Abstract:

I developed the sript to find TEM00 of GRX during initial alignment.
The script seems working well, so we can use it if GRX cannot be locked during initial alignment.

Detail:

Since initial alignment is done once a week currently, GRX lock is sometimes difficult.
So, I developed the script to find the GRX TEM00 for initial alignment.

Followings are the procedure:
1. MISALIGN ETMX
2. Scan PR3 (scan area is +/- 30urad from the current position).
3. Align PR3 at thecenter of transmitted PD.
4. ALIGN ETMX again.
5. Sweep IXP, IXY, EXP, and EXY with dfferent frequency and find the values when GRX is maximum.
6. ALIGN ITMX and ETMX to good OpLev value.

After finishing the script, GRX can be locked with TEM00, so we can perform usual initial alignment procedure.

How to use:

1. Confirm initial alignment guardian cannot lock GRX with TEM00 by requesting GRX_LOCKED state to INITIAL_ALIGNMENT guardian.
2. Request DOWN state to the guardian.
3. Open terminal.
4. Run the scripts by  pressing the command "python3 /users/ushiba/script/python/search_GRX_alignment.py"
5. Wait until finishing the script: showing "End" on the terminal. It takes about 4 minutes.