Reports until 10:31, Friday 31 March 2017
H1 SEI
hugh.radkins@LIGO.ORG - posted 10:31, Friday 31 March 2017 (35246)
More Insulation added to BRSY Seismo Table--Does it help? I think so.

Added more insulation to the BRSY auxcillary table supporting the T240 seismometer, see 35147, on Tuesday.  We saw improvement in the low frequency noise after insulating the supporting legs of the table, see 34869, so more on the table was warranted.

Attached are spectra before and after.

It is a little hard to see but I think the story is good.  The upper plot shows the Y axis and the X axis traces are below.  The reference traces are from 26 March 1000utc when the wind was very low.  The current traces are from 31 March 1120utc, two days after the insulation was added to the table.  Generally, comparing suggests the insulation has improved things below 60mHz.  Maybe little improvement on Y below 10mHz.

Images attached to this report