The BLRMS are totally crazy today! I'm not sure what the story is, since it's been this way all day (so it's not an earthquake, because things eventually settle down after EQs). It doesn't seem like anything is up with the seismometer, since the regular raw seismic time series and spectrum don't look particularly different from normal. I'm not sure what's going on, but it's only in the mid-frequency BLRMS (30mHz to 1Hz).
Here are some 2 day plots:
Particle counts were measured inside the PSL enclosure at 40VAC variac setting.
Directly under HEPAs, on the east half of the optical table : 0.3 micron 20 particles / cu ft, 0.5 micron 0 p / cu ft, 0.7 micron 0 p / cu /ft
Away from the HEPAs, on the west edge of the op table: 0.3 micron 960 particles / cu ft, 0.5 micron 50 p / cu ft, 0.7 micron 20 p / cu ft
We may want to increase the RPM a little bit.
Checked our counters against recently calibrated Met One GT-526:
#1 is right on, #2 measured 25% less (it will go for calibration)
Flow bench at the south end : zero particle for all 3 sizes
IOO chamber particle logging measures 0.5 and 1 micron. Chamber opening limit is set to 10,000 particles max of 0.5 micron
At 10,000 p of 0.5 micron means ~100,000 - 180,000 p of 0.3 micron
We may have to lower the limit.
Its an increase in the microseismic peak. Don't know what its due to though.
Keven and Steve,
The 3 cranes tested and wiped off as preparation for upcoming vent.
Once you install a matlab newer than 2012a, you can install ligoDV as a matlab app and get the NDS2 client software for free. So you can easily get the 40m data from the outside world now and do the analysis on your own computer rather than login through nodus.
1)Power to the seismometers were turned down,
2)Guralp2 was moved to North side of POX table
3)Guralp2 was aligned in N-s Direction and leveled before connecting
4)Power to seismometers was turned on once Guralp2 was connected
An exercise of optimally subtracting one seismometer signal by another using weiner filters was done. Results have been summarized document attached.
I used MC_L signal from the Mode Cleaner as the desired signal with GUR2_X as witness signals. I observed good subtraction where coherence is high. But there was noise added in other frequency bands. I am not sure how to avoid that.
Please find attached documents that contains relevant plots.
Our fluorecent lights became obsolete. We'll have change fixtures over to some more energy efficient one. Do you have any recommendation regarding to less noise performer unit?
We may go this direction of LED fluorecent lamps ?
~Vancuver, Canada earthquakes: magnitude 6, 5 and more shaking
Local m3.8 eq shakes PRM lose.
After seeing all of these spikes in the BLRMS at high frequency for awhile, I power cycled the Guralp interface box (@ 10:21 PM) to see if it would randomly recenter in a different place and stop glitching.
It did - needs to be better centered (using the paddle). Plot shows how the Z channel gets better after power cycle.
How can we improve the cleanliness of the 40m IFO room 104 ? May be Mario Batali crocs if you chief chef of the lab likes it. We can do more effective things.
Atm 1 is showing the lab air quality dependence on outside air measured at the top of the IOO chamber. This made me to measure the differential pressure between lab and out side.
Properly sized air conditioner is over pressurizing it's room by 0.05 [" Water] like clean assembly room.
The 40m at Vertex location is barely getting pressurized to 0.01 " W
The control room is OK with 0.04 " W but it's air quality is very bad! It is 10x worse at 0.5 micron than IFO room.
Every entry from well pressurized control room into barely pressurized IFO pumps dirty air to our "clean room."
This door should be closed.
The drill- room entry is ideal because it is using the same air conditioner as the main lab, therefore it has cleaner air.
Things to do: seal holes of CES walls, seal paint wall at south end so it will shed less, replace gas kits on doors.
I have plugged the cable tray space entering the control room above Rosalba.
Probably more important is to establish quantitatively how particle counts affects the lock acquisition or noise in the interferometer.
We don't want to adopt a "Sky is Falling" mentality as was done previously in LIGO when people were trying to outlaw burritos and perfume.
Dust monitor counts and human noses do not correlate well with the interferometer's nose.
When the vacuum system is closed, we might check to see if particle counts correlate with losses in the PMC or excess scatter on the ISC tables. If not, we should move on to other concerns.
This was the second week without wet mopping the floor and wet wipe down of the vacuum envelope.
We changed filters on the 40m "HEPA" vacuum pump. It still has very dirty exhaust. Do not use it in clean room!
[Alan, Koji, Manasa]
Record number of 50 freshmen were given tour of the 40m this afternoon.
Sunday evening fireworks. Manasa heard it.
The 4th week of no wet mopping of the floor and no wet wiping the vacuum envelope.
We cleaned the intakes of the south arm IFO air condition. The bottom duct have quite a bit accumulation Atm1
See wet wiped contrast on Atm2
We found 3 holes around pipes ( coming from CES ) on the east wall that has to be sealed.
After closer examination of these holes, they are sealed off well.
As you may recall, Den designed some nice seismometer stations for us with the help of Steve. The granite base was installed : elog 8461. The point of these is to have nice solid bases for our seismometers to sit on, rather than the flimsy linoleum flooring. Also, they are covered (and will be insulated) to help prevent air currents and temperature fluctuations from affecting our seismometer measurements. Even though these seismometer stations have been in place for a few months, we are not yet taking advantage of them. This is a status elog, so that we know what needs to be done.
Recently, Den finished up the design for, and Steve ordered, and we received, the small aluminum plates that go on the side of the granite slabs, so that we can feed the connectors for the seismometer through the baseplate, in an airtight way.
The current plan is to use one Guralp at each end station, and the Trillium at the vertex. As of this moment, we have 1 Guralp at ETMY, 1 Guralp at ITMX, and a Streckeisen at ETMX, and the Trillium is sitting to the south of the POX table.
Most of the work that's left to do is just to place the seismometers on the new stations, and to make cables.
I have taken an inventory of all the things that I think we need to buy (or I need to find in the lab) in order for us to finish this project up.
We need to buy a LEMO connector for the T-240 plate.
We need to buy 6 O-rings: 3 to go between each aluminum plate and the granite slabs, the other 3 between the plate and the milspec connectors for the seismometer cables.
We need to buy or confirm that we have screws to attach the plates to the granite slabs.
We need to buy or confirm that we have screws to attach the milspec connectors to the plates.
I need to confirm that I have another 37-pin dsub for the Xarm Guralp cable, and a 25-pin dsub for the Trillium.
Assuming that I am reusing the existing Yarm Guralp cable, we have all the milspec connectors necessary.
I have a 30m long spool of 19-pair cable that I will use to make the Trillium cable. I have a long cable, formerly a Streckeisen cable, that I will cut the ends off of, and make into a Guralp cable. (We had 3 of these incredibly long, maybe ~50m cables - one became the Yarm Guralp cable, one is waiting to be the new Xarm Guralp cable, and the 3rd one is connected to the Streckeisen that we still have).
Work to be done:
* Make long cables for Xarm Guralp and Vertex Trillium. Check pinouts for the milspec -> dsub connections on each cable.
* Make small cables that go inside of the granite and seismometer station. These are to connect the sensor to the aluminum plate, and then the long cables go from the plate to the readout box. Unfortunately, the holes in the granite are not large enough to pass a connector through, so these will have to be soldered in-situ.
* Plug in the Trillium readout box and confirm that it's working / makes sense.
Longer term modifications and add-ons:
* Lemo connector with wiring for temperature and pressure sensors inside the vertex station. I believe that Den was looking into what sensors we might want.
* Needle valve for slow pressure equalization on vertex station (all stations should have this, but only the Trillium plate has a hole for this).
Is there anything else that I'm forgetting?? Please reply with thoughts.
I attach the drawings for Guralp and T-240/STS-2 connector plates. Drawings contain all information about the screws, O-rings and connectors.
Basically, box mounting receptacle for seismometer cable is attached to the connector plate with 6-32 screws. Inside cable should be ~ 1m long and connect the plate with seismometer.
For T-240 realization we have an additional LEMO connector for temperature and pressure monitoring inside the station. We should buy sensors and plug them into some machine with slow controls.
LEMO connector has 9 pins. 4 will be used for temperature and pressure sensors and spare 5 can be used for future ideas.
Also I think it might be better to put two T-240 into isolation stations.
It would be nice if we could use the existing seismometer cable and place a 2-terminal temperature sensor within the stainless-steel can. A device like the AD590/592 can drive current over a long cable run without pickup issues since its a current source. Inside of the seismometer breakout box we should make a circuit to scale the signal to be close to zero at 25 C and have a slope of 1 V/deg. There are example circuits in the application note - we can just make them on a piece of vector board and glue to the inside of the breakout box (where we connect to the regulated power).
This is not a test. Life can be dangerous in the 40m Control Room.
It looks like there was a 4.4 magnitude earthquake near Fontana, CA around 1:30am today. This tripped all of the suspension watchdogs, which Q has just now re-enabled.
Earth quake shake down yesterday Atm1
Atm2, today's shake
Please wet WIPE before opening chamber or optical table ! !
with methanol soaked kimwipes.
The Met One particle counter is located on CES wall, just behind ITMX chamber.
The numbers are not so bad, but have you ( ...a) asked the IFO lately?
The floor was cleaned under the east arm tube with hand held wet towel. We moved staff around and mopped. I did at the bottom of rack 1Y1, 2 and 3.
Last week we did the south arm tube floor.
Next week we 'd like to clean under rack 1X1,2,3, 4, 5, 6 and 7
1Y4, 1X1,2,3,4 & 5 instrument racks floor space were cleaned.
Last night we noticed an excess in the GUR1Z seis BLRMS on the StripTool. It was in the 0.1 - 0.3 Hz band. The rumor in the control room was that "this kind of noise has been showing up at night recently".
AS it turns out, this was not some environmental noise around the 40m at night, but instead its some internal servo oscillation in the GUR1 Z channel. In the Guralp seismometers, each channel is a different mechanical sensor (unlike the STS or T240), so when a single channel gets noisy it doesn't always implicate the others.
My guess is that the oscillation came from the Z channel needing to be recentered. I power cycled the interface box just now. The oscillation had already gone away, but I thought this might reduce the excess noise. Maybe it did, but the effect is tiny. You can see in the oscillation reference that the low frequency noise is high, but in the new trace its still kind of high. Needs to be re-centered correctly with the paddle. Or add a centering button to the interface box.
1X6, 1X7 and 1X9 instrument racks floor space were cleaned today
Please take a look at the table top with the flashlight before removing it. If it is dusty, wipe it down with dry lint free cloth in the box.
There is one box with flash light and wiper at AP, ETMY & ETMX optical tables.
Koji locked the MC, arms, and PRMI, with no troubles, after the M8.2 earthquake off the coast of Chile, that happened about 4 hours ago.
Atm2, Chilean 8.2M eq arrived to the 40m 16:57 in 10 minutes. Our OSEMs did not see them. Hanford got it 2 minutes later.
2 more earthquakes in Chile: a M6.4 and a M7.8.
We got them about 15 minutes ago (according to the BLRMS on the wall), but when I go tin, the MC was already locked, and engaging the LSC immediately got me PRMI lock (since that's the alignment state that the IFO was left in).
As payment for borrowing 2 of our seismometers, Zach has made us a new Trillium cable, to go from the granite station to the readout box, which we can put into 1X7, where the PEM ADC is. To put the T-240 in side the can, and seal it, we need a little jumper cable from the seismometer to the granite, but for now, we can just pass this cable underneath the can.
Keven and Steve,
We cleaned around the Vertex chambers, PSL and MC2 floor areas.
Our only seismometer is at the east end now.
Atm1, Ditch Day morning puzzle. The gardener came after the freshman did leave and cut the grass with the lawn mower.
Atm2, Yesterday afternoon the Aztecs containers moved out.
Yend seismometer isolation kit (elog 8461) hosts Guralp seismometer. I made a cable for inside connection, assembled the kit and relocated the instrument from its previous position at the yend inside the kit.
Seismometer is connected to the readout box and running.
Xend internal cabling and external connector is ready. We are waiting for seismometer from Gyro lab. We still need to fix the pot with clamps after we put the instrument in.
We also need a long cable from Xend to the guralp readout box.
Ant season has set in. I spotted and killed a few ants around the optics and the enclosure of the PSL table yesterday. TIme for our pest control crew to get busy!
Air condition maintenance will be finished by 11:30am tomorrow.
Yesterday, Kelvin mopped with chemicals the whole floor area of the lab. This was triggered by some visiting ants at our PSL last week. It was 6 months since we had the last fully wet mopped IFO floor.
The cleaning- mopping water became very dirty at the end.
The PSL HEPA was running at 30VAC-variac. It is 1 degree C warmer than usual. The HEPA fan motor turned up to 60 V
We had a look this morning at the status of the seismometer array, so that we can get it all put together. While we were looking at the Guralp at the Yend, we noticed that it was pointing the wrong way. The North-South nubbins were pointed East-West, so X and Y coming out of the seismometer were backward.
To fix the Yend's Guralp, we powered off the Guralp readout box, rotated the seismometer, re-leveled it, and then turned the power back on. Now X from the seismometer lines up with the X data channel, and similarly for Y.
The Yend Guralp has all of the cabling needed, and is installed on the granite slab. This seismometer doesn't need any more work for now. When we get around to it, we'll need to do some kind of thermal insulation, but other than that, it's good to go.
The Xend will also have a Guralp (Zach still has it in the Gyro lab for now). We have the long cable that should go from the readout box to the slab that we'll need to put into the cable tray. The short cable from the slab's plate to the seismometer is already in place. For this seismometer, we should just need to plop the instrument in place and lay the cable in the overhead cable trays. We should also remove the now obsolete STS-2 cable while we're doing that. So, the Xend seismometer station doesn't need too much work.
The corner station will need more work. Zach made for us the long cable, although he still has it in the Gyro lab, so when we get the seismometer and cable back, we'll need to lay that cable in the overhead trays. The short cable from the slab's plate to the seismometer does not exist yet. We want to make sure that we can feed the finished cable and connector through the hole in the slab, and then we'll solder it up out here on the EE bench. I think this is how Den was doing things. If not, we'll have to do the soldering in-situ, which we don't want. So, for the corner station, we need to make the short cable, lay the long cable, get the T-240 back from Zach and put it on the slab, re-install the readout box that Zach has, etc, etc. We should also make sure that the spaghetti pot fits on the slab, underneath the piece of metal that's sticking out over the slab. We think that it's the same amount of clearance that the Yend pot has, so it should be okay, but we'll check. The O-ring seems to be sitting on the MC2 chamber, so we should remember that.
Neither the Xend nor the corner station had the yellow dog clamps, so we'll have to figure out where Den / Steve have hidden them.
EDIT: We have checked, and the Guralp connector, which is larger than the Trillium connector, fits through the hole in the slab (with some disassembly), so we can solder together the short cable out here on the EE bench, and install it separately. Eeeeexxxxxcelllent.
We observed one or two ants climbing over PMC optics without booties and safety glasses.
The floor was mopped with strong Bayer Home Pest Control solution in the Vertex area.
Do not work inside the 40m lab if you are sensitive to chemicals!
The floor is mopped again with strong PEST CONTROL SOLUTION in water in the Vertex area.
Do not plane to work in the IFO-room till noon if you are sensitive to chemicals!
Ants are back on the PSL table. We'll be mopping the floor with pest control solution tomorrow morning.
The short cable from the slab to the sensor has been assembled and installed for the Trillium slab at the corner station. The corner still needs the sensor and the long cable, both of which are in use by the gyro experiment.
The STS-2 cable that was running to the Xend was pulled, and the new long Guralp cable that Den made was installed with help from Andres. The Xend just needs the sensor itself, which is also in use in gyro-land.
So, once we get the 2 seismometers and the one cable back from Zach, we should have 3 sensors nicely on the slabs that Den and Steve designed.
[Zach, Jenne, Steve]
This work happened on Tuesday. Bad Jenne for forgetting to elog it!
Zach brought the 40m's seismometers back (one Guralp and one T-240). We have set the seismometers on their slabs. Also, we ran the T240 cable from 1X5 over to the vertex slab. Also, also, Zach and Steve mounted the T-240 readout box in the 1X5 rack. We have not yet hooked it up to power, although there are fused power blocks available on that rack.
So, the T-240 box needs power, and then we need to connect the seismometers to their respective boxes. Also, we need to run medium-short BNC cables from the T-240 readout box to the PEM AA board over in 1X7.