Updating the SBE server configurations for the DAC1955 V3 firmware, we fpund strange Tolm packet setting for some Acl*s servers running of the SQB1 rtpc, more precisely for

• the SQB1_LC server where the  TOLM packets for the "SQB1_DAC_LC_LVDT_out_INT" and "SQB1_DAC_PSD" DAC1955  was not sent at the correct frequency
  • TOLM_OUTPUT_PACKET_SLICED    "SQB1_DAC_LC_LVDT_out_INT"    50000    DAC1955_FREQ  with    DAC1955_FREQ (= 100000)
  • instead of TOLM_OUTPUT_PACKET_SLICED    "SQB1_DAC_LC_LVDT_out_INT"    10000    DAC1955_FREQ  meaning that only 2 over the 10 packets were sent 
  • same thing for  TOLM_OUTPUT_PACKET_SLICED    "SQB1_DAC_PSD" 50000     DAC1955_FREQ 

We set the correct parameters but when we restarted the SQB1_LC server, we lost all the input Tolm packets . To recover the Tolm input packets, a reboot of the SQB1_rtpc was required .

We made several trials and at the end we set

• for the SQB1_LC server; 
  • this line for the  SQB1_DAC_LC_LVDT_out_INT Tolm packet in order to have all the DAC sample: TOLM_OUTPUT_PACKET_SLICED    "SQB1_DAC_LC_LVDT_out_INT"    LC_LOOP_FREQ    DAC1955_FREQ
  • this line for  the SQB1_DAC_PSD Tolm packet as the DAC channels are only constante value : TOLM_OUTPUT_PACKET_SLICED    "SQB1_DAC_PSD" 50000     DAC1955_FREQ as previously
• for the SQB1_FI server,  as we would like to have output Tolm data flow and it s only temperature control loops
  • this line for the SQB1_DAC_01_INT Tolm packet : TOLM_OUTPUT_PACKET_SLICED    "SQB1_DAC_01_INT"    50000    DAC1955_FREQ   instead of  TOLM_OUTPUT_PACKET_SLICED    "SQB1_DAC_01_INT"    LOOP_FREQ(10000)    DAC1955_FREQ previously

With these configurations,

• all the servers are correctly running
• the output Tolm data flow is the same as before the modifications, meaning that the use of DAC1955 v3 firmware will be helpful 
• the SBE and LC loops were successfully closed 

Operations performed between 2026-05-07-13h45m08-UTC  and  2026-05-07-14h47m25-UTC

• This morning, before starting to work on the BPL loop, we unblocked the beam transmitted from the PMC and we took the references of its position on the BPL QPDs (see fig 1).
• Then we plugged the PZT to the DAC in Eeroom. The PZT driver accepts -2V +12V, while the DAC dynamics is +-10V but due to the LEMO 3 PIN - BNC adaptation it is restricted to +-5V. On the PZT driver the DAC input is summed with a offset (from 0 to 10 V) that can be manually adjusted, and then amplified by slightly more than a factor 10, to -30 +130 V.  We manually set the offset to mid range (5V), so that we can correct around this value with the DAC.

lines 127-130 in  /virgoData/VirgoOnline/ISYS_EER_dac.cfg

ACL_DAC_CH    dac1955_EER_DAC2_ch03    1    DAC1955_FREQ    BPL_PZT_EIB_M1BH_CORR            0            1            "None"                        "ad1955-10v"    ""
ACL_DAC_CH    dac1955_EER_DAC2_ch04    1    DAC1955_FREQ    BPL_PZT_EIB_M1BV_CORR               0            1            "None"                        "ad1955-10v"    ""
ACL_DAC_CH    dac1955_EER_DAC2_ch05    1    DAC1955_FREQ    BPL_PZT_LB_M14H_CORR            0            1            "None"                        "ad1955-10v"    ""
ACL_DAC_CH    dac1955_EER_DAC2_ch06    1    DAC1955_FREQ    BPL_PZT_LB_M14V_CORR            0            1            "None"                        "ad1955-10v"

• We injected a 2Hz line on the PZTs during 90s. Here the gps for each actuator

gps = [1462194492 1462194603 1462194722 1462194871]; actuators = {'INJ_BPL_PZT_EIB_M1BH_CORR','INJ_BPL_PZT_EIB_M1BV_CORR', 'INJ_BPL_PZT_LB_M14H_CORR', 'INJ_BPL_PZT_LB_M14V_CORR'};

• The sensors are: {'INJ_BPL_QF_h_norm', 'INJ_BPL_QF_v_norm','INJ_BPL_QN_h_norm', 'INJ_BPL_QN_v_norm' };
  • QF mainly see the tilt (done with EIB M1B and also a bit with LB M14)
  • QN mainly see the shift (done with LB M14)
• We computed the driving matrix with the attached script and closed the loop. We started to try different filters (see 2nd plot). As a final test we removed the resistences at the output of the PZT driver, from around 15:58 UTC to 16:20 UTC (but there is a lot of noise on the signals, introduced by the amplifier itself, so we put it back).

To do next:

• to perform noise injections and design a better filter which does not introduce noise on QF h between 20 and 100 Hz
• check availability for a DAC +-20V
• add in the ISYS_BPL code:
  • a latch to keep the setpoint when the loop is open 
  • clip on the corrections to avoid too large beam excursion
  • trigger to open the loop if there is no signal

Yesterday, additional inspections (already reported in 69077) of the PAM viewports were carried out using a thermal camera:

• NI: big viewport — visible coating delamination (see Fig. 1)
• WI: small viewport — no visible coating delamination (inspected only from the outside see Fig. 2)

At 07:50 UTC, all CO₂ lasers (CH and DAS) were switched off. Shortly thereafter, Cecilia deactivated the Guardian system and placed the chillers on standby.

Note: outputs disabled; power supplies left ON.

I went back and re-installed the ampifier I removed yesterday.

Data are back online (Fig.1), glitches still present.

Yesterday morning we made a test turning off the air conditioning unit in the laser lab, in order to check if we are still dominated by the acoustic noise. In order to do this, we lock the west arm using the green beam and we checked the fft of the error signal with the air conditioning ON (purple curve) and OFF (blue curve). Figure 1 shows also different monitorings in the Laser and EIB bench (microphone and accelerometer).

In the plot the spectrum barely changes between the two states, which means that we are no longer dominated by the ambient noise which was the main target of this action. This will allow us to increase the bandwidth of the CARM and DARM loops (which currently are around 5 Hz), increasing the robustness of the system.

We investigated the missing signals on WI MIR local controls.

Spinicelli noticed that the SLD switch was off and flipped it, turning the beam back on. We realized that the contact between the power cord and the switch box is very precarious and turning or touching the cord is enough to turn the laser off again. We carefully adjusted its position until it worked, but it is clearly a non ideal situation and we will need to replace either the cable or the box itself.

After turning the SLD back on, we noticed periodic glitches on WI_MIR_PSDF in the form of a ~1s long burst followed by two large glitches, spanning ~1 V peak to peak. This structure repeats every ~5 seconds (Fig.1).

We investigated this behavior by opening the local control box and swapping the cables between the amplifiers of the PSDF and PSDI photodiodes, both the power cables and the data cable connecting them to the photodiodes. The issue remained on PSDF, which led us to conclude that the amplifier itself was malfunctionig and we removed it to substitute its components.

Surprisingly though, the PSDF signal still shows the same glitches without the amplifier (Fig.2), meaning that the issue is likely downstream, possibly at the level of dsp electronics. We will contact Boschi to investigate.

The current situation is that the signal is disabled, with the amplifier uninstalled and currently sitting in the Roma 1 office in the office building. We will reinstall the amplifier and restore the previous situation tomorrow morning, as the components inside the optical levers box are clearly not at fault for this issue.

Critically, the PSDF signal serves as reference for the WI's alignment and it must be restored in some form before uninstalling the mirror.

During the operations I had to move a magnetic field sensor out of the way to access the optical levers box. I repositioned it as precisely as I could and informed Tringali and Fiori afterwards.

As a first step towards the commissioning of the BPL this afternoon we installed a mirror before the EOMs on EIB to send the main beam on a divergent lens (-30mm and then a beam dump), so that we will be safe while doing tests on the PZT (the risk would have been to burn something since the power density at the level of the EOMs is high).

We added 2 mirrors, 1 lens, 1 beam dump, and removed 1 iris, for a weight of about +1kg. We rebalanced the EIB and left it suspended. The PMC is scanning and the mirror at its output is flipped.

Tomorrow we will plug the PZT to the DACs and start the commissioning of the QPDs.

This morning, we upgraded the machine hosting both the database and the web component of the DMS service.

The procedure was carried out as follows:

1. The servers were stopped to prevent any further database writes.
2. The database was copied to the test environment, where the application code had already been verified and updated in preparation for the upgrade.
3. The old production machine was powered off, and the test machine was cloned and renamed using the original production hostname.
4. The new machine was moved to the same Pool as the previous production system.
5. The new machine was activated.
6. Both backend services and the web interface were verified to be fully operational.

New system configuration:

• Server: AlmaLinux 9
• Web Server: Apache 2.4 (php-fpm)
• PHP: 8.3.30
• Database: MariaDB 10.5.29
• phpMyAdmin: 5.2.3

The entire process took approximately 2.5 hours, from 09:00 LT to 11:30 LT, during which the DMS service was unavailable. Most of the time was spent copying the database, particularly the tables containing plot data.

The application code had been previously tested in the environment. No anomalies have been detected so far; however, the system will continue to be monitored over the coming days.

Two flip mirrors on the EIB ALS path, one to cut the IR seed and the other to remove only the green beam, are now installed and remotely controllable via VPM, on the TTL_inj server, under TCS section.

They are named respectevely ALS CEB IR and ALS CEB GREEN.  

During the opening of the NI tower, vacuum team observed that the ZnSe viewports show patterns as visible in Fig. 1 and Fig. 2 (Fig. 1: diagnostic viewport, Fig. 2: PAM viewport). These patterns suggest a possible delamination of the optical coatings from the window surfaces. Part of the coating material has already been collected by the vacuum team and will be analyzed via Scanning Electron Microscopy (SEM).
By visual inspection performed by Antonio and the vacuum team, no cracks in the ZnSe substrate have been identified.
A preliminary inspection of the viewports at WE and NE has been carried out by the vacuum team. It is noted that, at the end towers, only one viewport per tower is present (unlike the input towers, where two viewports are installed). The viewports appear to be in acceptable condition from the outside, although visibility is limited. The pattern is instead clearly visible from the inner side of the tower.
A further inspection of the WI viewports will be performed by the vacuum team as soon as possible.

Starting from the 9th of April, Angelo pointed out some slow glitches appeared  in the VAC_TOWERIB_MG1_CH4 channel.

I ve taken the set of data from the 9th of April up to now and I ve automatically detected the gitches, see Figure 1.

I' ve then compute the rate of the glitches, figure 2, and I' ve tried to correlate them with some temperature probes that Maria provided me

namely 'ENV_IB_F0_TE2';'ENV_IB_F4_TE1';'ENV_IB_F4_TE2';'ENV_IB_F7_TE1';'ENV_IB_F7_TE2'

no correlation has been found with these channels

investigations still on-going

Today, after the dismountling of the two baffles in front of the mirror (HR side) by L. Naticchioni e M. Ricci, I applied First Contact on the payload HR surface.

Before applying the FC, I inspected a bit the surface and I could spot many dust particles (Figs. 1 to 2). I could also find a big scratch on the upper left side of the mirror (Fig. 3). Moreover, it was possible to observe by eye the big point absorber found previously with the thermocamera (VIR-0106A-26) roughly at 9 cm to the right wr.t. the center of the mirror (Fig. 4). Measuring it on the picture, a slight more precise estimation is 8 cm, instead of 9 cm.

Figs. 5 to 7  show the FC application process and the completed work. 

ITF found in UPGRADING Mode and DOWN State.
All times are UTC.
06:57 TCS Chillers refill (Ciardelli).
08:21 West arm large valves opened (Vacuum team).
From 09:02 to 09:07 TCS WI CO2 Power Checks (Operator).
From 09:26 to 09:29 TCS WI Thermal Camera References (Operator).

During the shift the West Arm IR was recovered and ALS green was checked (Spinicelli, Pinto, Casanueva, De Rossi, see #69072).
ITF left in UPGRADING Mode and DOWN State, measurements on the PR suspension ongoing (Boschi).

TCS WI CO2 Power Checks:

Today we have checked the green lock after the installation of the source in the EIB bench. The motivation of this action was to reduce the amount of fiber used in the propagation of the green, since the air conditioning in the Laser Lab was producing noise that was strongly polluting the error signals.

We first aligned the west arm and locked the infrared without major problems. Then we locked the green in reflection of the west arm, which locked without major problems as well. At this point we checked the signals seen by the PDs in teh central building (ALS CEB WARM BEAT 154MHz). There is no saturation, we have slightly improved the "mag", and the spectrum of the error signal that we used (_dFreq) has improved a lot at high frequencies where we were dominated by the air conditioning noise (see Figure 1). The rms has improved by a factor 4 (our-of-loop).

We will have to wait to have both arms to check the passage to CARM/DARM but the target will be to increase the UGF of these loops. In order to check that we are no longer limited by the ambient noise we will make a test of turning off the air conditioning.

After the successfull deploiement for the WEB NCAL , we continue to use this new firmware on WEB and NEB PCal system and for the NEB NCal one.

Below the list of the operations performed:

• WEB PCAL system
  • Update the DAC1955-SN11 (WEB_PCAL_DAC) located in the DBOX-SN49 with the v3r3 release for the FPGA firmware and the DSP code
  • Update the WEB_PCal_fast Acl server 
  • Update the WEB_PCAL_DAC part in the SWEB_dbox_rack DBox server and reconfigure it 
  • After these operations the WEB_PCAL loop was successfully close
  • operations performed between 2026-05-05-06h49m50-UTC and 2026-05-05-07h27m54-UTC 
• NEB NCAL and PCAL systems update
  • Update the VPM Online configuration to use the DaqBox v17r9 for the SNEB_dbox_{bench,rack} servers
  • Update the DAC1955_SN6 (NEB_DAC_NCAL0) ) located in the DBOX-SN118 with the v3r3 release for the FPGA firmware and the DSP code
  • Update the DAC1955_SN18 (NEB_DAC_NCAL_TCS) located in the DBOX-SN119 with the v3r3 release for the FPGA firmware and the DSP code
  • Update the DAC1955_SN121 (NEB_DAC_PCAL) located in the DBOX-SN35 with the v3r3 release for the FPGA firmware and the DSP code 
  • Update the NEB_NCal server configuration
  • Update the NEB_PCal server configuration  and  the NEB_NNC_Tilt server configuration
    • these 2 servers are sharing the same DAC1955_SN121 (NEB_DAC_PCAL) but each one sends a Tolm packet  related to its used channels
  • Update the SNEB_dbox_rack configuration to set the related DAC1955 boards configuration
  • operations performed between 2026-05-05-08h28m20-UTC and 2026-05-05-09h39m12-UTC
  • After these operations only  the NEB NCAL loops were tested and all were successfully closed 
  • for the NEB_rtpc, the output data flow related to the DAC1955 boards was reduced from 29.4MB/s to 19.3MB/s