= Output Mode-cleaner =

== Meetings ==
 * [[KAGRA/Subgroups/IOO/OMC/meeting2016|2016]]
 * [[KAGRA/Subgroups/IOO/OMC/meeting2017|2017]]
 * [[KAGRA/Subgroups/IOO/OMC/meeting2018|2018]]

== Installation work ==
 * [[KAGRA/Subgroups/IOO/OMC/installation|2018/10-11]]

== Reports ==

 * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=8043|OMC Design Document]]

 * [[KAGRA/Subgroups/IOO/OMC/DCPDCalculation|DC PD]]

== Requirement ==

Shot noise increase due to the signal reduction by the OMC and residual spatial higher order modes after the OMC should be less than 5%.

== Optical Design (updated 19/8/11) ==
||item||RoC||Beam Raidus||Misc||
||OMMT1||13.16m||4.46mm||Dia: 99.95mm, thick: 55.58(largest), wedge: 2.45deg (measured by Hirose-san 2018)||
||OMMT2||44.39m||2.68mm||Dia: 99.97mm, thick: 55.08(largest), wedge: 3.3deg (measured by Hirose-san 2018)||
||OSTM||flat||TBA||||
||OMC1||flat||444um||||
||OMC2||flat||444um(X)/447um(Y)||||
||OMC3||1.80m||604um||||
||OMC4||1.80m||604um||||
||DCPD||--||592um||||

||Space||Distance||AOI||
||SRM-OMMT1||5.63m||3.07deg||
||OMMT1-OMMT2||2.60m||3.07deg||
||OMMT2-OSTM||2.97m||90deg||
||OSTM-OBS1||0.30m||90deg||
||OBS1-OMC1||0.03m||0.078deg||
||OMC1-OMC2||0.357m||3.00deg||
||OMC2-OMC3||0.359m||3.00deg||
||OMC3-OMC4||0.357m||3.00deg||
||OMC4-OMC1||0.359m||3.00deg||

== Suspension Design ==

||Total mass to be suspended||13kg||
||Number of suspensions||3||
||Blade spring size||220mm x 53mm||
||Radius of curvature||190mm||
||Distance from a blade end to a suspension wire||203.5mm||
||Blade material||MAS-1||
||Blade mass||4.3kg||

 * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=7050|JGW-G1707050-v1]]

== Control Scheme ==

||||LSC||
||Dither frequency||1kHz (tentative)||
||Dither optics||OMC3 or OMC4||
||Signal extraction port||OMC trans DCPDs||
||||ASC||
||Dither frequency||not yet decided||
||Dither optics||OSTM (tentative)||
||Signal extraction port||OMC trans DCPDs; on-board QPDs are used for the course alignment||


== OMC Venting and Repumping Procedure with HPL preparation with PLL (2023/Jan/30~Feb/3) ==

 * (Jan 30, Mon)
  * Before 9:00: FPMI realignment (Yokozawa-kun), Preparation for venting (Kimura-san, M.Takahashi-san), Turning on all FFUs in the OMC area.
  * Keep IMC lock using the present fiber laser. Stanby of R.Takahashi-san and Aso-kun for monitoring.
  * After informing the start of venting from Kimura-san to R. Takahashi-san, Kimura-san starts venting. 
   * If OMMTs realignment with pico is necessary, It will be done.
  * After finishing venting, Kimura-san informs to R.Takahashi-san, Aso-kun, Miyakawa-kun and Miyoki.
  * Miyoki changes the PSL from OBS to Work mode at this time with IMC ASC? or around after all works are done on Jan 30?
   * IP2? HV drift monitoring.
   * Offload of IMC suspensions and IP1/2?
  * (Para)Just after the PSL mode change, Miyakawa-kun starts FB -> HPL changing and IMC control with HPL.
  * (Para)After closing the GV between SRM/SR2, Kimura-san starts opening the bellows at GV. So no laser to OMC area. Kimura-san starts the repair work. We would like to avoid removing the all bellows duct to reduce the risk to produce another leak on the healthy opposite side.

 * (Jan 31, Tue)
   * Kimura-san dose repair work and closes again. Also, after checking no problem happens in the vacuum level in SRM, the GV between SRM/SR2 is opened. Check the IR beam to and from OMC by ??.
   * Recover the operated FFU number in OMC as before this wrok.
   * After this work, R.Takahashi-san dose health check for OMC suspensions in this day or tomorrow morning
   * Miyakawa-kun PLL control adjustment with Izumi-kun. Sometimes, IMC unlock is expected?
    * The GR frequency will be kept, while the HPL IR frequency will be adjusted by changing the crystal temp.

 * (Feb 1, Wed)
  * Morning
   * Miyakawa-kun's HPL works.
  * Noontime
   * From 13:00?, Kimura-san informs R. Takahashi-san and Aso-kun about the start of pumping. The Kimura-san starts pumping gradually.
    * If OMMTs realignment with pico is necessary, It will be done.


 * (Feb 2, Thu)
  * Miyakawa-kun change the HPL to FB again? After this or earlier timing, the PSL room should be set to OBS mode again.(Or should we do in the week end holidays?)
  * Kimura-san/Yasui-san start the vacuum leak check. If no leak is verified, we will decide when we can open the GV, judging from the vacuum level reduction speed.
   * Opening GV might result in the realignment of the IF beam to OMC.

 * (Feb 3, Fri)
  * DGS maintenance day.

== OMC Blade Damping (2023/June/22) ==
 * Somiya-kun's Presentation
 *