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    IR1 corrections and updates from other IRs

    → Europe/Zurich
    6/R-012 - conference room (CERN)

    6/R-012 - conference room

    CERN

    40
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    Carolina - IR1/7/8 Corrections

    Carolina showed SbS plots before and after corrections for the measurements from 11th of May,
    for the 1m optics.
    IR7, mainly vertical Beam1 and horizontal Beam2 confirm the correction
    IR8, similar correction performance

    In conclusion (partial) confirmation of the corrections in IR7/8

    Corrections from Action and Phase method were shown for IR1.
    Consistent with triplet corrections as computed with SbS 

    Ewen - IR1 corrections

    Ewen presented IR1 corrections for 40cm and 2m optics

    Triplet strengths have the same tendency as the ones shown by Carolina.
    Corrections for 40cm use one triplet right and one left of the IP.
    Using kq6.l1 for Beam1 helps to improve the corrections

    Also for 2m adding kq6.l1 helps to have a better correction.
    Rogelio comments that it is not cleat, and difficult to judge based on the measurement data.

    kq6.l1 for Beam2 is not obvious if it improves the correction, furthermore, the sign would need to change
    except if the triplet corrections are slightly increased.
    It was concluded not to include kq6 for Beam2

    Andy - IR1 corrections

    Situation similar to 40cm/2m

    Not including B1 kq6 gives a too small amplitude in one plane - adding kq6 looks better for the downstream, but the initial slope following the KQ6 looks to have the wrong sign. Hard to conclude about the KQ6. Maybe just leave the KQ6 for the global correction, but seem to have confirmed the triplet errors. 

    From these results could start putting triplet correction in at 7m, and leave the KQ6

    Lucas - IR1 corrections

    Lucas computed corrections using all 3 triplets in SbS.
    Corrections contain Q1 and Q3 right of IP1

    The corrected phase was compared for 1m/2m/7m, showing a reasonable correction, comparable to the one using the Q2s.
    7m B1 horizontal suggests slight preference to use corrections in Q2,
    although the difference is very very different.

    The correction should be tested also for 40cm to determine which one should be used.
    Further test could be to use 1m measurement before correction.

    Ana - IR2 

    Ana showed phase deviation plots for IR2 before and after corrections.
    The corrections seem to be very small.

    2m horizontal shows slight improvement.

    For 40cm after correction also includes MQT corrections, and the phase deviation 
    in this case looks slightly worse.

    40cm should be checked without MQT correction

    Jaime - Software updates

    Hovering over the model in the GUI, shows model information.

    New button for falling back to 3-BPM method when running get optics

    To be checked if WAnalysis uses new or old algorithms for beta --> Andy

    SVD clean time performance is different if you call from python or Java.
    It is just using one core in both cases.

    Confirm with Thomas if SVD was written to run in parallel, or what could be the reason why it does not anymore --> Jaime

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