator 5 in, fast raster 2x2
Also, here is a screen shot of the moller medm screen. Note the Q1 and Q2 currents, and the location of the collimators. This data may change, but should be accurate for the near term.
