Difference between revisions of "Moller Polarimeter/NPS"

From PolWiki
Jump to navigationJump to search
Line 1: Line 1:
 
==Summary Plot of NPS Moller Measurements==
 
==Summary Plot of NPS Moller Measurements==
  
[[File:Nps_pol_27oct2023.png]]
+
[[File:Nps_pol_6nov2023.png]]
  
 
==Moller measurement summaries==
 
==Moller measurement summaries==

Revision as of 16:43, 6 November 2023

Summary Plot of NPS Moller Measurements

Nps pol 6nov2023.png

Moller measurement summaries

Note that this is the first experiment to use the new cryogen-free superconducting target magnet.

September 22, 2023

  • IHWP IN: P = -80.06 +/- 0.54 %
  • IHWP OUT: P = 80.55 +/- 0.58 %
  • Tune up at 5 pass. Had a hard time seeing scintillators - thought they were gain matched ok (but maybe they weren't), so thought there might be problems with DAQ.
    • Q1 = 126.86 A
    • Q2/Q3 = -1318.0 A
    • Final collimator settings: https://logbooks.jlab.org/entry/4185462, NOTE: these are wrong - chose wrong collimator 3 setting!
      • 1/2 = -0.60/-0.60
      • 3/4 = -1.80/-2.40
      • 5=0.0
      • 6/7=-2.90/-2.80
Run	  Pol (%)   Error (%)	Hwien     HALC:p(MeV)     Comment
1787      -         -           -48.3     -               First run after gain matching calorimeters, 1 um foil
1788      -         -           -48.3     -               Changed ADC/TDC prescale
1789      -         -           -48.3     -               All scintillators turned on
1790      -         -           -48.3     -               Q3 reduced from 1338 to 1318 A
1791      -         -           -48.3     -               Changed memory delay from 4->3
1792      -         -           -48.3     -               Changed memory delay from 3->5
1793      -         -           -48.3     -               junk
1794      -         -           -48.3     -               After rebooting all
1795      -         -           -48.3     -               Added delay to memory strobe (16 ns, 8 ns)
1796      -         -           -48.3     -               Changed defaults in CRL
1797      -         -           -48.3     -               Set memory delay to 7 (WSI was unplugged - woops)
1798      -         -           -48.3     -               Delay=7
1799      -         -           -48.3     -               Delay=3
1800      -         -           -48.3     -               Delay=2
1801      -         -           -48.3     -               Delay=4, 4 um target
1802      -         -           -48.3     -               changed prescale, before collimator scan
1803     -79.93     0.77        -48.3     10539.04        IHWP=IN
1804     -80.18     0.77        -48.3     10538.97        IHWP=IN
1805      80.18     0.82        -48.3     10538.83        IHWP=OUT
1806      78.62     2.84        -48.3     10539.53        IHWP=OUT
1807      81.13     0.86        -48.3     10539.14        IHWP=OUT

October 8, 2023

  • IHWP IN: P = -81.03 +/- 0.54 %
  • IHWP OUT: P = 81.21 +/- 0.57 %
  • Attempted to improve gain matching scintillators. Performed short Q2/Q3 scan (rates). Accidentally used wrong collimator positions:
    • 1/2=-1.7 cm
    • 3/4=-2.5 cm
    • 7/8=-2.4 cm
  • Summary log entry: https://logbooks.jlab.org/entry/4195556
  • Runs on 10/8/2023 (QE=0.2791%)
Run	  Pol (%)   Error (%)	Hwien     HALC:p(MeV)     Comment
1823      -         -           -48.3     -               DAQ test
1824      -         -           -48.3     -               Gain matched Left-5 triggered on coins, then used scin trigger for others
1825      -         -           -48.3     -               Increased all scintillator HV 50 V - looks a little better
1826      -         -           -48.3     -               Increased L4 and L9 even more. 1st point of Q3 (=1318 A)scan (4.7 kHz/uA)
1827      -         -           -48.3     -               Q3 scan: 1298 A (4.7 kHz/uA)
1828      -         -           -48.3     -               Q3 scan: 1278 A (4.5 kHz/uA)
1829      -         -           -48.3     -               Q3 scan: 1338 A (4.5 kHz/uA)
1830      -         -           -48.3     -               Q3 scan: 1318 A (4.7 kHz/uA)
1831     -81.33     0.77        -48.3     10538.73        IHWP=IN
1832     -80.73     0.77        -48.3     10538.69        IHWP=IN
1833      -         -           -48.3     -               IHWP=OUT (junk - Hall A performing NMR)
1834      81.53     1.51        -48.3     10538.66        IHWP=OUT helicity error - only got part of run
1835      81.25     0.78        -48.3     10538.71        IHWP=OUT
1836      81.00     1.00        -48.3     10538.71        IHWP=OUT
1837      -         -           -48.3     -               Bleed-thru run (laser off) coin rate=1 Hz

October 17, 2023

  • IHWP IN: P = -80.34 +/- 0.52 %
  • IHWP OUT: P = 80.92 +/- 0.53 %
  • Had HV troubles at beginning - had to load in backup from A1n. Found the scintillators had been set at very voltages. Finally saw good tune plot.
  • Did another collimator scan
    • 1/2 = -1.0/-1.0
    • 3/4 = -2.4/-2.4
    • 6/7 = -2.6/-2.4
  • Summary log entry: https://logbooks.jlab.org/entry/4201825
  • Runs on 10/17/2023 (QE = 0.2563%)
Run	  Pol (%)   Error (%)	Hwien     HALC:p(MeV)     Comment
1839      -         -           -48.3     -               DAQ test
1840      -         -           -48.3     -               Tune plot run
1841     -80.43     0.73        -48.3     10537.67        IHWP=IN
1842     -80.15     0.75        -48.3     10537.72        IHWP=IN
1843     -83.04     3.72        -48.3     10537.69        IHWP=IN, Helicity error
1844      81.64     0.75        -48.3     10537.84        IHWP=OUT
1845      80.20     0.75        -48.3     10537.74        IHWP=OUT
1846      81.78     2.17        -48.3     10537.70        IHWP=OUT

October 27, 2023

  • IHWP IN: P = -80.58 +/- 0.53 %
  • IHWP OUT: P = 80.71 +/- 0.58 %
Run	  Pol (%)   Error (%)	Hwien     HALC:p(MeV)     Comment
1847      -         -           -48.3     -               DAQ test
1848      -         -           -48.3     -               Tune plot run
1849      80.27     0.76        -48.3     10537.80        IHWP=OUT
1850      81.21     0.81        -48.3     10537.63        IHWP=OUT
1851     -81.52     0.74        -48.3     10537.69        IHWP=IN
1852     -79.61     0.75        -48.3     10537.72        IHWP=IN
1853      -         -           -48.3     -               Bleed thru: 0.5-3 Hz (4.6 kHz signal)

November 6, 2023

  • IHWP IN: P = -78.53 +/- 0.55 %
  • IHWP OUT: P = 78.45 +/- 55 %
  • No scans or systematic checks - just measurement. New Wien angle!!
  • Summary log entry:
  • Runs on 11/6/2023 (QE = 0.172%)
Run	  Pol (%)   Error (%)	Hwien     HALC:p(MeV)     Comment
1856      -         -           -15.3     -               Tune plot run
1857      -         -           -15.3     -               junk
1858      -         -           -15.3     -               junk - beam needed to be resteered
1859     -79.37     0.80        -15.3     10539.66        IHWP=IN
1860     -77.80     0.75        -15.3     10539.62        IHWP=IN
1861      78.00     0.78        -15.3     10539.62        IHWP=OUT
1862      78.88     0.77        -15.3     10537.72        IHWP=OUT