Reports until 20:20, Saturday 12 July 2025
H1 SUS (SUS)
ryan.crouch@LIGO.ORG - posted 20:20, Saturday 12 July 2025 (85715)
Second harmonic violin modes

I took some high resolution spectra in the 1460 - 1500 bandwidth of DARM to look at the second harmonic violin mode region, all of these might not be violin modes. I found 5 over 10^-16, 1468.4961 1472.7793, 1481.9717 (monitor filter on ETMY mode19), 1492.0198, and 1497.1934 (the worst offenders), these were reduced to 3 when I took another spectra with a smaller bw an hour later. There were also several above 10^-17, 1464.5293, 1464.0234, 1467.3916 1468.5879, 1471.2969, 1471.70121472.9668, 1482.0117, 1494.3535, 1494.3711, 1499.5937, 1500.4248. The frequencies I saw don't match the old ones reported in the wiki's violin mode table or in T1800327 but I believe these documents were from pre-O3.

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