Detector Characterisation (Glitches)travasso, swinkels, fiori - 19:10 Tuesday 25 July 2017 (38830)
Print this reportComment to Some low frequency glitches last night were SDB2 scattered light arches (38815)Triggered by Excavator data (https://scientists.virgo-gw.eu/DataAnalysis/Excavator/logbook/2017-07-25_useism/) we searched for a correlation between Hrec_hoft channel vs NI_MIR_Z_50Hz channel (plot 1) and Hrec_hoft vs SDB2_LC_Z_err_ground_corrected_50Hz channel (plot 2) using a matlab-code produced by Bas: the two results are complementary. As noted by Paolo, the NI local control sensor does not see a movement of the mirror, but a movement of the ground: the scattered light path is not yet understood.
In order to match better the spectrogram, we multiplied NI_MIR channel for a factor 2 and SDB2 for a factor 1.5