Differences between revisions 2 and 3
Revision 2 as of 2013-07-23 12:41:50
Size: 2289
Editor: YoichiAso
Comment:
Revision 3 as of 2013-07-23 14:41:21
Size: 2297
Editor: YoichiAso
Comment:
Deletions are marked like this. Additions are marked like this.
Line 1: Line 1:
Participants: Yamamoto, Miyakawa, Somiya, Akutsu, Ueda, Takahashi, Sekiguchi, Michimura, Aso Participants: Yamamoto, Miyakawa, Nakano, Somiya, Akutsu, Ueda, Takahashi, Sekiguchi, Michimura, Aso

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)

KAGRA/subgroup/ifo/MIF/Minutes20130722 (last edited 2013-07-23 14:41:21 by YoichiAso)