Differences between revisions 1 and 3 (spanning 2 versions)

Length Sensing and Control Design

This page discuss the design of the LSC system of the 40m Upgrade

Ports

The Power Spectrum for each port is provided. From that we identify the optimum sensing signals.

Sensing Matrix

For locking, the baseline plan is to use the same error signals of AdvLIGO:

DOF	Signal
CARM	REFL_I1
DARM	AS_DC
PRCL	POP_I1
MICH	POP_Q2
SRCL	POP_I2

In case that 3f signals will be used for lock acquisition, as a result of Optickle simulations, we propose the following sensing matrix:

DOF	Signal
X	POX
Y	POY
PRCL	REFL_32I
MICH	REFL_31I
SRCL	REFL_32Q

[...]

Cavity Absolute Lengths

Arm Cavities

Antiresonance conditions fro both sidebands [...]

=== Schnupp Asymmetry == Arguments on the Schunpp asymmetry design;

dependence on the asymmetry of central cavity's coupling
dependence of sideband output power ("throughput power" - K. Arai) to asymmetry
different designs for different PRMs (initial, temporary 10%; final 5.5%)
guidelines to change the asymmetry in different circumstances (alignment, etc.)
[...]

Power Recycling Cavity

ideal lengths
lengths corrections

Signal Recycling Cavity

ideal lengths
lengths corrections

Upgrade_09/Length_Sensing_and_Control_Design (last edited 2012-01-03 23:02:39 by localhost)

-  ⇤ ← Revision 1 as of 2010-08-02 21:46:53 → 
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  Editor: AlbertoStochino
  Comment:
+   ← Revision 3 as of 2010-08-02 22:04:12 → ⇥
  Size: 1434
  Editor: AlbertoStochino
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
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+This page discuss the design of the LSC system of the 40m Upgrade
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+The Power Spectrum for each port is provided. From that we identify the optimum sensing signals.
-----
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+For locking, the baseline plan is to use the same error signals of AdvLIGO:

|| '''DOF''' || '''Signal''' ||
|| CARM || REFL_I1 ||
|| DARM || AS_DC ||
|| PRCL || POP_I1 ||
|| MICH || POP_Q2 ||
|| SRCL || POP_I2 ||

In case that '''3f signals''' will be used for lock acquisition, as a result of Optickle simulations, we propose the following sensing matrix:

|| '''DOF''' || '''Signal''' ||
|| X || POX ||
|| Y || POY ||
|| PRCL || REFL_32I ||
|| MICH || REFL_31I ||
|| SRCL || REFL_32Q ||

[...]
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+----
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+Antiresonance conditions fro both sidebands [...]
----
=== Schnupp Asymmetry ==
Arguments on the Schunpp asymmetry design;
 * dependence on the asymmetry of central cavity's coupling
 * dependence of sideband output power ("throughput power" - K. Arai) to asymmetry
 * different designs for different PRMs (initial, temporary 10%; final 5.5%)
 * guidelines to change the asymmetry in different circumstances (alignment, etc.) 
 * [...]
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+Line 41:
+ * ideal lengths
 * lengths corrections
----
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+Line 45:
+ * ideal lengths
 * lengths corrections