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    User name Saha

    Log entry time 11:25:16 on February 8,2000

    Entry number 33131

    keyword=E89044 - Beam Related Checks and Record during Shift

    E89044 - Beam Related Checks and Record during Shift
    ____________________________________________________

    In every shift Hall A personnel should pay attention to the following items:

    1. Fast Feedback operational for Hall A.
    _________________________________

    Make sure that FFB is running in ABSOLUTE mode for both POSITION and ENERGY for Hall A. This verifies that the beam position and optics are stable.

    Go to the Accelerator Main Menu (monticello.adl) screen. Click Hall A and then click on Hall A General Info. The fast Feedback information is on the left hand bottom corner (under the Beam Position on Target screen).

    If there is any doubt, verify from MCC. Call Run coordinator if FFB is not ON.
    DO NOT accept beam for data taking unless this is operational.
    You will be held responsible if it is not on and you accept beam.

    2. OTR screen for beam energy width
    _______________________________

    IMPORTANT NOTE: DO NOT click or change anything on the OTR screen.

    Go to the Accelerator Main Menu (monticello.adl) screen. Click Data Acq. Click on [Datacube OTR and Synch Light Setup]. In this screen, the source should be set for Hall A (If not, request MCC to put source to Hall A and set the proper standard default settings for Hall A). If the settings are right, you should get narrow beam profiles for x and y profiles. If the screen is calibrated (ONLY by MCC), the parameter to monitor is the Calibrated x width (in mm).

    This number reflects the energy width of the beam.
    The OTR is located at the 1C12 location of the Hall A arc which, in achromatic tune, is the point of high dispersion in the arc : Dispersion = 4 m
    For a width of 0.200 mm, reflects a energy width of 5 x 10^[-5].
    This is the acceptable limit for our experiment (e89044).
    There should be a stripchart [beam-energy-width] monitoring this width.
    If the width is significantly > 0.200 mm, inform MCC and see if it is just a bad calibration or setup.
    If the width is really > 0.2 mm, MCC needs to make it smaller.

    3. Harp scans of scanners (#5,#6) before the target [Record: once/shift]
    ____________________________________________________________

    IMPORTANT NOTE: DO NOT run Harp Scans above 5 uA cw.
    Instructions to run Harp scans are in the Experimental web page.

    With Raster OFF, Record both beam position and intrinsic width of the beam.
    After analyzing the harp scan data, log and enter (in halog):
    (1) Beam positions at scanner locations #5 and #6 with BPM readings.
    BPM: 3Ax 3Ay 3Bx 3By
    Scanners: #5x #5y #6x #6y
    (2) Width of beam profile at scanner #6 location [Both Sigma_x, Sigma_y].

    With Raster ON, monitor beam size with "Spot" and compare with harp widths.


    4. Stripcharts [Record: Every 4 hrs]
    _______________________________

    Record in halog the beam related Strip Chart [/home/hacuser/E89044_beam].
    Make sure all the parameters are within acceptable limits.

    In the main HAC_xt medm screen, click on Strip Chart and then on NEW StripTool. A StripTool Dialog Box will appear. Click on File and then on Load Configuration. A Configuration File_popup screen will appear. Click on file "E89044_beam" and load on to the stripchart.
    This stripchart contains the following informations:

    hac_bcm_average [blue] - The average beam current from the two BCMs
    IPM1H03B.XPOS [red] - The absolute x position at BPM 3B (< 0.25 mm)
    IPM1H03B.YPOS [grey] - The absolute y position at BPM 3B (< 0.25 mm)
    halla_MeV [orange] - The MCC beam energy corrected for orbit changes
    MV_AI_DXWID [green] - The OTR horizontal width (< 0.2 mm, see note 2 above)

    You should also record (as stripchart) any variable separately if the information gets too crowded in the main beam stripchart.
    Remember: we should all be able to see this information for future use.