I turned on some filters and gain in the SUS-MC2_MCL filter bank tonight so as suppress the seismic noise influence on MC_F. This may help the MC stay in lock in the daytime.
Koji updated the mcdown and mcup scripts to turn the MCL path on and off and to engage the Boost filters at the right time.
The attached PNG shows the MCL screen with the filters all ON. In this state the crossover frequency is ~45 Hz. MC_F at low frequencies is reduced by more than 10x.
I also think that this may help the X-Arm lock. The number of fringes per second should be 2-3x less.
Vacuum related work at atmosphere:
Atm1, Check all chamber dog clamps tightness with torque wrench,
Atm2, Replace old, black molibdenum disulfite bolts -nut with new silicon bronze nuts and clean SS bolts.
Atm3, Replace CC1 cold cathode gauges: horizontal and vertical.
Shasky day yesterday postpones venting. We had about 11 shakes larger than mag 4.0 Mag5.5 was the largest at 13:58 Sunday, Aug 26 at the Salton Sea area.
Atm3, ITMX and ETMX did not come back to it's position
It looks like we may lost 1 (or 3 ) magnets? Do not panic, it's not for sure
Rijuparna Chakraborty and Elli Elenora King received 40m specific basic safety training in the 40mLab
RGA scan, Maglev pumping speed at day 56
CC1 is dying. CC4 is real.
ANTS ALERT please watch out for ants. We have them in the control room.
1,PRM spot can be viewed directly from the window south-east of ITMX chamber. I can easy set up the mobile- Watek for this reason or you can just use an IR viewer.
Remember, we have 2 SOS centering targets ready to use , that Rana was suggesting.
2, PR2 spot centering can be viewed directly through window north-west of ITMX.
3, We should put back the BS view pick-up mirror for the vertical camera on the BS chamber and adjust its upper pick-up.
4, The BS centering can be viewed with the mobile-Watek placed inside the BS chamber immediately.
ETMX appears to be fine. It was stuck to its OSEMs in the usual way. I touched it and it dislodged and is now swinging freely. Damping loops have been re-engaged.
Earthquake m4.1 test for ETMX and moves ITMX. ITMX-LR sensor 0.3V
We installed beam targets on PRM and BS suspension cages.
On both suspensions one of the screw holes for the target actually houses the set screw for the side OSEM. This means that the screw on one side of the target only goes in partial way.
The target installed on BS is wrong! It has a center hole, instead of two 45 deg holes. I forgot to remove it, but it will obvious it's wrong to the next person who tries to use it. I believe we're supposed to have a correct target for BS, Steve?
The earthquake stop screws on PRM were too short and were preventing installation of the PRM target. Therefore, in order to install the target on PRM I had to replace the earthquake stops with ones Jenne and I found in the bake lab clean room that were longer, but have little springs instead of viton inserts at the ends. This is ok for now, but
We checked the beam through PRM and it's a little high to the right (as viewed from behind). Tomorrow we're going to open ITMX chamber so that we can get a closer look at the spot on PR2.
The two eye target for the BS is in the clean tool box. It actually has irises.
I tightened as many of the dog clamps on the bottom of the BS, ITMX and ITMY chambers as I could find. I used a torque wrench at 45 ft-lbs. Some of the bolts of the dogs were too long, and I couldn't find an extender thing to accommodate the bolt so I could reach the nut. None of the bolts moved that I was able to reach.
Steve, we're not doing final final alignment today (we will do it tomorrow), so please go around and double-check my work by checking all of the dogs first thing in the morning. Thanks.
Almost all chamber dog clamps on the floor checked. There are a few exception where it is impossible to to get to the nut.
Only the OOC nuts turned little bit. So our elastomer discs are holding up well. This means that the chamber anchoring to the floor is good.
Steve and Eric
Placed pick up mirror for BS face and PRM back. I will ask Jamie to clamp it.
There will be an other camera set up to view the face of PRM
The SOS centering target is 1.9 mm lower than it should be!
The hole is 10mm for the ~6 mm beam
We really need something better to replace the access connector when we're at air. This tin foil tunnel crap is dumb. We can't do any locking in the evening after we've put on the light doors. We need something that we can put in place of the access connector that allows us access to the OMC and IOO tables, while still allowing IMC locking, and can be left in place at night.
It is in the shop. It will be ready for the next vent. Koji's dream comes through.
I misaligned ITMX pitch on Friday and brought out the beam at 44" height. The beam was bouncing to much. I only realized it this morning why. The OSEM voltages are 1.8, 1.7, 0.2 and 0.9V Even with a stable 8-9 mm diameter beam you would be clipping
on the beam scanner 9 mm aperture. You can bring out the beam with one mirror right after PR3, just remove PRMOP2
We conducted a beam scan on the AP table of the AS beam. We used a lens to focus the beam onto a power meter, and slowly moved a razor blade across the beam using a micrometer, vertically and horizontally both in front of and behind the beam. We also had to block the beam next to the AS beam in order to do this, but is unblocked now. Mike will begin curve fitting the data to try and see if there is a different spot size given by the x-axis vs. the y-axis, and if the lens has any effect.
Eric Quintero and Mike Jenson received 40m specific basic safety training.
Summary: Recorded the presence of higher order modes in IMC
What I did: Misaligned the flat mirror MC1 by small amount in both pitch and yaw (it was needed to be done cause at the beginning of the experiment no higher order modes were present) and scanned the cavity for frequency-range 32MHz to 45MHz.
I found the presence of higher order modes around 36.7MHz (1st order) and 40.6MHz (2nd order) along with two other strong modes near 35MHz and 42.5MHz.
Please, restore condition after you finished and update elog right away! People wasted hours yesterday not knowing the condition of the MC
After looking at the in-vacuum layout I think we should make two changes during the next vent:
1) Reduce the number of mirrors between the FI and its camera. We install a large silvered mirror in the vacuum flange which holds the Faraday cam (in the inside of the viewport). That points directly at the input to the Faraday. We get to remove all of the steering mirror junk on the IO stack.
2) Take the Faraday output (IFO REFL) out onto the little table holding the BS and PRM Oplevs. We then relocate all 4 of the REFL RFPDs as well as the REFL OSA and the REFL camera onto this table. This will reduce the path length from the FI REFL port to the diodes and reduce the beam clutter on the AS table.
There is just so much room on this table.
24" diameter clear acetate access connector is in place. The 0.01" thick plastic is wrapped around twice to insure air and bug tight barrier for the MC to lock overnight. The acetate transmission for 1064 nm is 90 % This was measured at 150 mW 2.5 mm beam size.
SOS alignment tool with ID 9.5 and 6.3 mm
The SP table was found open this morning. Please, do not make optics dirty!
I cleaned up the tops of the SP table.
Stop storing your junk, boxes, laptops, etc. on the optical tables. This includes the big SP table. Please move all of that junk into racks or shelves, etc.
The IFO will be at atmosphere overnight. The annuloses are pumped down. The access connector jam nuts are tightened to 45 ft/lbs
Actual pumpdown will start tomorrow morning.
IFO P1= 1mTorr, CC1 = 5e-4 Torr. The IFO is ready for work. Be free to open the shutter and turn on HV
Jenne will double check the MC -REFL path for 1W power. There is a manual block on the PSL table.
Atm1, Pirani gauge at 9 h 10 min
Atm2, Pump configuration of pd#73 at 9h 35 min
The new cold cathode gauge CC1 is in place. We were at atmosphere for 28 days ......more later
[Koji, Steve, Den]
TT alignment is fine, yaw damping is satisfactory, pitch damping is slow. We might want to add magnets to the mirror and attach blades to the frame for pitch edge current damping.
We are moving towards electronics testing.
Atm1, TT 1.5" high adaptor base will be back from the shop in 10 days.
Atm2, There is no PITCH damping, YAW edie current damping works well at 0.5 mm gap
Atm3, Adjustable Al -disc that contains a small magnet is purely designed.
We have to come up with a solution to have damping in PITCH
Jenne, Mike and I installed all of the post holders we could today including: REFL11, REFL33, REFL55, AS55, MCRef, POX11 and POP55. We did not install AS110, POY or REFL165 because there are interferences that will require moving stuff around. We also did not mount POP22 because it is a peely wally ThorLabs PD that will be replaced by a strong, straight and right thinking LIGO PD in the fullness of time. We did move it out of the way however which is no more than it deserves. Next step this afternoon Mike and I will install all of the telescopes and launching hardware. Then with the help of Steve we will begin routing the fibers. The 1x16 splitter module will be here by next Monday, the laser by the following Friday and then we will light up the fibers.
I'm proposing split loom tubing that would run in the cable tray to protect the fibers inside of it. This tubing diameter in the cable tray can be 1.5-2" and out of the tray 0.75"
Where is IP-ANG ? It is good practice to use two mirrors at launching and detecting the beam, so you can walk it - precisely adjust it.
The window can be replaced at ~$1,500 ea. 10 weeks as optical quality BK7 with dual AR
cc1 = 2.3e-5 Torr at day 6 vacuum normal
This is the third morning in a row that the MC2 was tripped. Would you look at it Koji?
Den Martynov received 40m specific safety training.
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 SOS coil drivers (Atm2) were moved from 1X1 to 1Y2 location. Is this the best place to locate the IOO Tip-Tilt steering that will replace the PJ-PZT ?
See 40m wiki T-T
There had to be a power outage. Laser and air condition turned back on. The vacuum is OK
Sorensen DC power supplies were tripped, so they were reset: at AUX OMC South 18V and 28V for RF PS and at 1X1 24V
Power Outage confirmed:
** Notification **
CALIFORNIA INSTITUTE OF TECHNOLOGY
Date: Thursday October 04,2012
This morning at 2:17 a.m. much of the City of Pasadena including our Campus experienced a electric power sag of short duration, approximately 1/10 of a second. The cause was a fault on one of Pasadena’s 17KV circuits. Some sensitive equipment have been impacted.
Contact: Mike Anchondo x-4999
All the front end machines are back up after the outage. It looks like none of the front end machines came back up once power was restored, and they all needed to be powered manually. One of the things I want to do in the next CDS upgrade is put all the front end computers in one rack, so we can control their power remotely.
c1sus was the only one that had a little trouble. It's timing was for some reason not syncing with the frame builder. Unclear why, but after restarting the models a couple of times things came back.
There's still a little red, but it mostly has to do with the fact that c1oaf is busted and not running (it actually crashes the machine when I tried to start it, so this needs to be fixed!).
The RGA was not effected by the short power outage.
40 plus freshmen visited the 40m today
1) Mirror mount holder for "large silvered mirror" inside of the 8" OD tube vacuum envelope.
Aluminum sheet as shown will replace the acetate. Side entries for your arms and "window" on the top will be covered with acetate using double- sided removable-no residue tape 3M 9425
Tip Tilt pitch adjustment on existing-in vacuum suspension. This can be added by a simple installation of a 1.25" long 2-56 threaded rod with nuts.
We can only decide the need of pitch damping when the coils are activated.
VME crate blew its fuse and the fuse housing is hard to access.
Apparently all of the ION pump valves (VIPEE, VIPEV, VIPSV, VIPSE) opened, which vented the main volume up to 62 mTorr. All of the annulus valves (VAVSE, VAVSV, VAVBS, VAVEV, VAVEE) also appeared to be open. One of the roughing pumps was also turned on. Other stuff we didn't notice? Bad.
Several of the suspensions were kicked pretty hard (600+ mV on some sensors) as a result of this quick vent wind. All of the suspensions are damped now, so it doesn't look like we suffered any damage to suspensions.
CLOSE CALL on the vacuum system:
Jamie and I disabled V1, VM2 and VM3 gate valves by disconnecting their 120V solenoid actuator before the swap of the VME crate.
The vacuum controller unexpectedly lost control over the swap as Jamie described it. We were lucky not to do any damage! The ion pumps were cold and clean. We have not used them for years so their outgassing possibly accumulated to reach ~10-50 Torr
I disconnected_ immobilized and labelled the following 6 valves: the 4 large ion pump gate valves and VC1, VC2 of the cryo pump. Note: the valves on the cryo pump stayed closed. It is crucial that a warm cry pump is kept closed!
This will not allow the same thing to happen again and protect the IFO from warm cryo contamination.
The down side of this that the computer can not identify vacuum states any longer.
This vacuum system badly needs an upgrade. I will make a list.
Ayaka Shoda, visiting graduate student received basic 40m specific safety training today
ETMX optical table was left open. Burned toast award goes to ......?
PR1, PR2 and RP3 turned on for warming up for oil change. Oil changed with 3.2L of MVT-19 fluid in each. This substitute for HE-175 will be used at the next oil change - it has 1E-6 Torr vapor pressure.
To finish this job tomorrow: 1, check oil creeping upstream 2, change air filter of air purge if pressure drops <350 mTorr 3, measure venting time of pump