(OMC) DC (DCPD) readout (Power) Normalization (Linearization)

Document #:

LIGO-T0900023-v2

Document type:

T - Technical notes

Abstract:

We describe the proposed method for converting the DC readout signal into DARM for use in Enhanced LIGO.

Files in Document:

• PDF document (T0900023-01.pdf, 101.9 kB)

Other Files:

• TeX file and figures (T0900023-01.zip, 118.4 kB)
• source code of eLIGO implementation (OMC_DCERR.c, 8.9 kB)

Topics:

• Sensing and Control
• Commissioning

Authors:

• Sam Waldman

Keywords:

eLIGO Enhanced OMC DC

Notes and Changes:

Updated file to 1) add section about parameter measurement, 2) deprecate the second normalization scheme and 3) include the crazy quadratic term.

v2 is equivalent to 01.

There seems to be a sign error in T0900023-v2 equation (3) (sign of x_0 term should be negative). However, the eLIGO implementation had the correct sign.

Referenced by:

• LIGO-E1300898: eLIGO, ISC, OMC
• LIGO-E1300893: aLIGO, ISC, OMC, Design, General