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dan.chen - 15:13 Wednesday 02 July 2025 (34436)

Violin mode Q estimation

We analyzed the violin mode peaks using approximately 6000 seconds of data starting from GPS time 1433982518 (2025-06-15).

For the 1st, 2nd, and 3rd violin mode frequency regions, peaks were searched and fitted individually. The fitting results are attached.
During visual inspection of the fitting results, obviously incorrect fittings were marked with “X.”
Most of the fitted peaks show Q factors around 1e5. In the 1st mode region, there are three peaks with significantly higher Q values (they look too high...), which are currently under investigation.
The mirror temperatures at the time of measurement were as follows:
- Temperature [K]: (IX, EX, IY, EY) = (92, 49, 42, 58)
A PDF showing each fitting result is also attached.

Images attached to this report

Comments to this report:

dan.chen - 6:41 Thursday 03 July 2025 (34438)

PDF showing each fitting: https://www.dropbox.com/scl/fi/h87b1kxmtvxrobqcc8f35/each_fit.pdf?rlkey=xtrz5wmwzb5t0a5zfgih8tmb0&st=579p0hzm&dl=0

dan.chen - 14:57 Thursday 03 July 2025 (34446)

The PDF file was updated: https://www.dropbox.com/scl/fi/h87b1kxmtvxrobqcc8f35/each_fit.pdf?rlkey=xtrz5wmwzb5t0a5zfgih8tmb0&st=p15q49za&dl=0
I changed plot styles.

dan.chen - 15:03 Thursday 03 July 2025 (34447)

According to klog32643, the peaks got the very high Q values seem to be violin mode:

Peak of 1st No.2: "EYIMP"
Peak of 1st No.6: "IYIMP"
Peak of 1st No.9: "EXIMP"

dan.chen - 5:18 Friday 04 July 2025 (34451)

After checking the updated PDF, it seems that all three peaks in question (1st No.2, No.6, and No.9) have issues in the fitting results. I plan to adjust the settings to use a longer FFT length and reanalyze them.