Displaying reports 78501-78520 of 83105.Go to page Start 3922 3923 3924 3925 3926 3927 3928 3929 3930 End
Reports until 11:51, Monday 19 November 2012
H1 SUS
jeffrey.kissel@LIGO.ORG - posted 11:51, Monday 19 November 2012 - last comment - 15:04, Tuesday 20 November 2012(4730)
H1 SUS ETMY Infrastructure Completion
I have filled out H1 SUS ETMY's new infrastructure, including
(1) Filling in the ISI to SUS WIT and SUS to ISI OFFLOAD paths, installed as was described for H1 SUS PR2 in LHO aLOG 4553. Nothing new -- same exact filters -- just using the H2 SUS ETMY (yes, H2 -- the SUS hasn't moved yet) matrices from
/opt/rtcds/userapps/release/isc/common/projections/ISI2SUS_projection_file.mat

(2) Installing the OPTICALIGN alignment offset calibration gain, as described in LHO aLOG 4563. Here, for this and all QUADs, the gain is

OPTICALIGN GAIN [cts/urad] = ( DAC [V/ct] * Coil Driver [A/V] * Coil/Magnet [N/A] * HSTS M1 to M3 [rad/N.m] * 1e9 [nrad/rad] )^-1
                           = ( (20/2^18)  * 0.009943          * 1.694             * 0.033514 (for Pitch)    * 1e9            )^-1
                           = 0.023219 [cts/nrad] for Pitch

                           = ( (20/2^18)  * 0.009943          * 1.694             * 0.015055 (for Pitch)    * 1e9            )^-1
                           = 0.051689 [cts/nrad] for Yaw

Note that I've gone with nanoradians instead of microradians (as was done for PR2), because the alignment offsets needed to align (at least the H2OAT) were already quite large (~75% of the M0 BOSEM range), so calibrating this gain into microradians (or any gain larger than 1, really) would have saturated the DAC. This provides for annoying large EPICS values, (retaining the -3027 and +5405 [ct] offsets needed for the H2OAT, means that these offsets are 58562 and 232783 [nrad]), but I think we can deal. I still need to adjust the OPTICALIGN screen to account for this difference (make the sliders have bigger default range and step size, as well as changing the legend to match).

(3) With further quantitative assessment pending, I've installed Rana's 2k to 16k anti-imaging filter in the 

L3_ISCINF_P
L3_ISCINF_Y

filter banks, in order to filter any imaging noise that arises from the inter-process-communication between the ASC model (running at 2k) and the SUS model (running at 16k). I attach a bode plot of the filter as installed (again, identical to Rana's).
Non-image files attached to this report
Comments related to this report
jeffrey.kissel@LIGO.ORG - 11:56, Monday 19 November 2012 (4731)
As of this entry, I've updated and committed H1 SUS ETMY's safe.snap here,
${userapps}/sus/h1/burtfiles/etmy/h1susetmy_safe.snap

as well as saved and committed the updated foton filter here,
${userapps}/sus/h1/filterfiles/H1SUSETMY.txt.

For both, I've checked that they're obeying the new schema, in which 
/opt/rtcds/lho/h1/target/h1susetmy/h1susetmyepics/burt/safe.snap
and
/opt/rtcds/lho/h1/chans/H1SUSETMY.txt
are soft links to the above userapps locations.
jeffrey.kissel@LIGO.ORG - 14:30, Tuesday 20 November 2012 (4746)
S. Aston, J. Kissel

Stuart was double checking my work (hooray!) and found several problems with my implementations of the OPTICALIGN offsets and gains.

(1) There's a typo in the labelling of the calculation (I wrote "for Pitch" twice, when one should be Yaw). The corrected statement is 

"For this and all QUADs, the gain is

OPTICALIGN GAIN [cts/urad] = ( DAC [V/ct] * Coil Driver [A/V] * Coil/Magnet [N/A] * HSTS M1 to M3 [rad/N.m] * 1e9 [nrad/rad] )^-1
                           = ( (20/2^18)  * 0.009943          * 1.694             * 0.033514 (for Pitch)    * 1e9            )^-1
                           = 0.023219 [cts/nrad] for Pitch

                           = ( (20/2^18)  * 0.009943          * 1.694             * 0.015055 (for Yaw)      * 1e9            )^-1
                           = 0.051689 [cts/nrad] for Yaw


(2) In my haste, I'd installed these gains exactly backwards (0.023 for YAW and 0.052 for Pitch). In fact, even further, I had calculated the offsets to-be-restored with the gains exactly flipped as well. Whoops! I've now corrected the gains, and changed the stored offsets to

Pitch: -3027 [ct] / 0.023219 [cts/nrad] => -132302 [nrad]  
Yaw:   +5405 [ct] / 0.051689 [cts/nrad] =>  104548 [nrad]


I'm Currently taking measurements, but I'll take a new safe.snap once I'm finished.
jeffrey.kissel@LIGO.ORG - 15:04, Tuesday 20 November 2012 (4748)
New safe.snap has been captured and committed to the userapps repo, as of version 3401:
/opt/rtcds/userapps/release/sus/h1/burtfiles/etmy/h1susetmy_safe.snap 
H1 CDS
david.barker@LIGO.ORG - posted 11:30, Monday 19 November 2012 (4729)
Remote 2fa login and ligo.org internal login working again

We had a kernel crash of the internal cds servers cdsldap0 and cdslog this weekend. Both computers are in the H2EE room, but only these two crashed.

The loss of cdsldap0 meant that remote 2FA log into CDS was not working. Neither was using your ligo.org account on the internal CDS workstations.

I restarted the servers and all looks good so far. Both machines had been running for 342days, so they needed file system checks.

H1 SEI
dale.ingram@LIGO.ORG - posted 11:13, Monday 19 November 2012 (4727)
BSC 1 Cartridge Installation, 11/15/12
Check ResourceSpace for the photo collection of last week's cartridge move.  This is the one-arm test cartridge that came out of BSC 8 early in October 2012.  Once on the test stand in October, the ISI's folding mirror suspension was transferred to the neighboring BSC 2 ISI and re-christened as the beam splitter suspension while the quad's position was adjusted on the BSC 1 ISI.  SUS locking photos courtesy of Jeff Bartlett.
Images attached to this report
H1 SUS
jeffrey.kissel@LIGO.ORG - posted 11:12, Monday 19 November 2012 - last comment - 12:02, Monday 19 November 2012(4728)
Taking H1 SUS ETMY Transfer Frunctions
Gathering closed loop transfer functions on H1 SUSITMY, started ~1:30p ET / 10:30a PT, will cease (regardless) at 3:00p ET / 12:00p PT.
Comments related to this report
jeffrey.kissel@LIGO.ORG - 12:02, Monday 19 November 2012 (4732)
Transfer functions complete.
H1 General
kiwamu.izumi@LIGO.ORG - posted 09:34, Monday 19 November 2012 - last comment - 15:16, Monday 19 November 2012(4726)
A bad RF cable in the C4 remote rack

[Dick / Kiwamu]

 We found an RF cable whose signal level depends on the angle of one of the cable end. This is not good. I consulted with Filiberto on this issue and we decided to leave it to the electricians who are coming in the next week from Caltech. Or if the cable turns out to be necessary soon, we can just swap or fix it by ourselves.

--- the Cable
place: remote rack C4
connection between : U42-1 and U9-1
description:71 MHz for a VCO
length: ~ 2 m
type: N male / N male

--- Symptoms
 * The RF power dropped from 11 dBm to -8 dBm suddenly while doing nothing
 * Applying tension at the cable end (the U9-1 side) introduces variation in the RF power by ~15 db or so.

--- Assessment
 At the beginning we thought that the power variation was due to the connector which is a part of the U9 circuit box (i.e. the channel 1 output of an RF distribution amplifier D100024/S1000595). We pulled out the circuit box and brought it to the EE shop to do a further investigation. We didn't find anything wrong. So we put the box back to the rack and it seems working fine.
 Eventually we located the issue and confirmed that it was in the RF cable and not in the box. Currently everything is back to place.

Comments related to this report
kiwamu.izumi@LIGO.ORG - 15:16, Monday 19 November 2012 (4735)

I have just removed the cable and cut it so that noboday can accidentally use it.

H1 PSL
michael.rodruck@LIGO.ORG - posted 09:20, Monday 19 November 2012 (4725)
PSL plots

For the 35W beam

Images attached to this report
Non-image files attached to this report
H1 General
robert.schofield@LIGO.ORG - posted 19:18, Friday 16 November 2012 (4724)
Mitigation of ~9 Hz chilled water turbulence peak in EY seismic level

The 59 Hz chiller pumps at EY produce turbulence in the water lines that results in a peak at about 9 Hz in seismic spectra at Y-end. This peak creates problems e.g. for ISI. We have been planning to install a variable frequency drive (VFD) at EY so that we could reduce the water flow, in hopes of reducing the turbulence. The VFD was installed at EY this week and I ran some tests at various frequencies (pump speeds). Figure 1 shows that the peak is nearly at background with the VFD set to 30 Hz, instead of the nominal 60 Hz. 40 Hz is also pretty good so we decided to run at 35 Hz from now on. We believe that the cold water flow rate is down by less than a factor of 2 and that this should be sufficient for our needs. We will find out for sure when it gets hot next summer. We also now have VFD at EX and the corner station so we can adjust these as needed.

End Y is, as of now, in a seismic condition pretty similar to what we plan for aLIGO science mode. There are still a few pumps making sharp lines, but the broad band should be pretty close, especially when people are not out at End Y. To test the pointing of the seismic array, I placed a shaker on the floor at two locations Wed. night, running at 12 Hz. The times were:

Nov. 15 2012 0:54:54 UTC to 2:20:40 UTC (last ten minutes were the most quiet) and

Nov. 15 2012 2:29:40 UTC to 3:00:00 UTC (first fifteen minutes were the most quiet).

Robert S., Richard M., John W.

Non-image files attached to this report
LHO General
patrick.thomas@LIGO.ORG - posted 19:15, Friday 16 November 2012 (4723)
plots of dust counts
Attached are plots of dust counts > .3 microns and > .5 microns in particles per cubic foot from approximately 6 PM Nov. 15 to 6 PM Nov. 16. Also attached are plots of the modes to show when they were running/acquiring data.

There is still an occasional calibrate failure alarm on the dust monitor in the OSB optics lab.

Dust monitor 4 in the LVEA was turned back on.
Non-image files attached to this report
H1 ISC
alberto.stochino@LIGO.ORG - posted 18:11, Friday 16 November 2012 - last comment - 18:33, Friday 16 November 2012(4721)
PSL reference cavity transmission picked-off and launched into ALS fiber

[Michael Rodruck, Alberto]

Today we finished setting up the optical path to couple the PSL reference cavity tranmsitted beam into the ALS fiber. After we mode matched the beam to the fiber launcher, we aligned it into the fiber by using the OzOptics auxiliary fiber laser.  We coupled 3.0mW into the fiber, out of the 5mW coming from the reference cavity: a 60% matching. It didn't look like this could be imrpoved by much.

Both ALS setups on the PSL table are now almost complete. The only work left to complete is the replacement of the Faraday's mount on the ISCT1 pick-off path: the mount is currently under construction at the machien shop.

Images attached to this report
Comments related to this report
alberto.stochino@LIGO.ORG - 18:33, Friday 16 November 2012 (4722)

Details on the optical alyotu of the fiber setup are in LIGO-T1200471-v7.

H1 PSL
robert.schofield@LIGO.ORG - posted 17:47, Friday 16 November 2012 (4719)
Hose quick-connects are noisy: PSL crystal chiller vibration investigation

One hypothesis for the source of excess vibration noise on the PSL table from the crystal chiller circuit (here) is that the ~2 mm aperture in the quick-connect hose fittings on the 5/8” ID hoses causes a turbulent jet of water that, especially if bubbles are present, modulates the flow of water. Figure 1, lower plot, shows that a quick-connect is about two orders of magnitude more noisy than a barbed barrel connector for the 10 - 15 l/m flow through the crystal circuit of the crystal chiller. Figure 2 has a photograph of the setup.

To see if the noise from the quick connect might be loud enough to explain the noise from the whole circuit, we clamped the quick connect setup used for the above measurement to the outside manifold of the crystal box (setup photo shown in Figure 2). The upper plot in Figure 1 compares the nominal noise to the noise from this setup. The peaks produced in this way are relatively large but don’t match the peak from nominal flow through the box. However, the momentum transfer to the table for our test is much different than in the actual setup.

I think the results are suggestive enough that it would be worth an experiment where we replace the two quick connects at the crystal box manifold with barbed connectors. To further improve the flow, we suggest that we use the capped threaded holes for this in order to make one less 90 degree turn. Figure 2 also has a photograph illustrating the proposed modification.

Robert S., Michael R., Rick S.

Non-image files attached to this report
H1 CDS
david.barker@LIGO.ORG - posted 17:27, Friday 16 November 2012 (4720)
Added BSC6 Ion Pump EPICS channels to Vacuum Controls

WP#3568

Following the wiring of the new BSC6 75l/s Ion Pump, I created a new database file for the h0veey VME IOC called HVE-EY:75IPBSC6.db. This is essentially a copy of the existing BSC10 database, with BSC10 replaced by BSC6 and 411 replace with 425.

At 13:31 we restarted h0veey with the new database, all went well. I also changed:

I also fixed the MEDM to MEDM links for the vacuum screens on the control room machines.

LHO General
patrick.thomas@LIGO.ORG - posted 17:03, Friday 16 November 2012 (4717)
Ops Summary
Unifirst arrived with floor mats.
A viewport was installed in the septum between HAM 1 and 2.
Michael R. transitioned the LVEA to laser hazard for MC locking work.
Michael R. transitioned the LVEA to laser safe.
Richard and Dave added the ion pump on BSC6 to the control system.
Michael R. and Alberto worked on aligning the PSL ALS optics.
Dale lead a tour through the control room.
H1 SUS
jeffrey.bartlett@LIGO.ORG - posted 15:47, Friday 16 November 2012 (4718)
Move PR3 & PRM to Optics Table
   This afternoon Andres and I removed the H1-Pr3 and H1-PRM HAM suspensions from their storage containers and placed them on the chamber-side optics table in the LVEA. No problems were encountered during the move.  
H2 SEI
hugh.radkins@LIGO.ORG - posted 12:07, Friday 16 November 2012 (4716)
WBSC6 HEPI Dial Indicator Disabled-Partly
I needed a little hardware for the dial indicators for BSC1 and I had to rob from BSC6.  The two western DI trees are no longer engaged but the East side has three axis monitoring still on both corners.  And of course there are still the HEPI IPS.
Before disconnecting the west side, I recorded the indicators and comparing to my last recordings, they are still reading valid.  I see a coherent rotation of about 0.1mrad clockwise wrt the readings I logged on 30 Aug.  The vertical readings are unchanged.
H1 CDS
james.batch@LIGO.ORG - posted 12:05, Friday 16 November 2012 (4715)
Changed default nds server to 0
For new shells started after 12:03 PST, the default nds server has been changed to h1nds0.

H1 AOS
douglas.daniel@LIGO.ORG - posted 11:35, Friday 16 November 2012 (4714)
Last viewport installed for IO Septum - between HAM1 and HAM2
Installation of last Custom Wedged Viewport VP2 to IO Septum (between HAM 1 & 2) completed with Apollo.
Wedged VP orientation was with the thick part of wedge (scribe mark on flange) to 3:00 O,clock position so deflection is horizontal in nature.
HAM1 can now be isolated as needed.
Images attached to this report
H1 IOO
cheryl.vorvick@LIGO.ORG - posted 18:37, Thursday 15 November 2012 (4713)
IO alignment of IR beam through HAM2 and into HAM3 - success! HAM3 back to HAM2 - no so much.
The IR beam was successfully aligned from the PSL to HAM2, through the IO periscope, off 2 steering mirrors, and through MC1 to HAM3.  In HAM3, we discovered that MC2 has FC, which precludes bouncing a beam back to HAM2.  We aligned the beam to MC2, explored some options for continuing to work, and then called it for tonight.
Displaying reports 78501-78520 of 83105.Go to page Start 3922 3923 3924 3925 3926 3927 3928 3929 3930 End