Diff for "Reference_Cavity"

Differences between revisions 6 and 8 (spanning 2 versions)

The reference cavity was locked using a 21.5 MHz signal from a rack mounted board (FSS REF - Crystal Frequency Reference http://www.ligo.caltech.edu/docs/D/D980353-C.pdf). That turned out to have many problems and we removed it completely from the system circa 2008 with a fixed 21.5 MHz OCXO from Wenzel and an RF Amplifier (see [http://nodus.ligo.caltech.edu:8080/40m/986 elog]).

We got the design parameters for the reference cavity from [http://www.ligo.caltech.edu/docs/D/D980670-00.pdf D980670]

Spacer Material	Fused Silica (Corning?)
Mirror Material	Fused Silica
Mirror T_HR	300 +/- 30 ppm
Mirror R_AR	< 500 ppm
Mirror RoC	500 mm
Cavity Length	8" (203.2 mm)
Cavity Finesse
Cavity g-factor
Cavity FSR	737.7 MHz
Cavity pole

Some FEA of the LIGO/40m reference cavity using COMSOL: /FEA

See also Frequency Stabilization Servo.

-  ⇤ ← Revision 6 as of 2009-09-12 10:32:05 → 
  Size: 883
  Editor: RanaAdhikari
  Comment:
+   ← Revision 8 as of 2009-09-12 10:36:25 → ⇥
  Size: 939
  Editor: RanaAdhikari
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
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-The reference cavity was locked using a 21.5 MHz signal from a rack mounted board (FSS REF - Crystal Frequency Reference [http://www.ligo.caltech.edu/docs/D/D980353-C.pdf]). That turned out to have many problems and we removed it completely from the system circa 2008 with a fixed 21.5 MHz OCXO from Wenzel and an RF Amplifier (see [http://nodus.ligo.caltech.edu:8080/40m/986 elog]).
+The reference cavity was locked using a 21.5 MHz signal from a rack mounted board (FSS REF - Crystal Frequency Reference http://www.ligo.caltech.edu/docs/D/D980353-C.pdf). That turned out to have many problems and we removed it completely from the system circa 2008 with a fixed 21.5 MHz OCXO from Wenzel and an RF Amplifier (see [http://nodus.ligo.caltech.edu:8080/40m/986 elog]).
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-Line 6:
+Line 7:
-|| Mirror T || 300 ppm ||
|| Mirror RoC || 1 m? ||
|| Cavity Length || 0.245 m ? ||
+|| Mirror T_HR || 300 +/- 30 ppm ||
|| Mirror R_AR || < 500 ppm ||
|| Mirror RoC || 500 mm ||
|| Cavity Length || 8" (203.2 mm) ||
-Line 11:
+Line 13:
-|| Cavity FSR || ||
+|| Cavity FSR || 737.7 MHz ||
-Line 15:
+Line 17:
-Some FEA of the LIGO/40m reference cavity using COMSOL:
[[/FEA]]
+Some FEA of the LIGO/40m reference cavity using COMSOL: [[/FEA]]
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-See also [[Frequency Stabilization Servo]].
+ See also [[Frequency Stabilization Servo]].