Atm2 is before optical path adjustment. The idea was to remove possible clipping in vacuum.
Coherense significantly reduced below 4 Hz
Today I will replace the He/Ne laser 1125P with 1103P
I replaced the JDSU-Uniphase 1125P by 1103P He/Ne laser. This new laser had 2.8 mW output yesterday. It degraded to 0.5 mW by this morning.
The beam size on the QPD is ~3 mm This should give us better sensitivity. These are not the perfect lenses at all, but we have them here.
On the other hand, there are still some coherence below 1 Hz, so the laser intensity noise or clipping dominating this part of the spectrum.
ETMX oplev had 6 mm diameter beam on the qpd. I relayed the beam path with 2 lenses to get back 3 mm beam on the qpd
BRC 037 -100 Bi _concave lens and PCX 25 200 VIS do the job. Unfortunately the concave lens has the AR 1064.
Sorry Kiwamu, I realized too late that you were freeswigging. Hopefully 4 hrs was enough.
Coherence at 1 and 2-3 Hz only. He/Ne laser intensity noise is not an issue.
Uniblitz mechanical shutter installed in the green beam path at ETMY-ISCT The remote control cable has not been connected.
The ETMY shutter can be remotely switched from medm screen POY of mechanical shutters.
The new cable from ETMY controller goes to east vertex EV-ISCT where it is connected to POY shutter hook up BNC cable.
First aid kits are located close vicinity of entry doors and under circuit breaker panels.
Thinks to do before the NEXT realignment:
B, tie 4 ancher bolts on table legs to the floor
C, tie 4 dog clamps between table and chamber
D, check the locked position of the 4 x 4 positioning screws
E, check bellow protecting 4 tubes are not shorting
A, here is the concrete slab cut
It reminds me to check the IFO vacuum envelope dog clamps on the chambers to floor with torque wrench.
In order to move the emergency shut off switch in room 103 I had to turn off the 2 W Innolight laser. This job will take an hour.
It is back on.
CALIFORNIA INSTITUTE OF TECHNOLOGY
UTILITY & SERVICE INTERRUPTION
Building: Central Engineering Services (C.E.S.)
LIGO Gravitational Physics building adjacent to C.E.S.
Safety Storage adjacent to CES
Date: November 19, 2011
Time: 8:00 a.m. To 9:00 a.m.
Contact: Mike Anchondo ext. 4999 Tom Brennan 4984
*This interruption is required for maintenance of high voltage switchgear in Campus Sub Station.
CANCELLED, WILL BE RESCHEDULED*
I was lucky to notice that the nitrogen supply line to the vacuum valves was leaking. Closed ALL valves. Open supply line to atm. Fixed leak.
This was done fast so the pumps did not have to be shut down. Pressurized supply line and open valves to
"Vac Normal" condition in the right sequence.
The PMC HV drops off more offen lately.
Shade 12 black glass-green lines: 1/8" thick, 6" wide x 7 " high mounted on angle bracket below. Aperture 1" diameter. Let me know what do you think.
I locked the PMC and MC resonated in TM00 right on. Than I started checking anchoring screws with the torque wrench.
B, 3/8 foor bolts were tight, They were set to 50 ft/lbs
C, dog clamp bolts were tight at 80 ft/lbs
D, horizontal position locks were lose. They were locked by finger.
E, below covers were reset not to short
The MC is locking in TM01 mode now
They were traced and labeled. One goes to 1X2 and the other to AS-ISCT. They are Andrew Heliax 1/4" od. made by CommScone, model number FSJ1-50A
The PMC acted like it was sleeping. The HV slider was dead. The MC locked instantly as the PMC had transmission.
The Nov.19 interruption was rescheduled to be on Nov.20,2011
CALIFORNIA INSTITUTE OF TECHNOLOGY
UTILITY & SERVICE INTERRUPTION
Building: CENTRAL ENGINEERING SERVICES, STEELE HOUSE, KECK LAB,
LIGO GRAVITATION PHYSICS BLDG, SAFETY STORAGE (BY CES)
Date: Sunday, Nov. 20,2011
Time: 10:00 AM TO 11:00 AM
Contact: MIKE ANCHONDO X-4999 OR TOM BRENNAN X-4984
*THIS INTERRUPTION IS REQUIRED FOR MAINTENANCE OF HIGH VOLTAGE SWITCHGEAR
IN CAMPUS SUB-STATION.
I'm looking for an ether net based power switch for turning lights on and off for the vacuum system from MEDM screen. This is what I found
Jamie please take a look at it.
I installed 4 remote AC power on/off strip at
1Y1 for the Vertex area 4 chamber illuminating lights ( CIL )
1Y3 for HV ps for PZT steering mirrors that should be interlocked with P1 pressure gauge. Power off above 3 mTorr
1Y4 for ETMY CILs,
1X9 for ETMX CILs
I need one volunteer to help me to make MEDM screen and connect the network to the switches.
The ETMX oplev returning beam is well centered on the qpd. We lost this signal 2 days ago. I will check on the qpd.
ETMX sus damping restored. c1iscex computer is down
The foreline pressure of TP2 was 1.4 Torr this morning. This drypump worked well for ten months.
Recently rebuilt drypump with new seal was swapped in.
This is how you do it: close V1, V4 and turn off TP2. Replace drypump and start up TP2
Set pump speed to 50 K rpm and open V4 to TP1 Note that the Maglev was not turned off because V4 was closed off only 5-10 minutes.
Open V1 the status is Vac Normal.
TP2 is rotating at 50K rpm, current pick up 0.2A, the temp is 26C and its foreline pressure 33 mTorr
Ben and Sam came over to fix one of the east side sliding door sensor that had to be moved from the inside to outside on the enclosure.
We turned off the 2w Innolight for 20minutes. The power is back on, the PMC and MC locked itself immediately.
This moring I centered the IOO Angle QPD. The IOO Pos QPD was not centered. The existing layout does not allow the beam centering of the Pos qpd without misaligning the MC
input. We have to add an aditional steering mirror. I will do that tomorrow morning.
I added the steering mirror for Pos and centered both qpds
The PRM lost damping about a day ago. It was restored.
C1:IOO-QPD_ANG_VERT beam movement in 1 degree C temp change in 3 hrs
Our existing 300 series SS plungers from McMastercar #8476A43 are silver plated as Atm2 shows.
Problems: 1, they become magnetized after years being close to the magnets
2, they oxidize by time so it is hard to turn them
I looked around to replace them.
Titanium body, nose and beryllium copper spring. None magnetic for UHV enviorment.
Can be made in 7 weeks at an UNREASONABLE $169.00 ea at quantity of 50
The vacuum is ready for no AC power for 1 hr on Sunday morning at 10am
I did the follwing:
Closed V1, stopped the rotation of TP-1 maglev, waited till it reached 0 Hz_ rpm and turned it's controller off.
Closed V4 and stopped TP-2 rotating
Closed all annuloses and VA6
Closed VM1 and opened VM3 This means the RGA is being pumped by TP3. RGA is running in background mode. V5 will close instantly as the AC will be turned off.
VAC STATUS: IFO envelope and annulosses are not pumped. P1 pressure will reach 5-6 mTorr by Sunday morning.
The PSL output shutter will be closed by the interlock at 3 mTorr
Kiwamu will turn off Piezo Jena PZT power supplies and computers Saturday.
I will be here around 1pm Sunday to star pumping. I will need EPICs MEDM running by than.
State condition: Vac Normal, CC1 ~8e-6 Torr
The IFO pressure peaked at 8.3 mTorr after 2days of not pumping.
Here is 5 days of trend of the EOM temp sensor and the heater driver monitor. Unfortunately, it looks like we're regularly railing the heater. Not so awesome.
Can you zoom the temp mon? (V= -0.1 ~ +0.1)
The crystal was too cold and I tried to heat the PSL table by the lighting. But it seemed in vain.
It is not working
It is not obvious what is working.
Santa Anna wind speed was locked around 60 kmph last night on campus. The strongest in 30 years. The lab hold up well. We did not lose AC power either.
Threes and windows were blown out and over on campus.
We have 4 sliding glass windows without "heavy-laser proved" inside protection.
We should plan to upgrade ALL sliding glass windows with metal protection from the inside.The strongest in 30 years.
The existingly used used Pasternack Enterprices RG58 C/U cable lenght ~ 140 ft and the specs are here at Atm1
Atm2 The performance grade RG58-P coaxial cable specs.
3/4 " thick colored acrylic material will be used in this air tight design. Surgical tubing for o-ring. We may have to put an o-ring into the bottom to have it really air tight.
The top drawing is not ready. It will have handle and industrial grade L-handle lock pin to hold cover down. There will be 2 one inch od post in the midle of the table to hold the cover and lock the ball pin.
I'm waiting for your inputs, so I can send this preliminary design out for quote.
Is there a reason the framebuilder status light is red for all the front ends?
Also, I reenabled PRM watchdog.
Apparently there is a bug in the timing cards having to do with the new year roll-over that is causing front-end problems. From Rolf:
For systems using the Spectracom IRIG-B cards for timing information, the code did not properly roll over the time for
2012 (still thinks it is 2011 and get reports from DAQ of timing errors (0x4000)). I have made a temporary fix for this
in the controller.c code in branch-2.3, branch-2.4 and release 2.3.1.
I was going to check to see if the 40m is suffering from this. I'll be over to see if that's the problem.
The problem is the same as yesterday.
Dataviewer is recovered after heavy new year party.
ETMX sus damping restored
On Tue, Dec 20, 2011 at 11:37 PM, Rana Adhikari wrote:
We are thinking of replacing a few metal parts in the suspension with sapphire/ruby. We want to replace the standoff (which is Al) with sapphire and also the top plate where the wire is clamped.
For the top, we should make a cutout for a little plate in the existing crossbar. In the cutout would go a little mounting plate. Then the clamping plate (which is now steel) we would also replace with a Sapphire one.
I don't think it matters whether its sapphire or ruby, just has to be very hard.
Can you please get some quotes on the parts?
The present plan to go with clear cast acrylic plexiglass 1" thick side wall and two clear 1/2 thick top cover.
The inside would be lined with light braun YAG safety window sheets 0.14" VLT ~25% OD 4 @ 532nm & OD 5 @ 1064nm
Transparent- clear plexyglass from tree different sources were measured in 1064 and 532 nm light.
Samples: a, clear Acrylic-GP 0F00 from Ridout Plastics in thickness 0.7" , made by Evonic Ind
b, clear cast acrylic from Mc Master Carr in thickness 0.94" , likely made by Reynolds-Cast
c, clear cell cast plexyglass from Delvie's Plastics - Utah in thickness 0.93" , maker not known
PMC reflected beam was used at 92 mW and 6 mm diameter at incident angle 0-25 degrees.
All tree samples agreed on Transmittance of ~90%, Reflectivity ~3-4% and calculated Adsorption ~6-7%
Transparent Colored Acrylic orange-amber #2422 from www.eplastics.com in 0.12" thickness gave T 96%, R 1% and Ab-calc ~3% in the beam of 92 mW 1064 nm at 6 mm diameter.
Transparent , colored Light Red #26 thin film filter policarbonate-polyester 0.002" thick from Roscolux measured T 81% of 115 mW 1064 nm
Now I changed power meter FieldMate to Ophir and the light source to laser pointer 2.2 mW ~532 nm with 1-2 mm beam diameter.
Orange - amber #2422 sample, 0.12" thick, T 1% , R 4% and Ab-calculated ~95%, estimated visibility ~50% It does cut out the green at this low power level.
Light red #26 sample T 0.5% at 2.5 mW of 532 nm . The transparent green is not visible. The softening point of this sandwiched polycarbonate-polyecter filter is 160C. Estimated VLT of this film ~40%
Clear and colored acrylics' @ 1064 nm transmittance 90% or higher regardless of thickness. Softenig point 115 degrees C
Colored acrylic and colored policarbonate film are adsorbing the low power green and they transmit the 1064nm beam.
Options to consider: a, acrylic laser safety shield liner of 0.125" thick inside of 1" thick clear acrylic box, OD +5 @1064 and OD +4 @ 532nm, amber color VLT 27%, 150$/sqft
b, thin metal liner for 1" wall acrylic box, VLT 0%
I placed an other Y2-LW-1-2050-UV-45P/AR steering mirror into the beam path of the green beam launching in order to avoid the ~30 degrees use of the 45 degrees mirror. The job is not finished.
It started with fire alarm test yesterday at 14:50 All alarms are functioning VERY loud and their flashers are bright. Evacuation drill followed. We assembled at north west corner of the 40m building and counted 6 heads.
Nobody was left sleeping inside. Bob carried the success report of the drill to PMA office immediately.
The alignment is finished after the realization that the 3rd steering mirror had to be adjusted too.
The input power increased from 1.2 to 1.4 mW
In order to get a better price from Vlier's Tom Chen I changed Ti body back to SS304L-siver plated and music wire spring. The price is still ~$120 ea. at quantity 50
I will talk to Mike G about modifying the McMaster plunger with a hex nut.
I have realigned the beam pointing to PMC. The transmitted light increased from 0.74 to 0.83.
The misalignment was mainly in pitch.
The PMC pointing has changed, so MC is resonating in high order modes.
Roscolux filter films #74 night blue, 0.003" thick and #26 light red, 0.002" thick were measured in the beam path of ~6 mm diameter, 1W 1064 nm .
T 90% + - 5% at 0-30 degrees of incident angles and R ~10 %
These sandwitched thin films of policarbonate-polyester filters are not available in thicker forms. Rosco is recommending them to be cooled by air if used in high power beam.
These filters did not get warm at all in 1W, so absorption must be very small.