TITLE: 02/09 Owl Shift: 08:00-16:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 67Mpc
OUTGOING OPERATOR: Travis
CURRENT ENVIRONMENT:
    Wind: 1mph Gusts, 0mph 5min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.23 μm/s
QUICK SUMMARY: Locked for 28hours at 67Mpc. DARM looks a bit noisier in the bucket atm, but range doesn't look terrible, I'll investigate.

Current Road Conditions: Terrible. By far the worse road conditions I have ever had on a commute here. Route 10 and the bypass were managable, but on the 240 my traction control would have to kick in anywhere above 25mph just to go straight. I followed a snow plow for a bit and that was also sliding around at times. Please drive safely and let's hope conditions improve in the morning.

TITLE: 02/09 Eve Shift: 00:00-08:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 66Mpc
INCOMING OPERATOR: TJ
SHIFT SUMMARY:  Locked the entire shift and going on 28 hours now.  Judging by the 1/8 inch of ice on my car, it should be an exciting drive home.  Freezing rain continues and has picked back up since my mid-shift report.
LOG:  None

 

There have been 4 alarms about TCSY chiller low flow tonight, more frequent I would usually attribute to the known glitches.  See attached 12 hour plot.  It seems to be struggling a bit more than typical.

Observing for 24 hours.  Light freezing rain on site but seems to be tapering off.

J. Kissel

Using the canned function that produces the official sensitivity spectra for the public,
    /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/Common/Scripts/DARMASDs/produceofficialstrainasds_O2_C01.m
I grabbed the amplitude spectral density of DCS / GDS-CALIB_STRAIN and PCALY RX PD, with
    - C01 data from Dec 13 2016 @ 10:00 UTC for H1 (because CAL line heights have not changed all run) 
    - C00 data from Jan 30 2017 @ 10:00 UTC for L1 (because C01 isn't ready after Jan 24th, but L1 last changed line heights on Jan 27th)
and recast the calibration line heights into displacement amplitude (in [m_pk]) of all calibration lines as the stand currently in O2 for future reference.

The tables below lists the function of these lines, which actuator is used to drive the lines, the frequency, their amplitude in [cts] at the the drive point, and the amplitude it displaces the test mass at its given frequency.

H1:

Used To Characterize       C (f_s,Q_s)    A (K_TST)      A (REF)     A (K_PU)   C (K_C, f_cc)   C (f_cc, t_C)
Actuator                          PCAL          SUS         PCAL          SUS           PCAL             PCAL
Frequency [Hz]                    7.93         35.9         36.7         37.3          331.9           1083.7
Amplitude [drive ct]              5000         0.55          500         0.44           5000            15000               
Amplitude [m_pk]              4.78e-15     2.71e-17     2.21e-17     1.36e-19       2.71e-18         7.71e-19 

L1: (edit-- there are several errors in the table below. Will fix by the end of the day)

Used To Characterize                      A (K_TST)      A (REF)     A (K_PU)   C (K_C, f_cc)   C (f_cc, t_C)
Actuator                                        SUS         PCAL          SUS           PCAL             PCAL
Frequency [Hz]                                 23.3         22.7        331.3           23.9           1083.1
Amplitude [drive ct]                          0.052          400         0.08           7200            16160               
Amplitude [m_pk]                           2.87e-17     8.73e-20     2.55e-18       3.62e-17         5.42e-19

where the parameters of the sensing function, C, are as listed in T1600278, and the scalar gains in the actuation function, A, and described in T1500377.

On the conversion between raw [m] of each data stream into [m] of amplitude at the calibration line frequency: 
produceofficialstrainasds_O2_C01.m runs the matlab function pwelch over the time series of the data stored in the frames, 
     [ifo ':' subSystemTag '-CALIB_STRAIN' channelSuffix ]
     [ifo ':CAL-PCALY_RX_PD_OUT_DQ']
where subSystemTag is either GDS or DCS, and channelSuffix is either C00 or C01. I used all of the same pwelch/FFT parameters as are used normally in producing G1500623, except reducing the number of averages by a factor of 10 and increasing the frequency resolution, 
    nAvgs = 10;
    detrendOrder = 1;
    windowType = @hann;
    freqRes = 0.01; % [Hz]
    percentOverlap = 50; % %

Making sure that the chosen frequency resolution results in the calibration lines being bin-centered (I chose 0.01 [Hz] bin width), pwelch spits out a power spectral density in units of [(power)_{RMS} / Hz]. So to convert to (amplitude)_{pk}, I do the following (since, after a little pre-processing of the frame data, both channels are in start in [m]):
    sqrt( pwelch output ) * sqrt(ENBW) * sqrt(2)
where pwelch output is in [m^2/Hz], ENBW is the effective noise bandwidth for a Hann window (with normalized effective noise band width NENBW = 1.5) with a frequency resolution of 0.01 [Hz] i.e. ENBW = NENBW*f_res = 0.015 [Hz], and the sqrt(2) is to convert from RMS to Peak amplitude.

Added 100 mL H2O to Xtal chiller.  Diode chiller was good.  Filters look clean.

TITLE: 02/09 Eve Shift: 00:00-08:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 69Mpc
OUTGOING OPERATOR: Jeff/Patrick
CURRENT ENVIRONMENT:
    Wind: 20mph Gusts, 16mph 5min avg
    Primary useism: 0.07 μm/s
    Secondary useism: 0.22 μm/s
QUICK SUMMARY:  Observing for 20 hours.  Roads to the site weren't terrible, mostly slushy.  Route 10 must have been plowed recently as drifting wasn't apparent.  Snow has stopped falling.
 

TITLE: 02/08 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 66Mpc
INCOMING OPERATOR: Travis
SHIFT SUMMARY: Covered end of Jeff's shift. One GRB alert, otherwise quiet.
LOG:

21:38 UTC Ken to mid X
21:45 UTC Chandra and Kyle to mid Y
22:22 UTC Ken back
22:34 UTC GRB alert
23:09 UTC Chandra and Kyle back

Kyle, Chandra

CP4 did not complete auto fill today and timed out after 1 hour. We found that the electronic actuator has a layer of ice inside that leaked from the flex conduit (same issue that happened to two others over holiday break). We manually overfilled with 1/2 turn on bypass LLCV valve (after some manual overfill from control room). Total time was 30 min.

The actuator still works, so we disabled 24V power by disconnecting lead inside the actuator just to be sure that if/when the ice melts it doesn't short out the device. We will fix when the weather is more favorable. For now it's locked at 39% open.

Shift Summary: 18:11 (10:11) Received GRB alert, spoke to LLO Ops, both sites in Observing. In stand down until 19:11 (11:11). 20:30 (12:30) - Turning over to Patrick, as I need to leave for an appointment in town.   

Here are spectra from the several STS2 seismometers we have around the site, all are on the floor except BRS PEM:

HAM2-- Just +X of HAM2

ITMY-- ~+8m +X & +Y

ETMX-- ~3m -X of ETMX

ETMY-- ~3m -Y of ETMY adjacent to BRS Housing

BRS PEM (ADC_0_9[10]_OUT) sitting on table mounted to BRS base plate, see 33387 for images.

These spectra were all taken (except the one reference set) about 1137pst 7 Feb when the Site BLRMS show little wind tilt or EQ affects.

The reference traces on the PEM EY unit mounted with the BRS were before the centering I did 31 Jan.  See Krishna 33648 for the problems it had.  Sadly, my attempts to center it then and as of yesterday, power cycling it and more centering, has managed to center it but has not relieved it of the glitching started on 31 Jan.

Starting CP3 fill. LLCV enabled. LLCV set to manual control. LLCV set to 50% open. Fill completed in 32 seconds. TC B did not register fill. LLCV set back to 14.0% open.
Starting CP4 fill. LLCV enabled. LLCV set to manual control. LLCV set to 70% open. Fill not completed after 3600 seconds. LLCV set back to 39.0% open.

Ops Shift Transition: 02/08/2017, Day Shift 16:00 – 00:00 (08:00 - 16:00) - UTC (PT)

TITLE: 02/08 Owl Shift: 08:00-16:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 66Mpc
INCOMING OPERATOR: Jeff
SHIFT SUMMARY:
LOG: Still going for 12 hours, at 67 Mpc.

• 13:17 GRB
• 14:54 Richard, Ken to MY
• 15:15 Richard, Ken heading back.

All seems good. almost 9hours around 68Mpc.

TITLE: 02/08 Owl Shift: 08:00-16:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 66Mpc
OUTGOING OPERATOR: Travis
CURRENT ENVIRONMENT:
    Wind: 8mph Gusts, 6mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.38 μm/s
QUICK SUMMARY: Observing for 4 hours at 66Mpc. Roads clear on 240 and route 10, but a bit of snow in town.

PyCBC analysts, Thomas Dent, Andrew Lundgren

Investigation of some unusual and loud CBC triggers led to identifying a new set of glitches which occur a few times a day, looking like one or two cycles of extremely high-frequency scattering arches in the strain channel.  One very clear example is this omega scan (26th Jan) - see particularly LSC-REFL_A_LF_OUT_DQ and IMC-IM4_TRANS_YAW spectrograms for the scattering structure.  (Hence the possible name SPINOSAURUS, for which try Googling.)

The cause is a really strong transient excitation at around 30Hz (aka 'thud') hitting the central station, seen in many accelerometer, seismometer, HEPI, ISI and SUS channels.  We made some sound files from a selection of these channels :

• PEM-CS_SEIS_LVEA_VERTEX_Z (sped up by factor 4)
• PEM-CS_ACC_OPLEV_ITMY_X (sped up by factor 4)
• PEM-CS_ACC_BEAMTUBE_MCTUBE_Y (sped up by factor 2)

PEM microphones, interestingly, don't pick up the disturbance in most cases - so probably it is coming through the ground.

Note that the OPLEV accelerometer shows ringing at ~60-something Hz. 

Working hypothesis is that the thud is exciting some resonance/relative motion of the input optics which is causing light to be reflected off places where it shouldn't be ..

The frequency of the arches (~34 per second) would indicate that whatever is causing scattering has a motion frequency of about 17Hz (see eg https://ldvw.ligo.caltech.edu/ldvw/view?act=getImg&imgId=154054 as well as the omega scan above).

Maybe someone at the site could recognize what this is from listening to the .wav files?