|
⇤ ← Revision 1 as of 2019-11-30 20:43:51
Size: 1194
Comment:
|
Size: 1258
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 8: | Line 8: |
| * Identifies the exact position of the resonance peaks in amplitude spectral densities, * Reads the cross-coupling ratios from transfer functions at the resonant frequencies and |
* Identifies the exact position of resonant peaks in measured amplitude spectral densities, * Reads cross-coupling ratios from transfer functions at the resonant frequencies and |
| Line 12: | Line 12: |
| * Note that in other klog entries these ratios are written without the appropriate units and multiplied by a factor of 100 with a percetage sign. '''This practice should be avoided.''' | * Note that in other klog entries these ratios are written without the appropriate units. They are simply multiplied by a factor of 100 and are claimed to be a percentage. '''This practice is misleading and should be avoided.''' |
| Line 17: | Line 17: |
| * Any imbalance in the driving coils does not depend on the frequency of the actuation. | * The diagonalization Any imbalance in the driving coils does not depend on the frequency of the actuation. |
Describe KAGRA/Subgroups/VIS/OpsManual/OpLev/TypeA here.
In construction
Introduction
This diagonalization procedure is based on klog entry 10786., which is in turn based on the scheme described in entry 10729.
- The procedure relies on a script written by Lucia and Terrence which
- Identifies the exact position of resonant peaks in measured amplitude spectral densities,
- Reads cross-coupling ratios from transfer functions at the resonant frequencies and
- Calculates the new diagonalization matrix.
The final results are given as coupling ratios with appropriate units in terms of µrad and µm. For example, the ratio for L to P coupling is in units of µrad/µm.
Note that in other klog entries these ratios are written without the appropriate units. They are simply multiplied by a factor of 100 and are claimed to be a percentage. This practice is misleading and should be avoided.
The physics underlying the procedure is the following:
- At the resonant frequencies the
- The diagonalization Any imbalance in the driving coils does not depend on the frequency of the actuation.