For the 35W beam.
Found BOTH cds file servers in read-only bad states this morning. Powered off and disconnected power from cdsfs0 and cdsfs1, then powered back up. This is the only way we've found to reliably reset the RAID controller on these computers.
Here are the crash times:
| cdsfs0 | 09:42 |
| cdsfs1 | 00:03 |
It appears that cdsfs1 crashed while rsync'ing cdsfs0 (cron job runs at midnight), and that cdsfs0's crash was coincidental.
I attach photos showing the serial number side of the ITMY elliptical baffle and the ITMX elliptical baffle, respectively, with the beam splitter in the background to document their orientation.
As a result of the power increment [1] we now have 4.76 mW of the infrared light at the field rack, which used to be 2.4 mW in the morning [2]. Yeah.
- - - - Measured Beam Powers
Incident on the refcav 21.4 mW
Incident on the fiber = 8.91 mW
The fiber power at the field rack = 4.76 mW
[1] LHO alog 6017 "Power into reference cavity increased"
[2] LHO alog 6103 "Coupling into ALS fiber on PSL table"
Gerardo, Gerardo Jr., Symon, Keita, Sheila, Kiwamu
We moved ISCT1 closer to HAM1 at its west side, installed a beam duct and confirmed that the PSL sample beam nicely goes through the viewport to ISCT1.
We are ready to align the optics on ISCT1 for the doubling test to generate the green light.
ISCT1 shift:
The ISCT1 enclosure which had been put afar from the HAM1 chamber was rolled closer to HAM1. Before moving it the clean room was also rolled toward south to accommodate ISCT1 as the clean room was too close to let ISCT1 go in. At the moment the distance between HAM1 and ISCT1 is that one person can just get through between the HEPIs and the enclosure. Also, as a part of the preparation of the laser barriers we put two black metal panels at the north side of the enclosure. The panels were wiped before they got in the clean room.
Beam spot position check :
Then we transitioned the LVEA to laser hazard for checking the spot position at the lower right viewport and the enclosure hole. At the HAM1 viewport the beam was at almost the center of the guillotine guard (as we aligned the in-vac mirror the other day) and slightly off in mainly the horizontal direction by 1 cm toward north, which is small enough comparing with the viewport diameter. At the enclosure hole it was off from the center by 4-ish cm toward south and by 4-ish cm higher. This is fine as the hole diameter is 10". We are satisfied with this alignment and hence there is no need to steer the beam with the in-vac steering mirror. At the moment the beam doesn't hit the upper periscope mirror in the ISCT1 enclosure but the beam height looks already perfect. So we just need to translate the periscope by ~ 4 cm to catch the beam, which is within our expectation.
Installation of duct:
We installed a beam duct and it now connects the viewport and the enclosure hole. This is exactly the same duct style as that we installed for IOT2L. The yellow cover of the viewport was removed and put right under the HAM1 door. We didn't remove the guillotine because we didn't find the dust cover which is supposed to cover the guillotine slit when it is absent. Although we found one dust cover in the stash nearby HAM3, this looked too big. So we left the guillotine in.
ISCT1 HEPA
We wiped the interior of the table before the enclosure was moved. We let the HEPA of ISCT1 run at its lowest speed to avoid sending dusts from the inside of the enclosure. Since the enclosure is almost entirely in the clean room probably it may not need to have the HEPA running. If people think it is doing nothing but blowing up dusts we can shut the HEPA off.
Attached are plots of dust counts requested from 5 PM April 9 to 5 PM April 10. Odd drop off in counts in the beer garden (LVEA 5) at around 1 AM.
Figure 1 shows beam spot views associated with the BS. I use these to look for potential scattering problems; the camera and flash is placed very close to the center of the optic where the beam spot will be. The flash mimics the scattering of interferometer light from the beam spot and lights up regions that will retroreflect interferometer light back to the beam spot, where it can recombine with the main beam to produce scattering noise. Of course the technique is limited by different angular distributions of scattered IFO light and light from the flash, as well as by color differences, but it gives a rough idea. I worry a bit about how bright the ITMY cage is, as viewed from the BS beam spot.
Kyle and I left a GNB bellows inside one of the small cleanrooms in the LVEA, located by the North wall of the East bay. Please do not remove from under cleanroom, if this item is on the way please let us know.
I updated the h1cds alarm handler files to include the front ends which have been added recently. The alh config files alarm on CPU MAX for IOP and user models, and STATE_WORD for the IOP model. Not all iop safe.snaps have been completed to set the STATE_WORD alarms.
I also updated the h1alarmmanager.db EPICS database for the alarm manager system, and its associated MEDM screen (see attached image).
GregG, JimW
After IAS gave a thumbs up on the BSC2 alignment, Greg and I started attaching the vertical HEPI actuators. With relatively few hiccups, all four actuators were attached. Shifts were relatively small at the dial indicators (all less than .003"), but we'll confer with IAS to make sure we haven't screwed up too bad. Horizontal actuators are up next, should be able to finish by this time tomorrow.
08:00 Dust monitor alarm in EY and EX. Crane cleaning in EY and Apollo working in EX LASER Hazard 09:08 Transition to Laser Safe – Michael R 09:40 DOE start seismic testing in 300 Area near station H3A Dave B updating alarm handler Betsy, Travis, Margo, Kate, and Hugo working in and around HAM 3, HAM2, and BSC2 13:08 DOE stop seismic testing Michael R working with Apollo cleaning in the PSL Enclosure Sheila & Keita move ISCT1 into HAM 2 cleanroom and setup laser safety barriers Filiberto C & Erin pulling in rack cables for BSC3 Filiberto C & Ben A pulling in rack cables at EX for BSC9
Kiwamu, Michael R
We increased the power going into the ref cav to get more light into the ALS fiber pick off. We now have about 23 mW going in. We ran a transfer function and found a lot of noise around 380 kHz, very close to the UGF. To get rid of this we decreased the common gain to 2 dB, giving a gain margin of 2dB. The UGF is now at 200 kHz.
Additionally, the PD in transmission of the ref cav was saturating, so I put an ND 0.3 filter infront of it. This was the lowest one I could find, and it is now reading ~ 3V.
I found the FSS couldn't recover from an oscillation event and had to decrease the fast gain to 6 dB for it to get back.
Kate G, Margot P, Travis S, Betsy W
MC2 has had its blade tip EQ stops replaced with the new shorter version. HAM2 and 3 have been fully photographed for contamination control efforts. Spray cones for both the HSTS and HLTS were assembled after some minor modifications were made on the fly. MC2 has had its first spray on First Contact layers applied. This required moving the baffle in front of the suspension in order to get the spray cone in place and to make room for a hand and spray bottle. Its position was marked with extra dog clamps and will be returned upon completion of cleaning. This work will continue tomorrow with First Contact being sprayed onto the remaining MC and PR suspensions in both chambers. Additionally, the BS has had its IAS thin-coated First Contact reinforced for its upcoming removal necessitated by baffle alignment.
Betsy writing: Note, we are only FC cleaning the 3 MC-HR surfaces, and the PRM-HR surface, as per COC instruction.
HAM3-ISI was rebalanced this morning. CPS readouts are attached.
SUS still have teflon shims to remove (white, on attached picture). Those are set between the earthquake stops and the optics, as a protection for the glass. We tried to account for them while balancing. CPS readouts are given with those shims on.
Kiwamu, Sheila This morning Kiwamu and I went into the PSL to see if we could improve the coupling of the reference cavity transmission into the ALS fiber. There were 4.72mW of light incident on the fiber coupler. We connected the two ends of the fiber at the field rack to each other so that the light was returning to the PSL with some extra losses due to the extra coupler, and saw 1.46mW coming out of the fiber. We moved the lens closer to the fiber coupler closer to the fiber coupler by about 1 cm total, and saw the power on our power meter inside the PSL increase to 2.1 mW. We noticed that as we moved the lens the alignment changes not only in yaw but also in pitch, meaning that the beam is not centered vertically on the lens. We can probably improve the coupling more by adjusting the lens positions more, but this will be easier to do if we have a beam leveler and make sure the beam is really level before we start. When we left Kiwamu measured the power coming out of the fiber at the rack, which was 2.4mW, so now the coupling efficiency is 51%. Better than 37% measured yesterday but there is still room to improve.
Travis and I checked the orientations of the 8 UIM permanent magnets, in-situ inside BSC1, and found them to be correct.
Attached are plots of dust counts requested from 5 PM April 8 to 5 PM April 9. There seems to be a large spike in > .3 micron counts at end Y from ~ 2 AM - 3 AM, and a smaller corresponding spike at end X.
The times appear to be wrong towards the ends of these plots. There should be a gap in the data due to a DAQ restart. This can be seen from the fact that the number of minutes does not go to 1440. This was realized in comparing these plots to those produced by dataviewer.
