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Entry  Sat Jul 30 00:33:33 2011, Koji, Update, PSL, ABSL Laser crystal temp left largely excited & left unattended for more than 3hours 
    Reply  Sat Jul 30 02:47:43 2011, rana, Update, PSL, ABSL Laser crystal temp left largely excited & left unattended for more than 3hours 
Message ID: 5064     Entry time: Sat Jul 30 00:33:33 2011     Reply to this: 5065
Author: Koji 
Type: Update 
Category: PSL 
Subject: ABSL Laser crystal temp left largely excited & left unattended for more than 3hours 

I found that the ref cav trans CCD view was blinking with 30-50 fringe amplitudes. This meant the laser freq was swinging ~50GHz.

I checked the ABSL laser and the SG out of a lock-in amplifier was connected to the slow input.

This was shaking the laser temp from 29degC to 46degC. This was the cause of the fringe swinging.
This big excitation changing the output power too as the temp was changed across it mode-hop region.

I have disconnected the excitation from the laser no matter how useful experiments were took place as there was no e-log entry about this.

I need the explanations

1. Why our precious laser is exposed to such a large swing of temperature?

2. Why the excitation is left like that without any attendance?

3. Why there was no elogging about this activity?

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