This entry is to document a wandering line that is sometimes present between ~600hz to ~670hz in H1. This line is annoying for some burst searches (I know it shows up in the GRB-triggered X-pipeline search, and I understand it may show up in other burst searches as well). For two-detector searches, triggers caused by this line are generally caught by coherence vetos. Also, the folks running the pipeline are able to manually cut triggers from these frequencies in post-processing. So, while this is not extremely urgent, my hope is that someone will see this and have an idea of how to easily get rid of this line.
The easiest place to see this line is in the FScan plots on the detchar summary page. For example, the following is an FScan spectogram from Nov 10, you can see this line trending from 670 Hz down to 655 Hz over the course of ~14 hours (the x-axes on these plots are quite annoying): https://ldas-jobs.ligo-wa.caltech.edu/~pulsar/fscan/H1_DUAL_ARM/H1_DUAL_ARM_HANN/H1_DUAL_ARM_HANN/fscans_2015_11_10_06_00_01_PST_Tue/H1_GDS-CALIB_STRAIN/spec_620.00_720.00_H1_1131112818_1131199218.png
The 2nd harmonic shows up as well: https://ldas-jobs.ligo-wa.caltech.edu/~pulsar/fscan/H1_DUAL_ARM/H1_DUAL_ARM_HANN/H1_DUAL_ARM_HANN/fscans_2015_11_10_06_00_01_PST_Tue/H1_GDS-CALIB_STRAIN/spec_1320.00_1420.00_H1_1131112818_1131199218.png
Usually it varies more erratically: https://ldas-jobs.ligo-wa.caltech.edu/~pulsar/fscan/H1_DUAL_ARM/H1_DUAL_ARM_HANN/H1_DUAL_ARM_HANN/fscans_2015_11_08_06_00_01_PST_Sun/H1_GDS-CALIB_STRAIN/spec_620.00_720.00_H1_1130940019_1131026418.png
Sometimes, it goes away entirely: https://ldas-jobs.ligo-wa.caltech.edu/~pulsar/fscan/H1_DUAL_ARM/H1_DUAL_ARM_HANN/H1_DUAL_ARM_HANN/fscans_2015_11_16_06_00_02_PST_Mon/H1_GDS-CALIB_STRAIN/spec_620.00_720.00_H1_1131631219_1131717619.png
This line shows up in the other ifo degrees of freedom (perhaps unsurprisingly):
I had an idea to check some PSL vibration and PWR channels. There was a moment when I thought the PSL microphone was seeing the line (compare these times: STRAIN vs MIC), but I think it was a coincidence as the line in MIC stays constant even as the wandering line wanders. Nothing in the following channels:
