aLIGO LHO Logbook

H1 SUS

Link

arnaud.pele@LIGO.ORG - posted 17:55, Wednesday 17 June 2015 - last comment - 11:20, Wednesday 24 June 2015(19208)

TFs started on ETMY and TMSY at 00:45 UTC

[sus crew]

Following the in chamber work from today at end-Y we took quick TFs on the quad and the transmon. They look ok.

Since the pump won't happen before tomorrow I started matlab tfs for all DOF.

The measurement will be running for few hours.

Images attached to this report

Comments related to this report

arnaud.pele@LIGO.ORG - 11:20, Wednesday 24 June 2015 (19306)

Link

More clue on the TMSX measurement showing a different TF than before the vent (cf log below 19246). I looked at the response from pitch and vertical drive to the individual osems (LF, RT) ~~and it looks like something is funny with the RT osem which should have the same response as the LF one, cf light red curves below~~

EDIT : Actually, LF and RT osem response are superposed on the graphs (green LF lies under red RT), so their response is the same.

Mountain View

Images attached to this comment

arnaud.pele@LIGO.ORG - 23:16, Friday 19 June 2015 (19246)

Link

EY measurements

ETMY ant TMSY transfer functions were measured on thursday after the doors went on, with chamber at atmospheric pressure. They did not show signs of rubbing, cf the first two pdf attached showing good agreement with previous measurements.

Today, I remeasured the vertical dof, after the suspension sagged ~120um from the pressure drop, and it still looks fine, cf figures below.

EX measurements

ETMX and TMSX were measured today when pressure in chamber was about 3 Torrs, after the QUAD sagged by about 130um.

ETMX TFs are similar to previous ones (3rd pdf), but the dynamics of TMSX table in pitch and vertical changed since the last measurement, cf figure below or 4th pdf. This might be ok, but the damping should be revised.