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    User name Yi Qiang

    Log entry time 22:03:45 on April 28, 2009

    Entry number 269546

    This entry is a followup to: 267977

    Followups:

    keyword=EPR calibration for Vertical pumping

    Bothered by very very high polarization, i did the following EPR
    calibration with extreme cautious: I leave the NMR RF off when not in flip.
    1. I first did a FM sweep from 10 MHz to 21 MHz: the signal below 11MHz
    is most likely cable resonance, the signal at 11.5MHz is Rb EPR peak, the
    signal at 14.5 is an isotope signal and the signal at 15.5 MHz is the K
    EPR peak.
    2. The first EPR calibration is done with the K signal.
    3. The second EPR calibration is done with the Rb signal.
    As a result, the two calibrations from different alkali atoms are quite
    different! The K gives a constant of 3.875%/mV while the Rb only gives
    3.441 %/mV. Obviously, we have something wrong in the EPR analysis code
    and I will try to find it out.

    Here are the data details:

    Cell: Dominic
    Oven Temperature: 230C
    Field Direction: Vertical -
    Pumping Direction: Parallel
    Laser Power: 3x25 COMET
    Cell Density: 7.830 amg

    == EPR of K ==
    Data directory: C:\AyeD\EPR\Data\EPR_AFP_20090428_2122
    Calibration Constant: 3.87 %/mV
    Polarization: 86.79%
    Field: 24.841 G
    EPR Frequency Shift: 98.38 kHz

    == EPR of Rb ==
    Data directory: C:\AyeD\EPR\Data\EPR_AFP_20090428_2138
    Calibration Constant: 3.87%/mV
    Polarization: 75.74%
    Field: 24.830 G
    EPR Frequency Shift: 73.45 kHz

    A copy of this log entry has been emailed to: jpchen, tdaver@wm.edu, yqiang, chiran, jinhuang



    Whole range EPR FM sweep



    EPR FM of K



    EPR AFP of K



    EPR Analysis of K



    EPR FM of Rb



    EPR AFP of Rb



    EPR Analysis of Rb