Reports until 09:54, Friday 06 March 2015
H1 ISC
eleanor.king@LIGO.ORG - posted 09:54, Friday 06 March 2015 (17106)
A more stable SRMI configuration...

Kiwamu, Daniel, Elli

Yesterday we made some changes to SRMI locking and were able to stay locked much more reliablly. In this configuration I was able to take multiple measurements of SRC length without worrying about keeping lock (I'll have more to say on these results shortly..).  Lock stretches lasted for ~1hr provided noone was walking around the LVEA.  SRMI would regain lock by itself when left in the following configuration:

IMC input power 5W.  ASC master gain 0.  H1:SUS-SRM_M2_LOCK_OUTSW_L set to OFF.  H1:SUS-BS_M3_ISCINF_L_LIMIT set to 50000.

MICH input ASAIR_A_LF intrix value 0.25, MICH gain 800, MICH offset -200, MICH fliters FM7 (150^3:1), FM9(ELP40) always on and FM2 (1:0) triggered, MICH signal going to BS with outrix value 1.

SRCL input REFLAIR_A_RF9_I intrix value -3.75, SRCL gain -40000, SRCL offset 0, SRCL filters FM9(cntrl) and FM10(CLP300) always on and FM2(1:0)and FM3(4:0) triggered, SRCL signal going to SRM with outrix value 1.

(Set all other LSC matrix elements to zero.  Set power scale to 5W.  Turn on H1:LSC-CONTROL_ENABLE.)

MICH triggers on ASAIR_A_DC matrix valuen 1, upper threshold 1000, lower threshold 400.  MICH FM2(1:0) filter triggers after 0.4 sec upper threshold 1000 lower threshold 400.

SRCLtriggers on ASAIR_A_DC matrix valuen 1, upper threshold 800, lower threshold 300.  MICH FM2(1:0) filter triggers after 0.2 sec upper threshold 300 lower threshold 300.