More peak hunting for the 4.05 Hz bumps. I tweaked a bit the parameters for my peak finder code, adn the channel list got a bit bigger. Full list below.
Most interesting are
H1:PEM-CS_ACC_ISCT1_REFL_Y_DQ
H1:PEM-CS_ACC_LVEAFLOOR_HAM6_Z_DQ
H1:PEM-CS_TILT_LVEA_VERTEX_T_DQ
It looks like something it's shaking the ground at 4.05 Hz in the LVEA. The 4.,05 Hz peak in those channels is coherent.
H1:PEM-CS_ACC_ISCT1_REFL_Y_DQ
H1:PEM-CS_ACC_LVEAFLOOR_HAM6_Z_DQ
H1:PEM-CS_ADC_5_26_2K_OUT_DQ
H1:PEM-CS_ADC_5_29_2K_OUT_DQ
H1:PEM-CS_MAG_EBAY_LSCRACK_Y_DQ
H1:PEM-CS_MAG_EBAY_LSCRACK_Z_DQ
H1:PEM-CS_MAG_EBAY_SUSRACK_Y_DQ
H1:PEM-CS_MAG_EBAY_SUSRACK_Z_DQ
H1:PEM-CS_MAG_LVEA_VERTEX_X_DQ
H1:PEM-CS_MAG_LVEA_VERTEX_Z_DQ
H1:PEM-CS_RADIO_EBAY_NARROWBAND_1_DQ
H1:PEM-CS_RADIO_EBAY_NARROWBAND_2_DQ
H1:PEM-CS_RADIO_LVEA_NARROWBAND_1_DQ
H1:PEM-CS_RADIO_LVEA_NARROWBAND_2_DQ
H1:PEM-CS_TILT_LVEA_VERTEX_T_DQ
H1:PEM-EX_ADC_0_09_OUT_DQ
H1:PEM-EX_LOWFMIC_VEA_FLOOR_DQ
H1:PEM-EX_MAG_EBAY_SUSRACK_X_DQ
H1:PEM-EX_MAG_EBAY_SUSRACK_Y_DQ
H1:PEM-EX_MAG_EBAY_SUSRACK_Z_DQ
H1:PEM-EX_TEMPERATURE_BSC9_ETMX_DQ
H1:PEM-EX_VMON_ETMX_ESDPOWER48_DQ
H1:PEM-EY_ADC_0_14_OUT_DQ
H1:PEM-EY_MAG_EBAY_SEIRACK_X_DQ
H1:PEM-EY_MAG_EBAY_SEIRACK_Y_DQ
H1:PEM-EY_MAG_EBAY_SEIRACK_Z_DQ
H1:PEM-EY_MAG_EBAY_SUSRACK_X_DQ
H1:PEM-EY_MAG_EBAY_SUSRACK_Y_DQ
H1:PEM-EY_MAINSMON_EBAY_2_DQ
H1:CAL-PCALX_IRIGB_DQ
H1:CAL-PCALY_IRIGB_DQ
LVEA magnetometers are coherent with the ground motion. Is there some big electrical machine shaking the ground and making a magnetic field at the same frequency?
The 4.05 Hz line in the CS accelerometers have to be electrical coupling. They're identical in shape and amplitude ISCT1 and HAM6 despite being different DoFs and locations. They also are coherent with an unused ADC channel, PEM-CS_ADC_5_29_2K. It was used for DAQ stand testing but right now it's almost certainly disconnected. It sees a structure of odd harmonics of 1.35 Hz (4.05 is the third harmonic) which is coherent with both of the accelerometers. I think this structure is contaminating all of the electronics in the CS that Gabriele has identified. The PSDs, a zoomed PSD, and the coherence are attached. So it's not motion, but it does mean there's electrical noise at 4.05 Hz, and it's in many PEM channels at least. The current clamp ADC_5_26 sees it, but is it actual current or just in the ADC?
