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Entry  Thu Mar 7 12:39:12 2013, Jenne, Update, Locking, Erudite discussion on PRMI locking 
    Reply  Thu Mar 7 16:55:28 2013, Koji, Update, Locking, Erudite discussion on PRMI locking 
    Reply  Tue Mar 26 00:17:47 2013, Jenne, Update, Locking, REFL pickoff fraction 
    Reply  Tue Mar 26 11:08:03 2013, Jenne, Update, Locking, PRMI locking should be possible - let's get it done! PRMI_SBres_plot_allTheFs_LowRes.pngLSC_sigmatrix_PRMI.pdf
Message ID: 8351     Entry time: Tue Mar 26 11:08:03 2013     In reply to: 8250
Author: Jenne 
Type: Update 
Category: Locking 
Subject: PRMI locking should be possible - let's get it done! 

[Jenne, Gabriele, Jamie]

We have looked at Koji's old Finesse code, and determined that the PRMI sensing matrix that he calculated was for the sideband-resonant case.  Thus, this is the sensing matrix we are interested in for locking. Gabriele has confirmed this using independently written code with his software, Mist.

Pics or it didn't happen:

 PRMI_SBres_plot_allTheFs_LowRes.png

The sensing matrix is:

LSC_sigmatrix_PRMI.pdf

Numerical values are on the wiki:  https://wiki-40m.ligo.caltech.edu/IFO_Modeling/SensingMatrix

For any of the REFL PDs (1*f1, 1*f2, 3*f1, 3*f2), the PRCL signal is a factor of ~100 larger than the MICH signal.  Rana assures us that, with some clever triggering, we should be able to lock the PRMI. 

This means that we will not be venting in the next few days to flip the SRC folding mirror.  We will work on PRMI lock (probably first with 1*f, but then quickly moving on to 3*f), and as soon as Annalisa and Manasa have the new ETMY table ready for us, we will then do PRFPMI.  (We can also play with the Xarm green until Yarm green is back).

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