=========================================================================== Note 1: Input matrix changes. -- possibly significant, affects calibration. L1:LSC-ITMTRX_01 0.013000 0.012000 L1:LSC-ITMTRX_12 0.200000 0.180000 L1:LSC-ITMTRX_23 -0.650000 -0.670000 L1:LSC-ITMTRX_34 0.055000 0.051000 L1:LSC-PRC_GAIN -0.125297 -0.100237 ITMTRX: input matrix for the LSC controls; this is the only time they were changed during S2. Rana and Gary were setting up the ifo; the input matrix in seg2 are the "good" ones. Same is true for PRC gain. (Note: the down script set the ASQ matix element to 0.011, the up script to 0.012, so there are many changes of this setting during S2, but not in science segments). 01: AS_Q -> DARM_ERR 12: PO_I -> PRC_ERR 23: PO_Q -> MICH_ERR 34: REFL_I -> CARM_ERR ========================================================================== Note 2: PRC filter changes. Possibly significant. L1:LSC-PRC_SW1R_bit14 This is the 60 Hz comb filter, FM6. This filter was turned ON in "up" scripts saved on Feb 14, Feb 28 and Mar 11, by setting the bit 13, and I presume the filter was turned on by all the up scripts during S2. This is consistent with bit 13 (filter request) being ON for all science segments; however bit14 is ON most of science segments, but not all (seethe ones below). I think this probably means the filter was not on, but I have to investigate more. 729336255- 729342311 2003 02/15 09:24:02 - 02/15 11:04:58 utc **varies** 729363873- 729364061 2003 02/15 17:04:20 - 02/15 17:07:28 utc **varies** 729386465- 729386604 2003 02/15 23:20:52 - 02/15 23:23:11 utc Off 729422903- 729427038 2003 02/16 09:28:10 - 02/16 10:37:05 utc Off 729499828- 729500062 2003 02/17 06:50:15 - 02/17 06:54:09 utc Off 729506937- 729510004 2003 02/17 08:48:44 - 02/17 09:39:51 utc Off 729512593- 729512688 2003 02/17 10:23:00 - 02/17 10:24:35 utc Off 729519088- 729521630 2003 02/17 12:11:15 - 02/17 12:53:37 utc Off 729526253- 729526409 2003 02/17 14:10:40 - 02/17 14:13:16 utc Off 729527140- 729527301 2003 02/17 14:25:27 - 02/17 14:28:08 utc Off 729527956- 729528416 2003 02/17 14:39:03 - 02/17 14:46:43 utc Off On Feb 16 elog, I was on shift, and made a note about these filters, see Note 3 below. ============================================================================= Note 3: Michelson filters: possibly significant. L1:LSC-MICH_SW1R_bit*: Two filters, FM3 1.2 Hz resonant gain (bits 8 and 9) and FM6 60Hz comb (bits 12 and 13) had different states during S2. Differently than for the PRC FM6, both bits (request and readback) were consistent with each other, so they represent the actual state of the filter. In the up script saved on Feb 14, there are two lines turning on FM6 and FM8 commented out; however they probably referred to filters that had been erased to make LSC headroom for S2 (FM8 is an empty bank now). In the Feb 28 script there is a request to the operator to turn on FM5 (18 Hz notch filter). After Feb 28, changes to the up script were logged (thanks to Szabi AVH), and there are no changes pertaining MICH filters. So, I assume these filters were turned on by hand, by operators; there is a note in the ilog (made by myself!) on Feb 16, talking about Seg18, starting at 729422904, suggesting we did indeed turn these filter on by hand: "(In this lock stretch, we forgot to engage FM3-MICH and FM6-PRC, but obviously we had a good spectrum. Maybe we should study whether these filters increase the noise, although it is unlikely). " FM3 (bit 9, 1.2 Hz resonant gain) was usually ON, except on a few segments on Feb 15-17: 729350749- 729350905 2003 02/15 13:25:36 - 02/15 13:28:12 utc Off 729422903- 729427038 2003 02/16 09:28:10 - 02/16 10:37:05 utc Off 729457609- 729457971 2003 02/16 19:06:36 - 02/16 19:12:38 utc Off 729499828- 729500062 2003 02/17 06:50:15 - 02/17 06:54:09 utc Off 729526253- 729526409 2003 02/17 14:10:40 - 02/17 14:13:16 utc Off 729527140- 729527301 2003 02/17 14:25:27 - 02/17 14:28:08 utc Off FM6 (bit 13, 60 Hz comb) was usually OFF, except in the segments below. These were all in 10 days: Feb 28, Mar 1-5, Mar 14, 16, 22 and 25. 730458454- 730472962 2003 02/28 09:07:21 - 02/28 13:09:09 utc On 730495197- 730498869 2003 02/28 19:19:44 - 02/28 20:20:56 utc On 730503121- 730503598 2003 02/28 21:31:48 - 02/28 21:39:45 utc On 730541138- 730548340 2003 03/01 08:05:25 - 03/01 10:05:27 utc On 730566539- 730571749 2003 03/01 15:08:46 - 03/01 16:35:36 utc On 730574789- 730578669 2003 03/01 17:26:16 - 03/01 18:30:56 utc On 730580155- 730584460 2003 03/01 18:55:42 - 03/01 20:07:27 utc On 730587029- 730602341 2003 03/01 20:50:16 - 03/02 01:05:28 utc On 730603408- 730609518 2003 03/02 01:23:15 - 03/02 03:05:05 utc On 730610536- 730631793 2003 03/02 03:22:03 - 03/02 09:16:20 utc On 730644254- 730654453 2003 03/02 12:44:01 - 03/02 15:34:00 utc On 730656264- 730656569 2003 03/02 16:04:11 - 03/02 16:09:16 utc On 730665045- 730669961 2003 03/02 18:30:32 - 03/02 19:52:28 utc On 730671506- 730672705 2003 03/02 20:18:13 - 03/02 20:38:12 utc On 730677950- 730695910 2003 03/02 22:05:37 - 03/03 03:04:57 utc On 730696303- 730697742 2003 03/03 03:11:30 - 03/03 03:35:29 utc On 730699764- 730721149 2003 03/03 04:09:11 - 03/03 10:05:36 utc On 730722548- 730726499 2003 03/03 10:28:55 - 03/03 11:34:46 utc On 730727350- 730727656 2003 03/03 11:48:57 - 03/03 11:54:03 utc On 730788720- 730805156 2003 03/04 04:51:47 - 03/04 09:25:43 utc On 730809119- 730811968 2003 03/04 10:31:46 - 03/04 11:19:15 utc On 730813296- 730813761 2003 03/04 11:41:23 - 03/04 11:49:08 utc On 730872167- 730879401 2003 03/05 04:02:34 - 03/05 06:03:08 utc On 730880598- 730886849 2003 03/05 06:23:05 - 03/05 08:07:16 utc On 730903124- 730904048 2003 03/05 12:38:31 - 03/05 12:53:55 utc On 731658153- 731659014 2003 03/14 06:22:20 - 03/14 06:36:41 utc On 731675064- 731679593 2003 03/14 11:04:11 - 03/14 12:19:40 utc On 731822687- 731830317 2003 03/16 04:04:34 - 03/16 06:11:44 utc On 731832522- 731834994 2003 03/16 06:48:29 - 03/16 07:29:41 utc On 732369885- 732370088 2003 03/22 12:04:32 - 03/22 12:07:55 utc On 732600550- 732605500 2003 03/25 04:08:57 - 03/25 05:31:27 utc On ============================================================================ Note 4: Wavefront Sensor -- possibly significant. WFS1 Feb 16, 5am, seg19: only segment with these filters, FM8, turned on (I think they are integrators). Again, I was on shift. L1:ASC-WFS1_PIT_SW2R 1840.000000 1852.000000 L1:ASC-WFS1_PIT_SW2R_bit2 Off On L1:ASC-WFS1_PIT_SW2R_bit3 Off On L1:ASC-WFS1_YAW_SW2R 1840.000000 1852.000000 L1:ASC-WFS1_YAW_SW2R_bit2 Off On L1:ASC-WFS1_YAW_SW2R_bit3 Off On ============================================================================= Note 5: Tidal servo offsets -- not significant We (Mike F. Gaby G) were introducing offsets trying to make the lock stretches last longer. No influence on the data quality. L1:TID-DMXARM_OFFSET 0.000000 -55.000000 L1:TID-DMXARM_OFFSET_ENABLE Disable Enable L1:TID-DMYARM_OFFSET 0.000000 -55.000000 L1:TID-DMYARM_OFFSET_ENABLE Disable Enable L1:TID-DMXARM_OFFSET -55.000000 0.000000 L1:TID-DMXARM_OFFSET_ENABLE Enable Disable L1:TID-DMYARM_OFFSET -55.000000 0.000000 L1:TID-DMYARM_OFFSET_ENABLE Enable Disable ============================================================================ Note 6: Offsets. --unlikely to be significant They change whenever the RF environment changes in the LVEA (i.e., opening rack doors, andmore significantly, power outages, etc). The change in itself does not have an influence in data quality; however if they are taken as indications that the previous segments had a significant non-zero offset, that may have an effect in data quality. We can probably get the offsets by measuring signals when the interferometer is out of lock, but this would require a fair amount of work. No special notes about why offsets weret uned at this particula time. L1:LSC-AS1_I_OFFSET -1369.020546 -1356.253033 L1:LSC-AS1_Q_OFFSET 612.839920 613.809763 L1:LSC-POB_I_OFFSET -189.628686 -189.962527 L1:LSC-POB_Q_OFFSET 22.971241 23.140129 L1:LSC-REFL_I_OFFSET 27.064834 27.232396 L1:LSC-REFL_Q_OFFSET -137.355378 -138.455069 L1:ASC-WFS1_D2Ofs 0.032408 0.031973 L1:ASC-WFS1_D3Ofs 0.029695 0.030574 L1:ASC-WFS1_D4Ofs 0.037160 0.037661 L1:ASC-WFS1_I1_OFFSET -172.007318 -173.141904 L1:ASC-WFS1_I2_OFFSET -112.032165 -113.518218 L1:ASC-WFS1_I3_OFFSET -81.608498 -83.053175 L1:ASC-WFS1_I4_OFFSET -147.088164 -147.129101 L1:ASC-WFS1_Q1_OFFSET -138.162263 -138.752011 L1:ASC-WFS1_Q2_OFFSET 100.490745 101.058400 L1:ASC-WFS1_Q3_OFFSET -67.652654 -67.963382 L1:ASC-WFS1_Q4_OFFSET -134.538602 -135.478193 =========================================================================== Note 7: Status settings. -- not significant Changes in "...NOM" or "..TOL" or "... MASK" values only indicate settings for the status screeen, no influence in data quality (unless we want to second guess the reason for changing the nominal settings). L1:LSC-LA_PTRT_OFFSETNOM -33.300000 -32.000000 L1:LSC-LA_PTRT_SLOPENOM 22.500000 20.000000 L1:LSC-ISCT4EO_HIHV_ADJTOL 0.010000 0.300000 L1:ASC-QPDX_PIT_GAINNOM 1.000000 0.000000 L1:ASC-QPDX_YAW_GAINNOM 1.000000 0.000000 L1:LSC-ASI_CORR_SW1MASK 0.000000 4095.000000 L1:LSC-ASI_CORR_SW1NOM 49348.000000 62404.000000 L1:LSC-ASI_CORR_SW2MASK 0.000000 4095.000000 L1:LSC-ASI_CORR_SW2NOM 2032.000000 960.000000 ======================================================================== Note 8: QPDX settings -- probably not significant These changes were made (Rana, Gaby) under the suspicion that we had spurious signals in the QPDs (where PIT and YAW are not used for any loop yet). This gain did not kill the noisy PIT/YAW output we were seeing, but these signals do not go anywhere anyway. L1:ASC-QPDX_PIT_GAIN 1.000000 0.000000 L1:ASC-QPDX_YAW_GAIN 1.000000 0.000000 ================================================================== Note 9: Lock acquisition parameters - not significant Offset and slope for PTRR, PTRT change the efficiency of the lock acquisition, but does not do anything to detection mode. The nominal values are also only used for the status screen, also not significant. L1:LSC-LA_PTRT_OFFSET -32.550000 -31.900000 L1:LSC-LA_PTRT_SLOPE 22.500000 19.500000 ==================================================================== Note 10: EO shutter HiHV level/ASQ input gain --significant the last part of the "up" script turns up the power on the AS PD y opening the EO shutter, and reducing the ASQ input gain. If it is opened too much, there may be saturation due to high DC power or high RF on the PD. We observed the interferometer losing lock if the ASDc power flucutations exceeded a not so-well defined threshold. On the other hand, the more power, the less shot noise (or, rather, the better signal-to-noise ratio). We used different levels trying to reach a compromise that allowed. The power level will definitely change the dta quality, although in ways that are not obvious, since the actual power on the PD depends not only on the EO shutter level, but on the alignment. The changes in EO shitter and ASQ gain should come in pairs, but they don't always (although that is not necessarily bad). L1:LSC-ISCT4EO_HIHV_ADJ 1.194000 1.114000 L1:LSC-AS1_Q_GAIN 0.005599 0.004263 ============================================================================= Note 11: LVEA PEPI changes -- possibly significant L1:BSC1-PEPI_ENABLE Disable Enable L1:BSC3-PEPI_ENABLE Disable Enable L1:BSC1-PEPI_ENABLE Enable Disable L1:BSC3-PEPI_ENABLE Enable Disable Normally, LVEA PEPI system (active seismic isolation for ITMs) is off, because of suspicions that it increases Michelson noise by increasing the relative motion of ITMs with respect to BS, RM. We usually lock with LVEA PEPI on to help the arms, then turn them off with the up script. Joe Giaime was on shoft this day, it is likely he tried to see hwether there was any actual difference to confirm suspicions. However, there is no explicit mention of this in the ilog. Segments 89-92, 133, 139, 141 had LVEA PEPI enabled. ============================================================================= Note 12: SEI MS FF tuning -- possibly significant On Feb 22 ilog, Joe Giaime's entry on "Parameter tweaking of microseism feedforward" explains slight changes to the microseismic feedforward system. The new settings, used for Segs 94 onwards, should have slightly imprved gain at 0.3 Hz. L1:SEI-CM_EXX_SW1R 53236.000000 4084.000000 L1:SEI-CM_EXX_SW1R_bit14 On Off L1:SEI-CM_EYY_SW2R 1539.000000 1536.000000 L1:SEI-CM_EYY_SW2R_bit1 On Off L1:SEI-CM_LVEAX_SW1R 53236.000000 4084.000000 L1:SEI-CM_LVEAX_SW1R_bit14 On Off L1:SEI-CM_LVEAX_SW1R_bit15 On Off L1:SEI-CM_LVEAY_SW2R 1539.000000 1536.000000 L1:SEI-CM_LVEAY_SW2R_bit1 On Off L1:SEI-DF_EXX_SW1R 53236.000000 4084.000000 L1:SEI-DF_EXX_SW1R_bit14 On Off L1:SEI-DF_EYY_SW2R 1539.000000 1536.000000 L1:SEI-DF_EYY_SW2R_bit0 On Off L1:SEI-DF_EYY_SW2R_bit1 On Off L1:SEI-DF_LVEAX_SW1R 53236.000000 4084.000000 L1:SEI-DF_LVEAX_SW1R_bit14 On Off L1:SEI-DF_LVEAY_SW2R 1539.000000 1536.000000 L1:SEI-DF_LVEAY_SW2R_bit0 On Off L1:SEI-DF_LVEAY_SW2R_bit1 On Off L1:SEI-FASY_GAIN 0.470000 0.490000 ==================================================================== Note 13: ??? L1:PSL-STAT_MOPA_MIN_OUT 5.000000 4.500000 ==================================================================== Note 14: MC2 problems?? L1:SUS-MC2_SUSPOS_SW2R 1024.000000 1536.000000 L1:SUS-MC2_SUSPOS_SW2R_bit9 Off On ===================================================================== Note 15: Michelson gain -- likely significant At times, oscillations in the Michelson loop were observed, and cured with a reduction of the loop gain. There is an ill-understood, but sometimes present coupling of nois ein the Michelson signal (POBQ) and in the gw signal (ASQ), so changes in MICH gain may flag significant change sin ASQ data quality . L1:LSC-MICH_GAIN -0.080000 -0.060000 ====================================================================== Note 16: ??? L1:LSC-AIOMXARM_TMFEEDBACK.KP -0.000500 -0.000100 L1:LSC-AIOMYARM_TMFEEDBACK.KP -0.000500 -0.000100 L1:LSC-CM_MCFMON_FEEDBACK.KI 1000.000000 10.000000 L1:LSC-CM_MCFMON_FEEDBACK.KP -0.001000 -0.100000 ====================================================================== Note 17: ?? L1:TID-SIN_PER 1.000000 2.000000 ====================================================================== Note 18: ASI servo gain --likely significant The ASI servo is a feedback loop with the RF signal of the ASPD to keep the ASI signal small, and avoiding saturation. Changes in gain in this servo are liekly to be significant. This gain was changed only for segment 112. L1:LSC-ASI_CORR_GAIN 4.300000 5.000000 ===================================================================== Note 19: PRC_DAMP switches, filters This is an LSC loop which is not used, its output signal does not go anywhere, the gain was set to zero during all of S2. Thefilters were probably turned on or off by mistake in seg 133. L1:LSC-PRC_DAMP_SW2R 3840.000000 0.000000 L1:LSC-PRC_DAMP_SW2R_bit10 On Off L1:LSC-PRC_DAMP_SW2R_bit11 On Off L1:LSC-PRC_DAMP_SW2R_bit8 On Off L1:LSC-PRC_DAMP_SW2R_bit9 On Off ===================================================================== Note 20: non-changes --very likely not significant Some changes seem to record changes insignificant to numerical precision: L1:LSC-AS1_I_LIMIT -0.000000 0.000000 ===================================================================== Note 21: PSL recovery from power outage. See Rana's entries on Mar 8,9 L1:PSL-FSS_LOCKEDLEVEL 1.000000 2.000000 L1:PSL-FSS_MGAIN 7.000000 10.000000 L1:PSL-ISS_OUTERLOOPGAIN -10.000000 0.000000 L1:PSL-ISS_TESTINNER OFF ON L1:PSL-ISS_TESTOUTER OFF ON L1:PSL-PMC_INOFFSET 2.073180 2.100000 L1:PSL-PMC_LOCK ACQUIRE DISABLE L1:PSL-STAT_FSS_NOM_C_GAIN 7.000000 10.000000 L1:PSL-STAT_MOPA_MIN_OUT 4.500000 5.000000 L1:PSL-STAT_PMC_NOM_INOFFSET 2.070000 2.100000 ======================================================================= Note 22: ITMX recovery after coming back from power outage on Mar 6, ITMX was oscillating L1:SUS-ITMX_DEWHITE_SW1R 31.000000 63.000000 L1:SUS-ITMY_DEWHITE_SW1R 63.000000 31.000000 L1:SUS-ITMY_OLPIT_GAIN -200.000000 -150.000000 L1:SUS-ITMY_OLYAW_GAIN 200.000000 150.000000 ===================================================================== Note 23: MC ASC inputs L1:SUS-MC1_ASCPIT_GAIN 1.000000 0.000000 L1:SUS-MC1_ASCPIT_GAINNOM 1.000000 0.000000 L1:SUS-MC1_ASCPIT_SW2NOM 1536.000000 512.000000 L1:SUS-MC1_ASCPIT_SW2R 1536.000000 512.000000 L1:SUS-MC1_ASCPIT_SW2R_bit10 On Off L1:SUS-MC1_ASCYAW_GAIN 1.000000 0.000000 L1:SUS-MC1_ASCYAW_GAINNOM 1.000000 0.000000 L1:SUS-MC1_ASCYAW_SW1NOM 4.000000 0.000000 L1:SUS-MC1_ASCYAW_SW1R 4.000000 0.000000 L1:SUS-MC1_ASCYAW_SW1R_bit2 On Off L1:SUS-MC1_ASCYAW_SW2NOM 1536.000000 512.000000 L1:SUS-MC1_ASCYAW_SW2R 1536.000000 512.000000 L1:SUS-MC1_ASCYAW_SW2R_bit10 On Off L1:SUS-MC1_PIT_COMMTOL 0.000000 0.001000 L1:SUS-MC1_YAW_COMMTOL 0.000000 0.001000 L1:SUS-MC2_YAW_COMMTOL 0.000000 0.001000 L1:SUS-MC3_PIT_COMMTOL 0.000000 0.001000 L1:SUS-MC3_YAW_COMMTOL 0.000000 0.001000