Study of the thermal noise caused by inhomogeneously distributed loss

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

15

Scientific paper

The normal modal expansion is the most frequently used method to estimate the thermal noise of interferometric gravitational wave detectors. However, the method does not agree with new estimation methods, direct approaches, when the loss is distributed inhomogeneously. We have checked the modal expansion and direct approaches experimentally using a mechanical oscillator, such as a mirror. The experiments showed that the modal expansion is invalid. On the other hand, the measured spectra are consistent with the direct approaches. We calculated the thermal noise of a real mirror with inhomogeneous loss using the direct approaches. This calculation showed that the thermal motions caused by loss in the reflective coating and at coil-magnet actuators are comparable with the sensitivity goals of future gravitational wave detector projects. In addition, according to our calculation, a mechanical loss may cause much larger or much smaller thermal motion than is expected in modal expansion, depending on the loss distribution. The thermal fluctuation caused by coating loss is about three times larger than the estimation of the modal expansion. The thermal motion of the coil-magnet actuators is 15 times smaller. This implies that, in order to discuss the research strategy for the thermal noise, in addition to the loss quantity represented by Q-values, one should identify the distribution of all the major loss origins and use direct approaches instead of depending on the conventional modal expansion method.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Study of the thermal noise caused by inhomogeneously distributed loss does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Study of the thermal noise caused by inhomogeneously distributed loss, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Study of the thermal noise caused by inhomogeneously distributed loss will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-840692

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.