Документ взят из кэша поисковой машины. Адрес оригинального документа : http://zebu.uoregon.edu/~uochep/talks/talks08/G080214-00.pdf Дата изменения: Wed Jan 21 23:02:15 2009 Дата индексирования: Tue Oct 2 11:29:08 2012 Кодировка: Поисковые слова: annular solar eclipse

S5 Upconversion DQ Flags

Masahiro Ito U of Oregon L-V Meeting March 19, 2008

1


Upconversion flags
·
Upconversion flags by coil current (0.1-40Hz)

· -

Flag the times that low frequency seismic signals disturb the IFO sensitivity H1:SUS-ETMY_COIL_LL Flags for S5 2nd year done Re-run with updated scaling function in progress

Compressor noise at optics roll mode frequency (~18Hz) H2:DARM_ERR, H0:LVEA_SEISZ Compressor motor noise at LHO staging building in progress

2


Flag by coil current

· · · · ·

Use H1:SUS-ETMY_COIL_LL for coil current Find conversion factor from selected coil peaks to H1:DARM_ERR signal Make a fit curve to the conversion factors -> Scaling function, w(f) Calculate band limited RMS data with the scaling function

Make a threshold for the scaled BLRMS

3


Peaks in the H1:SUS-ETMY_COIL_LL spectrum

4


Finding how coil current at different frequencies affects H1:DARM_ERR
11/9/06 - 11/19/06 Slope of the fit line becomes conversion factor from coil to H1:DARM_ERR at this frequency

5


A fit to slopes for the different frequencies gives a scaling function of ~f^0.5 in current amplitude (~f in RMS^2)
X Slopes for test segments

6


Most of the flags in the high micro-seismic peak period
74.3% of flags in Dec. 2006

RMS

2

RMS

2

RMS

2

7


Less flags in low micro-seismic peak period
0.314% of flags in Jul. 2007

RMS

2

RMS

2

RMS

2

8


Updating scaling function

· ·

The scaling function for the first run of S5 didn't include the second mechanism of the upconversion (>10Hz) -> Require an updated scaling function Use data for entire S5 to generate the updated function

9


Updated scaling function

Second structure of upconversion included

10


To do
· ·
Estimate the noise in terms of strain or displacement Make flags for entire S5 with revised scaling function

· ·

Threshold by strain/displacement amplitude Threshold based on running statistics Multiple thresholds Include ITM damping currents

Study overlap with other flags Make flags for LLO

11


......

12


Flag for compressor noise (in progress)

· · · · ·

A source of upconversion noise Compressor motor at the LHO staging building ~30 minutes period repeats several cycles The seismic noise at optics roll mode frequecy 17~18Hz Appeared in H2:DARM_ERR at ~17.27Hz, ~34.54Hz (2nd harmonic)

13


Compressor noise frequency drift down with ~30-min. period

elog: 4/21/2007 by R.Schofield
14


Two roll mode peaks in the GW channel at 17-18Hz
17.6Hz 17.27Hz
H2 Strain Sensitivity

Strain/Sqrt(Hz)

Frequency (Hz)
15


DARM_ERR gets peaks when seismic signal at roll mode frequency

17.6Hz roll mode

17.27Hz roll mode
16


Summary

· · · ·

Coil upconversion flags for S5 2nd year is available as "COIL_UPCONVERSION" Generation of the coil upconversion flags with updated scaling function for entire S5 is in progress Upconversion flags with thresholds other than 1% dead time are planned Compressor noise flag for H2 is under investigation for channels and bands that efficiently flag the event

17