• Title: 09/15 OWL Shift: 7:00-15:00UTC (00:00-8:00PDT), all times posted in UTC
  

• State of H1: Observation Mode at 60 Mpc for the past 9 hours. The range has been dropping slowly. 
  

• Support: I called Jenne about the 2Hz comb. Thomas Abbott was helping me with the comb hunting.
  

• Shift Summary: Besides the nasty looking 2Hz comb up to 100Hz, seismic activity was minimal. Wind speed <=10mph. The 2Hz comb shows up on EY SUSRACK magnetometer, ETMY top stage F1, F2, and SD, OMC DCPD, and ETMY ISI ST2 GS13.

• Incoming Operator: Patrick

• Activity Log:

• 12:00 UTC Christina and Karen on site.

• 15:00 Handing off to Patrick

•  

There's an increase in seismic activity at 0.1-0.3 Hz band. Wind speed ~10 mph. The 2Hz comb is still present. Thomas Abbott has been helping me figuring out where it could have come from (alog21528)

Note: while investigating the 2Hz glitches we noticed 1Hz glitches at EX seirack magnetometer.

This 2 Hz comb is actually glitches every half a second. It seems like the period is not exactly half a second. They appear in DARM but not MICH, SRCL, or PRCL, so it's probably not a bad PR or SR mirror driver.

Attached are a few Omega scans. The first is several seconds long and shows that these are very short and span about 40 to 100 Hz. The next three Omega scans are 4 seconds apart, showing that these don't sit right on the integer second and have a period that is not quite 0.5 seconds.

• Title: 09/15 OWL Shift: 7:00-15:00UTC (00:00-8:00PDT), all times posted in UTC
  

• State of H1: Observation Mode at 60Mpc for the last 2.5 hrs. Was at 70 Mpc before.
  

• Outgoing Operator: Ed M.
  

• Quick Summary: The 2Hz comb appeared on DARM 2.5 hours ago for no apparent reason. It shows up on EY SUS rack magnetometer. I called Jenne and she suggested I leave it there since the ifo is still locked. The light in the LVEA is on. No one else is on site. Wind speed below 10 mph. No seismic activity.

TITLE:  Sep 14 EVE Shift 23:00-07:00UTC (16:00-00:00 PDT), all times posted in UTC

STATE Of H1: Observing

SUPPORT: Jenne Driggers was called about comb oscillation in DARM

INCOMING OPERATOR: Nutsinee

05:50 a 2Hz comb appeared in DARM from ~20Hz to ~100Hz (as far as I can tell as it gets lost in the bucket)) which resulted in a drop in range to ~63Mpc. I placed a call to Jenne who was on call to inquire as to how I should proceed and the advice was as long as were locked, stay locked. So, we're still locked and Observing at 63Mpc.

C. Cahillane

I have made a file in /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/ER8/H1/Scripts/compare_actcoeffs_ER8_craig_extrapolation.m
The purpose of this file is to find the frequency dependence of our uncertainty in A_pu and A_tst.  It takes our three measurements from August 26, 28, and 29 and finds their weighted means and weighted standard deviations at all frequencies.  (Thank you Jeff, Kiwamu, and Darkhan for the code infrastructure.)

I have used the Pcal measurements only for our uncertainty calculations since it is has the lowest uncertainty and is the main method of calibrating our actuators.  Free Swinging Mich and ALSDIFF are used to determine the accuracy of Pcal, and Pcal is relatively very precise.
Our measurements go from 3 Hz to 100 Hz, but I need uncertainty from 3 Hz to 5000 Hz, so I am currently using a Zeroth Order Extrapolation, which is basically where I take our final uncertainty value at 100 Hz and let that be our uncertainty value for all data points from 100 Hz to 5000 Hz.  
It is expected that the actuation term will fall off quickly after 100 Hz and this will be sufficient for our first-order result.  If actuation is the main contribution to uncertainty more intelligent steps must be taken to ensure we aren't underestimating our uncertainty.

I will do the same tomorrow with the sensing function residual C_r, probably using Zeroth Order Extrapolation down to low frequency in this case.

Plot 1, 2, and 3 represent our UIM, PUM, and TST actuation stages.  For now I will fold systematic error and statistical uncertainty together, i.e. if we have an |A_tst| std of 0.5 m/ct and a systematic residual of 3%, I will make our total uncertainty be 0.5^2 + ( 0.03 * |A_tst| )^2.  

Summary: IFO locked since my shift started. Aside from the earlier noise trouble we’ve been locked at ~ 72Mpc. No EQs showing and wind is calm. A couple of ETMY glitches dropped te range to 10Mpc. Rick and the Pcal team still hard at work.

00:55UTC The Transient Injection was toggled to "Disable"

TITLE: Sep 14 EVE Shift 23:00-07:00UTC (16:00-00:00 PDT), all times posted in UTC

STATE Of H1: Observing

OUTGOING OPERATOR: Jim Warner

QUICK SUMMARY:Control room is pretty full of the usual suspects. Lights are on in the LVEA. Wind is below 20mph. EQ activity is quiet. IFO is experiencing some anomalous broad band noise. Commissioners are working on a solution.

J. Kissel

Since updates to the CAL-CS model have been a little sporadic over the past few days, I recap below what happened when, as logged by the filter archive.
What Changed                                                                    Local Time (PDT)    Corresponding Archive of Change    Corresponding aLOG

SUS dynamical model update is complete                                          Thu Sep 10 13:50    H1CALCS_1125953445.txt             LHO aLOG 21322

Cavity pole frequency changed from 389 to 341 [Hz] (+optical gain name change)  Thu Sep 10 14:03    H1CALCS_1125954209.txt
Optical gain is renamed (no substantial change)                                 Thu Sep 10 14:03    H1CALCS_1125954234.txt   
DARM_ERR Optical gain is tuned                                                  Thu Sep 10 17:49    H1CALCS_1125967809.txt             LHO aLOG 21385

Installed inverse actuation filter                                              Sun Sep 13 22:35    H1CALCS_1126244167.txt             LHO aLOG 21487

Kiwamu changes L1 and L2 violin modes                                           Mon Sep 14 09:03    H1CALCS_1126281835.txt             LHO aLOG 21500

Copied new inverse actuation filter over to blind injection                     Mon Sep 14 09:08    H1CALCS_1126282148.txt             
Changed the names of the blind injection filter banks (no substantial change)   Mon Sep 14 09:09    H1CALCS_1126282176.txt             LHO aLOG 21499
(Note the filter files are tagged with the GPS time that they're created. so they're more accurate (to the second) than the local time I quote.)

Given that the DARM calibration was tuned at Sep 10 2015 17:49:00 PDT = Sep 11 2015 00:49:00 UTC, and Kiwamu started the PCAL to CAL-DELTAL_EXTERNAL transfer function at Sep 10 2015 18:08:12 PDT = Sep 11 2015 01:08:12 UTC, I would conlcude that 
the front-end calibration has been stable for LHO since the first lock stretch that was placed in observation mode after that measurement, which starts at 
     1125972087 = Sep 11 2015 02:01:10 UTC = Sep 10 2015 19:01:10 PDT
until the last observation stretch -- which ended at 
     1126281754 = Sep 14 2015 16:02:17 UTC = Sep 14 2015 09:02:17 PDT
-- before Kiwamu's change at Sep 14 2014 09:03:00 PDT = Sep 14 2015 16:03:00 UTC. 

I say the front end calibration has been "stable" instead of "valid" because because we know that Kiwamu's work this morning was to correct a systematic error from a bug that had been found.

We only briefly took the IFO out of observation mode (though the IFO stayed happily locked) while Kiwamu loaded new SUS filters and I the copy of inverse actuation filters. We resumed a new observation segment Sep 14 2015 16:10:43 UTC.

As noted in Kiwamu's most recent aLOG about updating the calibration this morning (LHO aLOG 21500), his update changed the UIM and PUM stages, and for features well-above the cross-over frequencies of those stages (TST/ PUM ~30-40 [Hz], PUM / UIM ~ 2 [Hz]). The update was a bug fix, and it means that the front is now more accurately representing the violin modes that were already correct in the DARM model. We all suspect this is a small change in the overall actuation function, but the recent discovery of how poorly the PUM has been rolled off (LHO aLOG 21419), means we have to verify. 

After these messages, we'll be riiiight back. *whistle glitch*

P.S. Since Matt and I performed all of our inverse actuation filter design on the original matlab model of the DARM actuation function, the inverse actuation filter design and implementation is unaffected by Kiwamu's change, nor was it impacted by the systematic error that he found.

Mike Landry & Vern Sandberg  ER8 to O1 Transition

Cancellation of Tuesday Maintenance Day, September 15, 2015 to allow for IFO ER8-Quality data collection.

• Title: 9/14 Day Shift: 15:00-23:00UTC all times posted in UTC

• State of H1: Observation Mode at 70Mpc for the last 8hrs

• Support: All the commissioners

• Shift Summary: Mostly quiet, but worsening range at the end 

• Activity Log:

• 15:30 Ken working at warehouse, hooking up wiring for fire suppression system
  16:00 ChrisS and JoeD working on arm, recalled at 18:20, 
  16:00 Kiwamu and JeffK working on calibration and hardware injections for a couple minutes
  16:15 Bubba and JohnW driving down Xarm to investigate an air compressor 250m from EX, done 17:20
  16:45 Hugh at EY
  16:45 Fil to CER, out at 16:55
  17:00 Hugh at EX, out at 17:10
  17:55 Hugh in Mechanical Room checking HEPI fluid levels
  ~22:20 Range starts getting ratty and DMT OMEGA scans on control room display shows we are getting glitchy, numerous ETMY saturations
   
   
   

Checked the Reservoir Levels this morning.  All steady; no further maintenance called for.

While we were in commisioing mode, we had a strange non stationary spectrum, with large non stationary noise also appearing in MICH and PRCL.  I quickly looked at some triple witness sensors, since we've had issues with these recently, but didn't see anything obvious.  

The strange noise started a few minutes before 2:50:34 UTC Sept 10, seemed to get better for a few minutes and then got worse again around 2:57:21. 

We don't think that this was related to any comissioning we were doing.  Evan had temporarily lowered the DARM ugf and put a notch in, (which should cause anything like this).  He undid both changes when we saw the unusual noise, but the noise was unaffected by his change.  

We aren't going to investigate any further right now since the problem seems to have gone away.