ID |
Date |
Author |
Type |
Category |
Subject |
6263
|
Thu Feb 9 16:46:02 2012 |
steve | Update | SUS | ALL oplev YAW transfer functions |
Quote: |
SUS- BS, ITMX, ITMY, PRM, SRM, ETMX & ETMY_OLPIT transfer funtion with sine wave excitation 0.1 amplitude:
|
OL_YAW transfer functions are here.
I had two PHDs helping me to overlap the EXML files in DTT. We failed. This job requires professorial help. |
6264
|
Thu Feb 9 17:11:05 2012 |
steve | Update | SUS | more OSEM problems |
These observations of the OSEMs were taken while taking transfer functions of oplev YAW at excitation amplitude 0.1
Atm1, C1:SUS-ETMX_SENSOR_SIDE cross coupling
Atm2, C1:SUS-ITMX_SENSOR_LL not excitable
Atm3-4, BS and PRM insensitive
Good OSEM list: ITMY, ETMY and SRM
|
6268
|
Fri Feb 10 11:01:31 2012 |
steve | Update | IOO | crazy ground motion |
Quote: |
I gave up tonight's locking activity because the MC can't stay locked.
It seems that somehow the seismic noise became louder from about 1:00 AM. 
I walked around the outside of the 40-m building to see what's going on, but no one was jumping or partying.
I am leaving the MC autolocker disabled so that the laser won't be driven crazy and the WFS won't kick the MC suspensions.
The attachment is a 3-hour trend of the seismometer outputs and the MC trans.

|
Something has started shaking last night. Everybody is claiming to be innocent next door.
I turned off the 40m AC at 11:06 |
6269
|
Fri Feb 10 11:46:44 2012 |
steve | Update | IOO | seismic noise back to normal |
The shaking has stopped at 9:32am The AC was turned back on at 11:30am We still do not have any explanation
|
6270
|
Fri Feb 10 15:46:59 2012 |
steve | Update | SUS | ruby wire standoff |
Finally I found a company who can do Koji's improved -hard to make- specification on ruby or sapphire wire standoff.
NOT POLISHED excimer laser cut, wire groove radius R 0.0005" + - 0.0002" 
$250 ea at 50 pieces of order |
6273
|
Fri Feb 10 15:54:27 2012 |
steve | Update | PEM | AC turned back ON |
The air cond was off for 2 hrs. I just switched it back on at 15:51 |
6278
|
Tue Feb 14 08:22:27 2012 |
steve | Update | SUS | sus damping restored |
ITMX, PRM and BS watchdogs are tripped. They were restored.
Stable MC was disabled so I can use MC_REFL 1 W beam to measure green glass . |
6280
|
Tue Feb 14 17:09:05 2012 |
steve | Update | General | reflectivity of green welding glass |
Schott, Athermal green welding glass, shade #14 reflectivity was measured in 1.2W, ~1 mm diameter beam of MC reflected.
The P polarization measurement was done with the help of half wave plate and PBC
|
6282
|
Wed Feb 15 11:34:01 2012 |
steve | Update | | under the shouth end optical table |
I added an U channel based bottom shelf at the south end today. |
6288
|
Thu Feb 16 09:59:16 2012 |
steve | Update | ASC | IP- ANG |
Initial pointing or IP-ANG is a pointing monitor of the MC. This beam is launched after the second pzt steering mirror.
IP-ANG is missing the pick up mirror by a few inches at ETMYchamber
1000 days plot show last appearance in Feb 2010 |
6299
|
Tue Feb 21 08:33:16 2012 |
steve | Update | Green Locking | periscope adapter plate |
Two extender plates ready for cleaning. The existing optical table tops have 38" OD. Using two of these the OD will be 44" |
6308
|
Thu Feb 23 09:09:33 2012 |
steve | Update | SAFETY | safety checks |
Emergency exit lights were inspected: 2 out of 13 batteries have to be replaced
One of the Halon fire extinguishers needs to be recharged out of 8
Please do participate in preparation for the upcoming safety audit on Feb 28 |
6309
|
Thu Feb 23 10:53:54 2012 |
steve | Update | SUS | oplev PIT transfer functions |
Oplev transfer functions PIT UGF were optimized to be at 2-3 Hz with 60 degree minimum phase margin by adjuting oplev gains.
Additional Notes by KI:
- The PRM oplev has a tailored 3.3 Hz resonant gain in order to calm down a wobble during the lock acquisitions.
- Also in the PRM oplev a 35 Hz elliptic cut-off filter wasn't activated at the time when Steve measured it.
- In both ITMs, elliptic cut-off filters seem to have higher corner frequencies compered with the others.
- I guess these settings are from the old days.
- ETMs and ITMs have whitening filters while the rest of the suspensions don't.
- Without the whitening filters, normally the signals above 30 Hz are covered by some electrical noises or perhaps He-Ne laser intensity noise (#5630).
- This is why we usually use the 35 Hz elliptic filters to roll off the control noises.
- Since the ETMs and ITMs have whitening filters they potentially can have slightly higher corner frequencies in the elliptic filters.
- Of course the corner frequencies need to be re-designed in terms of the amount of noise injection to the longitudinal motion.
|
6312
|
Fri Feb 24 08:06:52 2012 |
steve | Update | SUS | sus restored |
Quote: |
The following optics were kicked:
MC1 MC2 MC3 ETMX ETMY ITMX ITMY PRM SRM BS
Fri Feb 24 04:11:15 PST 2012
1014120690
Steve (or anyone), can you restore the watchdogs when you come to the lab in the morning ?
|
Kiwamu (or whoever is here last tonight): please run the free-swing/kick script (/opt/rtcds/caltech/c1/scripts/SUS/freeswing) before you leave, and I'll check the matrices and update the suspensions tomorrow morning.
|
|
All suspentions were restored and MC locked. PRM side osem RMS motion was high.
Atm2, Why the PRM is 2x as noisy as the SRM ? |
6322
|
Mon Feb 27 10:21:37 2012 |
steve | Update | SAFETY | safety audit tomorrow morning |
Quote: |
Emergency exit lights were inspected: 2 out of 13 batteries have to be replaced
One of the Halon fire extinguishers needs to be recharged out of 8
Please do participate in preparation for the upcoming safety audit on Feb 28
|
Batteries replaced and cylinder recharged. Please clean up your experimental set up if it is blocking breakers or entry way etc.
I will start the final clean up 2pm today.
|
6323
|
Mon Feb 27 14:35:22 2012 |
steve | Update | SUS | oplev YAW transfer functions |
The BS and the PRM have 3.3 Hz resonant gain filters that kill the phase margins.
|
6329
|
Tue Feb 28 11:20:51 2012 |
steve | Update | SAFETY | safety audit 2012 |
Correction list by visiting safety committee, Haick Issaian is not shown:
1, update laser, crane operator list and post it
2, check fire extinguishers monthly, date and initials must be on the tags
3, move drinking water tower so it does not block fire extinguisher
4, post updated crane doc at cranes
5, post present phone lists at IFO room phones
6, emergency laser shutoff at the south end must be mounted without C-clamp
7, use heavy cable tie to insure position of mag-fan on cabinet top
Additional to do list:
a, safety glasses to be cleaned
b, let the electrical shop fix Rack-AC power to optical tables at the ends
c, measure transmission of laser safety glasses
d, update IFO outside door info signs
e, update laser inventory and post it
f, schedule annual crane inspection and renew maintenance contract
g, PSL enclosure inner shelf needs a good clean up so it is earthquake safe
|
6344
|
Thu Mar 1 09:26:50 2012 |
steve | Update | SUS | SOS baffle plates are ready |
Green welding glass 7" x 9" shade #14 with 40 mm hole and mounting fixtures are ready to reduce scatter light on SOS
PEEK 450CA shims and U-shaped clips will keep these plates damped.
|
6370
|
Wed Mar 7 11:20:23 2012 |
steve | Update | SUS | oplev qpd offsets zeroed |
All oplev qpd quadrons were zeroed by offset in blocked dark condition. |
6389
|
Fri Mar 9 10:17:06 2012 |
steve | HowTo | PEM | do not leave tables open |
Type: How not to
Please do not leave optical tables open! You will be held responsible for creating dirty optics. |
6390
|
Fri Mar 9 10:44:57 2012 |
steve | Update | RF System | OSA |
Optical spectrum analyzers like the Attachment made by Coherent , Meles Griot- CVI and Spectral Product are all discontinued.
The 40m have Coherent models C240 analyzer with controller C251 Their Finesse measured in 2004: sn205408 F302, sn205409 F396,
Jenne borrowed Jan's Meles Griot model 13SAE006, Peter King has the same model. FSR 300 MHZ, finnees 200 minimum |
6395
|
Fri Mar 9 16:00:46 2012 |
steve | Update | Green Locking | laser emergency shut down switch replaced at the south end |
Over-sized local laser emergency switch was held by large C clamp at the south end. This was replaced by a smaller one and it is mounted with magnets.
The Innolight laser was turned off, while the interlock was wired. |
6413
|
Wed Mar 14 10:06:26 2012 |
steve | Update | Green Locking | dichroic mirror quotes |
Dichroic mirror quotes are in the wiki.
ATF is pricy.
We got a good price from Laseroptik, but the wedges are 5 arcminutes. The fused silica grade is 0F, meaning the homogeneity is 5 ppm instead of 1ppm. I requested an other large wedge quote on the substrates.We may have to get substrates from somebody else and ship it to Germany
MLT quote is outrageously high
REO is not interested in this low volume job.
|
6429
|
Tue Mar 20 09:59:01 2012 |
steve | Update | IOO | Laser tripped off |
Today is janitor day. It still does not explain why the 2W Innolight tripped off about an hour ago. All back to normal.
.......................................................I asked Keven later, he admitted hitting the emergency shut off next to the chemical storage cabinet. |
6430
|
Tue Mar 20 16:53:48 2012 |
steve | Update | PEM | cranes maintenance & certified inspection of 2012 |
Fred Goodbar of Konecrane has completed the annual certified crane inspection and maintenance of our cranes as required in safety document.
They are in good working condition and safe to use. |
6432
|
Wed Mar 21 10:31:28 2012 |
steve | Update | SAFETY | AC power to ETMY turned off |
ETMY sus damping was disabled. Green locking laser and associated electronics turned off. Computers and power supplies turned off at rack 1Y4
The electricians picking up ac power from 1Y4 manual disconnect box and installing conduit line to ISCT-ETMY east end optical table.
There will be no more daisy chaining this way. |
6433
|
Wed Mar 21 11:32:47 2012 |
steve | Update | SAFETY | AC power to ETMX turned off |
Quote: |
ETMY sus damping was disabled. Green locking laser and associated electronics turned off. Computers and power supplies turned off at rack 1Y4
The electricians picking up ac power from 1Y4 manual disconnect box and installing conduit line to ISCT-ETMY east end optical table.
There will be no more daisy chaining this way.
|
The power is back on at ETMY . c1iscey has not been restarted.
Now I'm turning ac power off at ETMX for the same job to be done. |
6434
|
Wed Mar 21 19:12:27 2012 |
steve | Update | Computers | AC power back on both ends |
Quote: |
Quote: |
ETMY sus damping was disabled. Green locking laser and associated electronics turned off. Computers and power supplies turned off at rack 1Y4
The electricians picking up ac power from 1Y4 manual disconnect box and installing conduit line to ISCT-ETMY east end optical table.
There will be no more daisy chaining this way.
|
The power is back on at ETMY . c1iscey has not been restarted.
Now I'm turning ac power off at ETMX for the same job to be done.
|
The power was turned back on at 4pm It took some time for Suresh to restart the computers. We have damping but things are not perfect yet. Auto BURTH did not work well. |
6435
|
Thu Mar 22 08:14:21 2012 |
steve | Update | Green Locking | dichroic mirror quotes with large wedge |
Quote: |
Dichroic mirror quotes are in the wiki.
ATF is pricy.
We got a good price from Laseroptik, but the wedges are 5 arcminutes. The fused silica grade is 0F, meaning the homogeneity is 5 ppm instead of 1ppm. I requested an other large wedge quote on the substrates.We may have to get substrates from somebody else and ship it to Germany
MLT quote is outrageously high
REO is not interested in this low volume job.
|
The Laseroptik quote is here.The 2 degrees wedge cost is $40 on each optics! See wiki |
6469
|
Fri Mar 30 08:58:37 2012 |
steve | Update | SAFETY | Safety glasses checked |
Bob cleaned all safety glasses in 10 % Liquinox soap in water solution first. The transmittance of glasses were checked at 100 mW 1064 nm S polarization, beam diameter 0.5 mm at 0-20 deg incident.
Coherent FieldMate power meter measured T= < 1 mW of all glasses. |
6470
|
Fri Mar 30 09:37:13 2012 |
steve | Update | SAFETY | safety audit 2012 CORRECTIONS |
Quote: |
Correction list by visiting safety committee, Haick Issaian is not shown:
1, update laser, crane operator list and post it
2, check fire extinguishers monthly, date and initials must be on the tags
3, move drinking water tower so it does not block fire extinguisher
4, post updated crane doc at cranes
5, post present phone lists at IFO room phones
6, emergency laser shutoff at the south end must be mounted without C-clamp
7, use heavy cable tie to insure position of mag-fan on cabinet top
Additional to do list:
a, safety glasses to be cleaned
b, let the electrical shop fix Rack-AC power to optical tables at the ends
c, measure transmission of laser safety glasses
d, update IFO outside door info signs
e, update laser inventory and post it
f, schedule annual crane inspection and renew maintenance contract
g, PSL enclosure inner shelf needs a good clean up so it is earthquake safe
|
Completed with the exception of d and g |
6472
|
Fri Mar 30 10:24:14 2012 |
steve | Update | SUS | new OSEM locking plunger |
Quote: |
Quote: |
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
|
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.
|
Conclusion: There is no need to silver plate the SS plunger at the torque level we hold the OSEMs
Mike Gerfen will be done with 50 pieces by April 4 and he will give them to Bob for cleaning. They should be cleaned and baked in a jig so the springs would be compressed for better venting. |
6473
|
Fri Mar 30 17:37:09 2012 |
steve | Update | General | cutting green welding glass for beam dumps |
Quote: |
Schott, green welding glass, shade 14, 3 mm thick was measured in the beam path of 1.2W, S polarization of 1064nm at ~1 mm diameter size as MC reflected path.
Absorption 95%, R 5% at incident angle 25-50 degrees. It looks like the perfect material for beam trap.
|
The CIT Chemistry Glass Shop cuts turned out to be sloppy using diamond disc blade cutter.
East coast Precision Glass & Optics offered scribed cut and polished side. Their quote price was high and time consuming.
The GLASS HOUSE shop in Pasadena 626 / 796-9151 on Walnut did a good and cheap job. Oscar the cutter will finish the rest of the cutting by next Friday, April 6
He used scribed cutting technic and his 1" x 0.5" pieces are good. Bob will pick up them up. |
6558
|
Tue Apr 24 09:58:37 2012 |
steve | Update | PEM | earthquake 3.9 magnitude |
Local eq shakes the lab |
6559
|
Tue Apr 24 11:27:51 2012 |
steve | Update | PEM | new chairs |
We received 6 new chairs stools for the work benches that have 36" heights.
The control room east side and general office desks require 18" seat height. The new chairs stools have minimum seat heights 26"
Please label chairs that we are getting rid of.

|
6571
|
Thu Apr 26 09:22:17 2012 |
steve | Update | | under the east end optical table |
Quote: |
I added an U channel based bottom shelf at the south end today.
|
I'm working on similar shelf at ETMY. Precondition: NPRO in bypass mode, heater for doubling in bypass........since power outage? Optical level servo turned off.......
U-channel based shelf in place. Oplev servo is back on at 11:15am The table may moved. The oplev return is missing the quad by a few milimeter. |
6577
|
Fri Apr 27 08:11:19 2012 |
steve | Update | CDS | c1ioo condition |
|
6643
|
Mon May 14 08:49:47 2012 |
steve | Update | SUS | ETMY damping restored |
ETMY sus damping restored. |
6644
|
Tue May 15 08:44:55 2012 |
steve | Update | SUS | ETMX damping restored |
ETMX sus damping restored |
6647
|
Wed May 16 14:06:49 2012 |
steve | Update | SUS | Temperature rules |
Guralp 1 is on the south side of IOO chamber |
6648
|
Thu May 17 15:31:22 2012 |
steve | Update | General | beam trap posts & clamps for vacuum |
Aluminum posts and SS clamps for green glass traps in vacuum will be out of the shops by June 6, 2012 the latest
|
6649
|
Fri May 18 11:19:17 2012 |
steve | Update | SUS | ETMY oplev laser is dead |
The typical sign of a dying gas laser is that it glows for a few minutes only. The power supplies are fine.
Two new JDS - Uniphase 1103P lasers ( NT64-104 ) arriving on Monday, May 21 |
6650
|
Fri May 18 15:25:15 2012 |
steve | Update | SUS | AR coated lens swapped in at ETMX oplev |
Quote: |
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.
|
The uncoated bi-concave lens was replaced by AR coated one: KBC 037 -100 AR.14 resulting 35% count increase on qpd |
6652
|
Mon May 21 07:45:39 2012 |
steve | Update | IOO | PMC locked |
I locked the PMC and the MC followed instantly. |
6656
|
Tue May 22 08:03:01 2012 |
steve | Update | SUS | ETMY oplev gets new laser |
Quote: |
The typical sign of a dying gas laser is that it glows for a few minutes only. The power supplies are fine.
Two new JDS - Uniphase 1103P lasers ( NT64-104 ) arriving on Monday, May 21
|
Yesterday I swapped in new He/Ne laser with output power 3.5 mW The return spot on qpd is large ~6mm in diameter and 20,500 counts
The spot size reduction require similar layout as ETMX oplev. |
6665
|
Wed May 23 10:40:21 2012 |
steve | Update | IOO | PMC locked |
Quote: |
I locked the PMC and the MC followed instantly.
|
|
6666
|
Wed May 23 11:30:39 2012 |
steve | Update | PEM | new emergency back up lights installed |
New self checking emergency back up lights were installed at 13 locations in the 40m lab. |
6672
|
Thu May 24 10:10:04 2012 |
steve | Update | IOO | PMC locked |
The PMC behavior is not changed.
|
6678
|
Thu May 24 16:39:47 2012 |
steve | Update | General | steve's webpage example |
3 strip charts monitoring on 24 hours time scale: Vac, PSL-IFO, SUS and 10 channel video monitoring inside - outside of 40m lab |
6700
|
Tue May 29 10:08:21 2012 |
steve | Update | IOO | centered IOO monitoring qpds |
IOO Angle & IOO Position QPDs centered. |