The objective of today's campaing is investigating the 123 Hz bump . We performed the following actions:

• Figure 1. repeated broadband acoustic injections in the sme configuration. This time the peaks excited in hrec are evident and similar to what observed in the past. Confirming that the broadband excitation observe in https://logbook.virgo-gw.eu/virgo/?r=65839 was most likely do to the effect of high microseism. A small structure at 123Hz is likely present
• Tappings in several locations (60 s each). Details are in the attached log file. A summay is the following:
  • SW NE and NW metallic structure around holding point - we find similar results as in the past
  • SWEB flange facing WE mirror - excited 165 Hz peak in hrec - Figure 4
  • link pipe - no effect in hrec
  • SWEB chamber - no effect in hrec
  • Viewport on AR side - bump at 90 Hz in hrec, 230Hz peak in B8: similar frequencies are excited in WE accelerometers; Figure 2
  • WE tower belly, excited at  90 and 167 Hz in Hrec and B8, Figure 3
• Sound beating:
  • we tested a few frequencies around 120 Hz (123, 123.5, 120, 133...). We observed in all cases a corresponding modulated excitation in Hrec. Data are to be analyzed to find correlation with modulation in accelerometers.