HOME SBOX THOMX MINICAV Utilities
SBOX orders SBOX installation SBOX commissioning SBOX control command
  Status of commissioning, report also here plots are reports.  Not logged in ELOG logo
Entry   new cavity, posted by Alice Renaux at Optical room about lasers and optics 
    Reply   new cavity, posted by Alice Renaux at Optical room about lasers and optics Finesse.png
Message ID: 245     Entry time: Wed Sep 10 11:27:45 2025     In reply to: 244
 Author: Alice Renaux 
 Status: Under Process 
 Type: report 
 Category: lasers and optics 
 Location: Optical room 
 Title: new cavity 

The 2-mirrors cavity has 460ppm of transmission for M1 and 10ppm for M2 which should exhibit a Finesse around 13400.

Today, we managed to lock the NKT laser (with an AOM for fast feedback) onto the cavity, and we made 5 Finesse measurements with the modulation technic : 14151, 13847, 13968, 14604, 13892 with an average around 14000 => LW = 216MHz/F ~ 16kHz.

On the plot (Frequency span 1MHz <=> Time span 10s)
blue curve : raw data
black curve : cleaned data
red curve : fitted data

Alice Renaux wrote:

Yesterday, we changed the M1 mirror to a 161185 Gamma Factory mirror of transmission 460ppm, the cavity finesse is now 13360.

We managed to lock it today.

 

Attachment 1: Finesse.png  26 kB  | Hide | Hide all
Finesse.png
ELOG V3.1.4-395e101