Below the list of the activities communicated in control room:
TCS: det hartman sensor re-installation (#69673);
TCS: NI alignment check with hartman det sensor, in progress...
Air Conditioning
from 9:50UTC to 10:20UTC I set the detection area air conditioning system in "Portata Nominale" to allow the work on det hartman sensonr;
In order to start the check the NI HWS alignment with the NI RH of this afternoon, we put back the HWS-DET camera in place of the CCD.
The same plot related to 2 events that occurred on 2026-08-20-04h58m40-UTC and on 2026-08-20-08h51m30-UTC :
As already experimented 2 times during the week from 17-22 August, the SDB2_DBOX_LeftUp DBox was found unreachable in the Tolm network since 2026-08-30-14h22m05
Its have been recovered by performing
The problem is not understood. For the time being
The attached plot shows the trend of the DBOXes' timing error channels and their 12V power supply channels before the event, during the event, and after the DBoxes reconfiguration
DET_MAIN was stuck in UNKNOWN state because of a large offset on B1 PD3. After adjusting the offset around 19:45 UTC, I could put back DET_MAIN into the SHUTTER_CLOSED state. And then lock the arms using ITF_LOCK. SDB2 is not used for locked arms, so it should be ok to keep the arms locked even if SDB2 is not controlled.
The same plot related to 2 events that occurred on 2026-08-20-04h58m40-UTC and on 2026-08-20-08h51m30-UTC :
DET_MAIN was stuck in UNKNOWN state because of a large offset on B1 PD3. After adjusting the offset around 19:45 UTC, I could put back DET_MAIN into the SHUTTER_CLOSED state. And then lock the arms using ITF_LOCK. SDB2 is not used for locked arms, so it should be ok to keep the arms locked even if SDB2 is not controlled.
ITF found in DOWN State and COMMISSIONING Mode.
All times are UTC.
05:12 - 09:00 DAQ: EPRB, SIB2, ALS DAC firmware update (Masserot, #69668).
09:26 - 10:38 PSTAB 50Hz harmanics feed-forward preparation, turned on at 10:18, and it will be turned of at the end of the day (Was, #69666).
10:37 CITF relocked only at 1F stage, the handoff to LOCKED_ARMS_BEAT_DRMI_3F caused several unlocks.
ITF left in COMMISSIONING Mode and LOCKED_ARMS_IR State.
We continued to deploy the DAC1955 v3r3 firmware on the DAC1955 boards by completing the SPRB part and running it on the SIB2 and ALS subsystems.
Operations performed between 2026-08-28-05h30m03-UTC and 2026-08-28-09h12m26-UTC
Below the detailled list of the DAC1955 boards updated and the related ACL's server
SPRB :
SIB2:
ALS
After the issue with the EIB actuators of August 14th and the several interventions to mitigate the problem, the green beam on the EIB got a bit misaligned, especially on the North arm path (Fig. 1). As a consequence, the yesterday attempt to lock the arms on the beating did fail.
In the afternoon of yesterday, we used the picomotors on EIB to realign both path (fig2). For the time being, we didn't realign the ALS_CEB_BPC, as we want to perform it with the CEB_GREEN off (to mainly align on the ARM signals), but for the moment is not possible to use the flip mirror without unlocking INJ.
To be noted that at first attempt, the picomotor were not responding, even with a restart of the server. We needed to physically unplug and replug their power supply in the IER to get them working. Being the second time in few weeks that this happens, we will investigate wheter it is due to an hardware problem.
This morning I have corrected the logic error at 10:16 UTC.
Figure 1. Shows the safety working properly, the FF corrections visible in INJ_PSTAB_NOISE and the FF tracking loop start at 10:17:30 UTC, 20 seconds after the RFC locks, despite the ENABLE flag being activated since at least 10:17 UTC.
Enabled also the 250Hz FF, and leaving it on for the day to see if any issues arises over several hours. I will disable the PSTAB FF loop at the end of the day as a precaution for the weekend.
In addition to the two action reported, the "energy safe" option has been selected yesterday too (see fig. 1).
Other than the usual 1Hz comb noise, present with those chiller when the safe mode is not selected, we could see a sawtooth oscillation on T of the chiller and the neoVAN diodes, with a period of about 11min (see fig. 2).
The oscillation went away as soon as we changed the operation mode.
Yesterday evening I have tried to add a safety to the feed-forward to automatically turn it off when RFC_TRA_DC goes below 2V (unlocks).
Figure 1 shows the result just after restarting the ISYSnoise process with the changes. The FF correction (eventually dominating the RMS of INJ_PSTAB_NOISE) starts immediately with a ramp of 20 seconds, instead of starting with a delay of 20 seconds after the RFC locks. I need to correct the logic of the safety.
---------
16:40 UTC restarted ISYSnoise to add a check that disables the 50Hz
harmonic FF when the RFC is not locked. Not fully certain if it works
as the timer is 20s while the 50Hz FF loop started acting only 10s
after the RFC locked.
17:01 UTC (5min) 250Hz FF enabled and stable
17:16 UTC disabling 50Hz and 250Hz FF
ITF found in COMMISSIONING Mode and DOWN state, with MISALIGNED_ALL_BUT_NI state on ARMS_LOCK node (equal to SINGLE_BOUNCE_NI state from ITF_LOCK).
Planned activities:
- First check on DET HWS and SLED beam (Lumaca, Corubolo), concluded at 11:10 UTC.
- Opening of Cryo Valves (VAC team), performed at 08:49 UTC.
- New position for GRAS microphone on Injection Tower, concluded at 09:15 UTC.
- Spare Neovan Chiller tuning in EERoom (Lagabbe, Zaza), performed at 12:00 UTC.
In order to allow the TCS activity:
- I set UTA DET in Portata Nominale.
- I recovered all metarton nodes in standard state.
- Thanks to Ruggi we realigned and relocked cavities.
- I recovered the SDB2 vertical position via stepping motors and close SDB2_SBE loop.
- Thanks to Gouaty we recovered the SDB2 position and close LC loops.
- I set ITF in SINGLE_BOUNCE_NI with SR manually aligned.
- Upon concluded the activity (11:10 UTC) I set again UTA DET in Portata Ridotta and re-misaligned SR.
I tried to move on with the lock acquisition up to ACQUIRE_DRMI in order to perform the usual cross-alignment, but unfortunately ITF unlocked at LOCKING_ARMS_BEATING while Engaging boost filter #1. Investigation in progress on EIB (Spinicelli).
ITF now in standard state in LOCKED_ARMS_IR.
This afternoon around 14h20 local, we increased the chiller temperature setpoint from 16 C to 17 C, and increased the water flow.
This morning between 08:30 and 09:15 UTC we moved the microphone from the west side of the INJ tower (nearby the EEroom, Fig1), see #69458.
We placed it on the terrace near to the Injection Tower on the west side close to the already present Netwonian microphone (Fig2).
The channel is is unchanged: ENV_CEB_LLR_MIC (#69466).
List of corrections deployed with this update:
For comparison, logbook entry 64819 contains an image of the HWS-DET SLED beam acquired with a CCD camera in July 2024. The beam observed today appeared qualitatively similar to the one shown in that entry.
Is attempted a measurement of sound transmission between the CEB hall and the labs INJ and DET. The white acoustic noise injection of July 28th is used.
The used reference microphones are:
The averaged ASD of the reference microphones are computed first (Figure ...), then converted into Sound Pressure Levels in 1/3rd Octave bins (Figures...), finallly the "transmission loss" (here called "isolation") between the hall and the two labs is computed as the difference of the SPL of the outside and the SPL of the inside mics (Figures ...). On the same figure is reported the transmission loss requirement of the actual clean rooms, from VIR-0357A-12. All units are acoustic dB:
Lout = np.where(Lout > LoutQ, Lout, np.nan)
Lin = np.where(Lin > LinQ, Lin, np.nan)
Liso = np.full_like(Lout, np.nan)
mask = Lout > Lin
Liso[mask] = Lout[mask]-Lin[mask]
Note that this evaluation is not complient with the ISO standards (UNI EN ISO 16283-1:2018) which would require multiple microphones properly located and as well as a proper source. Also, no correction is applied for the reverberation effect (as foreseen by ISO). Being the source (loudspeaker on DET terrace) is much closer to the DE then to the INJ lab, there is a obvious bias overestimating the INJ lab isolation, while underestimating the DET lab isolation. Also, inside microphones are placed under some cover (plexiglass for the LB, and metallic for the EDB) which cause an overestimation of isolation above some 100Hz, or 1kHz. However, despite these limitations, these measurements can be used as future reference, if the same source and microphones location is adopted.
Liso values are printed in the attached .txt files.
We entered the DET lab at approximately 8.00 UTC. For the duration of the activity, Nicola set the DET lab HVAC system to high-speed mode.
We first unplugged the power supply and all the cables of the link located behind the HWS. We then removed the HWS camera and installed the CCD camera in its place, restoring all the required connections (see Fig. 1).
Afterwards, we went to the Detection Electronic Equipment Room and physically switched on:
the HWS-DET power supply
the DET SLED power supply
We then attempted to connect to the CCD camera. The camera initially had to be reinitialised, after which the connection was successfully established. We set the SLED-DET voltage to 1.0 V and started to observe a signal on the camera.
Once Nicola confirmed that the required interferometer configuration had been established, the conditions were as follows:
suspended DET bench correctly positioned, thanks to Nicola and Romain;
SR, BS and NI aligned
WI, WE and NE misaligned
We increased the SLED-DET voltage to 1.2 V and observed the beam clearly on the CCD camera. When the DET flip mirror was closed, the beam disappeared from the camera, as expected (see Fig. 2).
The DET SLED beam appeared to reach the NI mirror correctly and return to the sensing camera without any significant clipping.
The following actions still need to be performed:
reinstall the DET HWS camera in place of the CCD camera
We left the DET SLED turned on at 1.2 V and the CCD camera ON.
For comparison, logbook entry 64819 contains an image of the HWS-DET SLED beam acquired with a CCD camera in July 2024. The beam observed today appeared qualitatively similar to the one shown in that entry.
In order to start the check the NI HWS alignment with the NI RH of this afternoon, we put back the HWS-DET camera in place of the CCD.
On Monday I forgot the restore the nominal position in TX of the SDB2 bench after the TX scan. This means that the bench was left by mistake in position TX = -420 urad for the past 3 days. I restored the nominal setpoint TX= -280 urad today at 09h03 utc.
Yesterday, 2026-08-27, the IRIG-B signal was disabled in the 100MHz-IRIG-B timing distribution to check the phase noise:
Looking at the LNFS and EOM 6MHz, 8MHz and 56MHz signals, I was surprised by the shape of their FFT's phase
According to these plots, the spare LNFS seems to be more noisy and with more lines
The chiller of the neovan electronics stopped working at around 14:00 utc. Probably due to normal device aging.
This afternoon we exchanged the chiller with the spare that was in the optics lab. The serial number of the old chiller is on the pictures attached to this post.
PS: In the chiller water tank, we found some 'sand' which is probably some metal oxide and particle coming from the electronic devices and tubing.
This afternoon around 14h20 local, we increased the chiller temperature setpoint from 16 C to 17 C, and increased the water flow.
In addition to the two action reported, the "energy safe" option has been selected yesterday too (see fig. 1).
Other than the usual 1Hz comb noise, present with those chiller when the safe mode is not selected, we could see a sawtooth oscillation on T of the chiller and the neoVAN diodes, with a period of about 11min (see fig. 2).
The oscillation went away as soon as we changed the operation mode.
Today we started the activity on the NI CO2 bench at approximately 8.00 UTC. Continuing to following the steps described in issue #186, we performed the NI outer ring checks:
We removed the mask from its nominal position and installed SPIRICON 2 in its place, using the post holder
We reduced the power in the DAS OUT branch to limit the power reaching the SPIRICON 2. We initially encountered an issue with the “TCSAgilisRot / Move NI_CO2_OUT” waveplate; to recover its operation, we stopped and restarted the TCSAgilisRot process from VPM
We checked the intensity distribution of the outer ring
We observed mainly a horizontal asymmetry, together with a very small vertical one. We therefore adjusted M10 to obtain a more uniform intensity distribution. Figure 1 shows the outer ring profiles before and after the adjustment.
After completing the adjustment, and before reinstalling the mask, we acquired an image of both NI DAS rings (Figure 2) with SPIRICON 2. The two rings appeared correctly aligned.
We then:
Removed the SPIRICON 2 from mask position and we put back the mask
Performed a quick check with SPIRICON 1 at the CINOGY position to verify that the mask correctly covered the hot spot.
Having completed the power distribution checks, we removed both SPIRICON cameras from the bench and proceeded with the on-bench alignment checks.
Using the Thermal Camera acquisition system, we observed the actuators and checked the relative alignment (DAS rings and CH). We found a small relative centering offset between the inner and the outer rings, along the vertical direction, which was corrected by applying a very small adjustment to the recombiner. Figure 3 shows the final alignment between the DAS OUT halo and the DAS IN ring; the DAS OUT halo was used because it provides a clearer reference for evaluating the centering.
After daily meeting, we also checked the alignment of the CH with respect to the DAS rings. No adjustment was required. Figure 4 shows the final alignment between the DAS OUT halo and the CH; again, the halo was used as the clearer centering reference.
After completing the checks, all flip mirrors were restored to their standard positions: the DAS IN, DAS OUT, and CH flip mirrors were closed to block the beams on the bench, while the CINOGY and Thermal Camera flip mirrors were left open to allow the beam to propagate towards the interferometer if required. The NI bench enclosure was then closed.
The activity on the NI bench ended at approximately 14:30 UTC.
The power-distribution and alignment checks on the NI CO2 bench can therefore be considered complete.
ITF found in COMMISSIONING Mode and DOWN state, with MISALIGNED_ALL_BUT_NI state on ARMS_LOCK node (equal to SINGLE_BOUNCE_NI state from ITF_LOCK)
- planned activity:
- CO2 bench checks (Lumaca, Corubolo). Still in progress...
ISYS
16:04 UTC - Neovan chiller switched OFF for unknown reason. Afetr a check, Gosselin discovered a problem on it. He is going to replace it with a spare one.
SBE
SPRB vertical position recovered via stepping motors.
