40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
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Entry  Tue May 3 21:05:23 2022, yuta, Update, BHD, AS path alignment, removing a lot of green stuff 7x
    Reply  Wed May 4 13:09:42 2022, Anchal, Update, BHD, IMC table balanced again, IMC is locking, YARM is locking 
       Reply  Wed May 4 15:08:59 2022, Tega, Update, BHD, XARM alignment to get flashing IFO_XY_ARMS_Flashing.png
          Reply  Wed May 4 18:52:43 2022, Tega, Update, BHD, POP beam too high at POP SM4 on the ITMX chamber snnp_pr2_pr3_itmy_aligment.png
             Reply  Thu May 5 14:46:22 2022, Anchal, Update, BHD, POP beam height lowered, POP_SM4 raised 
                Reply  Thu May 5 17:05:31 2022, Tega, Update, BHD, IMC & X/Y-arm alignment IFO_aligment_Y_locking_on.png
                Reply  Mon May 9 18:43:03 2022, Anchal, Update, BHD, ITMX table layout corrected 
                   Reply  Mon May 9 18:49:05 2022, Tega, Update, BHD, Relocate green TRX and TRY PDs/cams/optics from PSL table to BS table IMG_20220509_184439943.jpgIMG_20220509_184154722.jpg
                      Reply  Tue May 10 15:46:38 2022, JC, Update, BHD, Relocate green TRX and TRY components from PSL table to BS table IMG_0741.jpegIMG_0753.jpeg
                         Reply  Tue May 10 18:25:43 2022, Paco, Update, BHD, Green Transmission path 
                   Reply  Tue May 10 16:31:14 2022, Tega, Update, BHD, ITMX optlev return beam steered to QPD 
       Reply  Fri May 6 13:48:34 2022, Anchal, Update, BHD, WFS loop instability fixed 
    Reply  Thu May 12 19:55:01 2022, Tega, Update, BHD, AS path alignment AS.JPGOMCchamber.JPG
       Reply  Thu May 12 20:11:18 2022, Anchal, Update, BHD, BHDBS Output beams steered out to ITMY table signal-2022-05-12-201844.jpeg
          Reply  Thu May 12 20:24:29 2022, yuta, Update, BHD, POX and POY investigation POY.JPG
       Reply  Mon May 16 13:22:59 2022, yuta, Update, BHD, REFL and AS paths aligned at AP table REFLPOP.JPGPOPAS.JPG
          Reply  Mon May 16 19:14:17 2022, Anchal, Update, BHD, Camera set on AS path and BHDBS output path 
             Reply  Tue May 17 18:43:38 2022, Anchal, Update, BHD, Placed SRM in ITMY Chamber 
                Reply  Wed May 18 08:30:29 2022, Paco, Update, BHD, SRM OpLev 
                   Reply  Thu May 19 08:51:40 2022, Paco, Update, BHD, SRM OpLev 
                Reply  Wed May 18 09:02:52 2022, Anchal, Update, BHD, WFS1 PD centered 
                Reply  Wed May 18 17:23:15 2022, Anchal, Update, BHD, Placed PRM in BS Chamber 
                   Reply  Thu May 19 18:56:08 2022, yuta, Update, BHD, Current OSEM sensor values with all the suspensions aligned OSEMS.txt
                   Reply  Thu May 19 19:05:59 2022, Anchal, Update, BHD, BS Chamber all work finished, BHD path setup 
                      Reply  Fri May 20 20:03:48 2022, Paco, Update, BHD, ITMY chamber work finished - LO and AS overlapped Screenshot_2022-05-20_20-38-25.pngOSEMs.txt
                         Reply  Mon May 23 13:16:59 2022, Paco, Update, BHD, End of vent - checks OSEMs20220523.txtScreenshot_2022-05-23_13-24-06_IFOaligned_GTRY_still_clipping_but_less.pngPR3position.JPG
                            Reply  Tue May 24 15:21:13 2022, Anchal, Update, BHD, Freeswing tests of new SOS started 
Message ID: 16868     Entry time: Fri May 20 20:03:48 2022     In reply to: 16866     Reply to this: 16869
Author: Paco 
Type: Update 
Category: BHD 
Subject: ITMY chamber work finished - LO and AS overlapped 

[Paco, Anchal, Yuta]

Today, in short we:

  • Recovered alignment of arm cavities, PRC (only ITMX aligned), and then altogether with SRM and PRM aligned to maximize all DCPD levels (AS, POP, REFL, TRX, TRY), but SRC was not flashing and the SRM yaw alignment slider was around its max value, so after recording beam positions on cameras Anchal went into the BS chamber and helped steer the SRC alignment using a combination of SRM, SR2 and AS1. After this every beam was nominally aligned except for LO and AS, which remained to be mode matched.
  • Mode matched LO3-LO4 by hand -- cheeky -- from the ITMY chamber, the final separation between these two mirrors grew by almost 3 inches with respect to the design (!!!) but the LO and AS beams came out nicely. The canonical path used for the steering was LO path, and then we overlapped the beams with the help of a gige basler camera and a couple of DCPDs (Thorlabs).
  • Yuta and Paco started running final checks in preparation for Monday (pumpdown). We aligned the IFO, but noted that using Restore/Misalign sometimes results in hysteresis.. so it is not very reliable for fine alignment modes. Then we optimized DC levels, centered all oplevs, and tweaked Green input alignment on XARM and YARM. The XARM was maximized, but in YARM we could still not get high TEM-00 flashing ...
    • Unfortunately, we discovered a slight clipping of the GTRY beam through PR3 which could mean the current alignment (pointing) is not hitting PR3 center optimally.
  • Attached are the screenshot of current aligned state after the work tonight, with oplevs centered, and the OSEM sensor values.

Attachment 1: Screenshot_2022-05-20_20-38-25.png  363 kB  Uploaded Fri May 20 21:40:46 2022  | Hide | Hide all
Screenshot_2022-05-20_20-38-25.png
Attachment 2: OSEMs.txt  2 kB  Uploaded Fri May 20 21:40:56 2022  | Hide | Hide all
2022-05-20 20:39:15.780409
 =====BS=====
C1:SUS-BS_ULSEN_OUT16 =   599 
C1:SUS-BS_LLSEN_OUT16 =   575 
C1:SUS-BS_URSEN_OUT16 =   602 
C1:SUS-BS_LRSEN_OUT16 =   636 
C1:SUS-BS_SDSEN_OUT16 =   669 
 =====ITMX=====
C1:SUS-ITMX_ULSEN_OUT16 =   403 
C1:SUS-ITMX_LLSEN_OUT16 =   609 
... 76 more lines ...
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