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Message ID: 7410     Entry time: Wed Sep 19 13:12:48 2012
Author: Jenne 
Type: Update 
Category: IOO 
Subject: Power into vacuum increased to 75mW 

The power buildup in the MC is ~400, so 100mW of incident power would give about 40W circulating in the mode cleaner.

Rana points out that the ATF had a 35W beam running around the table in air, with a much smaller spot size than our MC has, so 40W should be totally fine in terms of coating damage.

I have therefore increased the power into the vacuum envelope to ~75mW.  The MC REFL PD should be totally fine up to ~100mW, so 75mW is plenty low.  The MC transmission is now a little over 1000 counts.  I have changed the low power mcup script to not bring the VCO gain all the way up to 31dB anymore.  Now it seems happy with a VCO gain of 15dB (which is the same as normal power).

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