Participants: Yamamoto, Miyakawa, Nakano, Somiya, Akutsu, Ueda, Takahashi, Sekiguchi, Michimura, Aso

Current Status
 * Ask Izumi-kun, the status of green lock at LIGO.
 * Back up plan for lock acquisition (in case green does not fly) is necessary.
  - Transmission power offset lock
  - Digital Interferometry ?
 * KAGRA CDS for Interferometer Control will be developed at Kamioka. 
  - Will allow remote access to the system for remote development
  - Improve the CLIO CDS to be a prototype of KAGRA CDS
 * Installation planning has to be started immediately
  - How to precisely locate and align mirrors ?
  - List up necessary vacuum feedthrough
  - Prepae rack wiring diagrams
 * Vacuum Enclosure
  - Find better companies in Japan. Work with VIS.
 * Beam Handling in Vacuum
  - Building an integrated CAD model of the vacuum chamber and suspensions to properly arrange beam damps and so on.
 * OMC
  - Better calculation of HOMs with realistic phase maps of the mirrors.

Beam Shutter Development (by Ueda)

 * A fast beam shutter prototype with HDD motor was made.
 * 1.5msec to move 1.5mm. 1.8msec for 5mm.
 * E2E simulation for deposited power on PDs when lock is lost (about 3W at AS)
 * PD damage threshold ~ 100mJ ?
 * Open questions:
  - Where to put the shutter. Before or after the OMC ?
  - Scattered light noise by the shutter blade.
  - Black coating on the blade ?

Suspension modeling with active damping (By Sekiguchi, Nakano)

 * A pre-isolator model with active damping using LVDT and GEOPhone was made
 * Calculations were also done for full Type-A and Type-B cases.
 * Sensor noise is a serious problem in all the cases.

Requirements for vibration of in-air optics

 * Beam jitter and scattered light noise should be considered.
 * For actual purchase of optics mounts, we should select the shortest possibe ones.


Action Items
 
 * Get more information on the green lock status in LIGO (Aso)
 * Installation planning (Aso)
 * Find a good company to make vacuum PD enclosures (Akutsu)
 * Continue the beam shutter study (Ueda)
 * Continue the active damping study (Sekiguchi, Nakano)
 * Vibration level requirements for in-air optics (Nakano)
 * Ask Telada-san to make a list of small optical components to buy (Aso)