Installation Acceptance Document for MCF and MCE in spring 2021
JGW-Exxxxxx
Date: 22 April 2021
Scope
Provide short descriptions to define the scope of this acceptance review, and fill the items.
This document covers the technical content for acceptance review of installing the input mode cleaner(IMC) and its relevant equipments in the MCF and MCE chambers before sealing them.
Vacuum chambers
MCF, MCE
Electronics rack
xxx
Optics tables/rooms
PSL, IMC_REFL, MCE_TRANS
Context
Provide detailed explanations of the context or background of the installation activities covered in this acceptance review.
From the results of O3GK and the following RSE challenge, we learned that we needed to mature several subsystems of the KAGRA interferometer in a secular way for improving its sensitivity. For the input optical system, beam pointing control is to be improved, and beam jitter is to be mitigated. Besides, stray light around IMC seemed to contribute noise in O3GK. Foreseeing O4 and O5, we also account for introducing a high-power laser source. Therefore we need to mitigate the stray light from the viewpoint of not only performance but also safety.
Taking all into account, we will re-visit the scheme of alignment sensing and control(ASC) for the input optics including IMC. That requires us to characterize those inside MCF and MCE like IMC suspensions(mirrors: MCi, MCo, and MCe) and regarding light beams. Additional beam dumps and safety shields should be installed in these chambers. Therefore we have vented these chambers, unsealed several of the flanges, and worked inside.
Before sealing the flanges again, we need to check whether we have completed what we wanted to do. Although these chambers will open again in this summer, it would be better to check those seriously here.
Procedures
Enter a link to the relevant part of the schedule, and then provide a comparison table by entering references for planned installation procedures(e.g. JGWdoc) and the actual work logs(e.g klog, slack, or wiki).
Redmine
See the redmine here. Category: IOO-input, from Feb 2021 to May 2021. Task#40 and #51.
Comparison table
Hmm… listing here is not useful. Next time a link to the spreadsheet.
Task#
Description
Planned installation procedures
Work logs
598
Align the input beam from PSL with IP2 to the designed position on STM1 in IFI
Scope
Context
Procedures
Redmine
Comparison table
Drawings
Serial number records