MIF Meeting 2013/2/26

Date/Location

2013/2/26, /SeeVogh

Participants

Aso, Yamamoto, Somiya, Nakano, Takahashi, Akutsu, Shibata

Fast beam shutter

• The first prototype was made at Somiya Lab. by Tobias. The initial test yielded less than 1msec shut down time. (The shutter was 1mm away from the center of the beam)
• Larger separation from the beam center is necessary to avoid scattering by the shutter blade (roughly 1cm). Bigger capacitor is necessary.
• The prototype system exploded and currently it is not usable.
• Cost to make one is less than 10000JPY.
• We need to estimate the maximum amount of power falling onto the PDs.
• Is it possible to just shutting down the beam at the output of the laser.

Vacuum enclosure

• Cosmotec is expensive
• Contact the company making the aLIGO's PD enclosures

Suspension Modeling

• Checked the validity of the methodology by constructing a double pendulum model and comparing it with the hand solved analitic formula. They agreed well.
• Needs better filters to realize true damping.
• Construct a rigid body double-pendulum model next.
• Then construct a Type-B payload only model.

KAGRA de-scoping related

===== Inferior suspension ====

• Length requirement is OK for PRC
• ASC requirement has to be checked

No Green Lock

• Digital Interferometry (Nikhef)

No OMC

• Noise calculation with RF

No BRT

• Not an option. Needs more discussion
• How to extract the transmission beam if there is no iKAGRA ETM chamber.

A/I

• Ask Nishida-san to work on the estimation of the maximum power falling on the PDs using e2e (Somiya)
• Construct rigid body models of suspensions (Nakano)
• Contact the company making the aLIGO's PD enclosures (Akutsu)
• Alignment noise requirement for PRC/SRC mirrors
• RF DARM noise (Aso)
• Further discussion of BRT (Akutsu)