For the enlargement of the VRS network @WE it was worth confirming the survey done (eLog 69010) with another independent one, carried out with classical tecnique by theodolite and post-processing by compensation software, as we did in the past for all the reference points installed in the Virgo Experimental Buildings (see also VIR-0523AF-13). During last Mar31-Apr1 we carried out the survey by teodolithe Leica TDA5000 and then the analisys of the raw data by compensationt software StarNet.

Tab1 reports the final result of the compensation obtained showing the VRS coordinates, the standard deviations and the parameters of the relevant error ellipses port the new reference points considered.The resuls obtained are perfectly coherent with those deriving from the laser tracker survey, so that the coordinates of the new points are validated.

Fig.8 reports the whole scheme of the survey carried out, with the graphical indication of the error ellipses, while Fig.1 to 7 shown some pictures of the survey carried out.

Following the installation of the new reference points @WE building (placed on the concrete walls of the building and on the tower floor), last Feb24 it has been carried out the survey with the laser tracker Leica AT403 in order to estabilish the new coordinates of the reference points.

We performed 3 different measures for each of the 5 station in total, at different positions in the building. Each measure has been processed with the Best Fit technique.

Tab1 summarizes the result of the survey in VRS coordinates, while Fig.7 reports the scheme of the survey for one of the stations (S05).

Fig.1 to 6 shown the pictures of the survey carried out and some of the new reference points.

Yesterday, due to the pumping transient, V coils were going towards saturation, we opened the V loops.

Today position of vertical filters have been recovered through the use of the motors.

SR is now back in standard control configuration (TOP H+V pos and inertial, F7 and LC controls).

By adding about 10 kg of counterweights we managed to get an acceptable poisiton of the EIB and managed to close the loop. Some actuators are quite at the limit. 
We will work on the balancing tomorrow with Henk Jan to put some of the counterweights on the bottom part and get a healthier situation for the bench.

THURSDAY 

WI PAM 
This morning, we replaced our LED with one kindly provided by the EGO optics group, as the one we brought from Rome was too weak and might not have been visible inside the tower. To be on the safe side, we also verified that the red LED light passes through the ZnSe viewport using a spare window (see Fig. 1). After that, we switched on the heater to align the beam with the new LED.

We then proceeded with the installation on the tower base. During the installation, it was noticed that the LED mount prevented the actuator from reaching the nominal distance to the viewport. The actuator was therefore removed and the LED mount was modified (the final configuration is shown in Fig. 2). At this stage, the LED was realigned to the thermal radiation by applying V=6.8 V I=4. 2 A reaching a temperature of about 670 °C (see Fig. 3-Fig. 4).

The installation on the tower base was then repeated and successfully completed (see Fig. 5). Once the actuator was correctly positioned, it was secured to the alignment plate using clamps.

The cabling, including the remote powering of the actuator and the operation of the picomotors, was tested after completing the installation.

The WI PAM actuator was left OFF, with the power supplies ON, the maximum current set to 8 A, and the output voltage disabled (see Fig. 6).

NI PAM

At this stage, we moved to the NI HR side. The NI PAM was removed in order to install the alignment layers on the tower base. To perform this operation, the tripod supporting both the camera and the thermal camera was moved. The alignment plate on which the tripod is now placed has a thickness of 18 mm; therefore, both cameras need to be realigned and refocused (see Fig. 7).
The NI PAM was left near the NI CO₂ laser bench, inside the white tent marking the laser hazard area.

Today we installed all the optics on the EIB, without aligning them, in order to let Henk Jan rebalance the bench.

Pictures 1 and 2 show the optics added. The list with the corresponding weight are in the attached pdf.

The total added weight is around 12.2 kg.

We removed from the EIB some other optics no more needed (a mirror and a density). A beam dump of 960 g was replaced with a 255 g standard mount, so the total removed weight is around 750

Yesterday afternoon we started the installation of the LB-EIB pointing, as shown in the block diagram on Fig. 1. After removing all the old components and the old IBMS system, yesterday evening we finished to install the new mirrors after the PMC on the laser bench (Figs. 2 and 3) and to take some references for the beam. Today we installed also all the optical components on the EIB. 

Here a list of the new components on EIB and the weight of each of them:

1. M1a - 516 g
2. M1b - 772 g
3. M1c - 516 g
4. L1 - 173 g
5. L2 - 173 g
6. PT_M1 - 430 g
7. PT_M2 - 430g
8. QPD NF - 1360 g
9. QPD FF - 1360g
10. clamps and screws - 625 g

The total weight is 6354 g. We did a rough alignment but the fine alignment is going to be performed once EIB is rebalanced to have the right position of the main beam. Attached some pictures before (Figs. 4 to 6), and after the installation on EIB (Figs. 7 to 10). 

ITF found in UPGRADING mode and in DOWN state
The planned activities went on without major issues:

- Free space ALS / LB->EIB pointing (De Rossi, Spinicelli, Lagabbe, Melo, Gosselin)
- NI cryotrap repair (Vacuum Group)
- WI PAM installation (Nardecchia, Aiello)
- DMS maintenance (Berni)

The TCS_PAM_WI_PowerSupply server was launched yesterday at 13:45 UTC. Data has been archived to the DAQ since 14:10 UTC. For unknown reasons, after 15:00 UTC, there is a data gap of about 10 minutes (see figure1). After that, everything seems to be working properly (see figure2).

This afternoon we could start the work on ALS.

• We switched off all the ALS is in the Laser Lab atrium (taking notes for the cabliing): 

1064 pd alim L.2.4 DCF 21   (lemo adc 3 orange)
534 pd alim L3.1 DCF 21     (lemo adc 6 blue)
West beating RF PD alim  L3.2 DCF 21  (sma cable 2 atr-piscina 15m  lemo adc 5 green)     fiber EIB atrium B 14m
North beating RF PD alim L3.3 DCF 21   (sma cable 1 atr-piscina 15m  lemo adc 4 yellow)  fiber EIB atrium A 14m

Box ALS Ctrl PD alim 1 L2.2 DCF21                (lemo adc 1 brown)
Box ALS Ctrl flip mirror alim 1 L2.3 DCF21

• Installation of some of the optics on the EIB.
  • We removed extra weight from the EIB (3 flip mirrors from IBMS, for a total weight of 1.55 kg).
  •  Since we do not have the main beam pickoff available yet, we installed a fibered laser at 1064 nm for alignment and we started to install some optics.
  • The goal is to move the setup from the SHG box (pict 1 and 2) on the EIB (we cannot simply move the whole 40cmx50cm bench because its own weight is more than 20kg. Moreover the height of the beam in the box is 7.5 cm while on the EIB is 10 cm)

To be continued...

Roberto and Federico completed the cabling of the WI PAM source, both at the actuator level and in the TCS room, to provide power and enable temperature monitoring (see Fig. 1).
The temperature of the heater is available under the channel INF_TCS_WI_IntHeater_TE.
 
In the afternoon, Elian completed the ethernet cabling for the WI PAM power supply in the TCS room, while Giulio set up the process on the VPM to control the switching on and off of the WI PAM actuator by setting the desired voltage (see Fig. 2).

Giulio also integrated the data to monitor the applied voltage, the current drawn by the actuator, and the applied power, which are now available on DD under the following names:

• TCS_PAM_PowerUnitWI_Heater_p32_curr
• TCS_PAM_PowerUnitWI_Heater_p32_volt
• TCS_PAM_PowerUnitWI_Heater_p32_power

! The data are available online but we are not able to see them in the DD (see Fig. 3).

After completion of the cabling activities, the following actions were performed:

• Alignment of the LED with the thermal radiation emitted by the heater

• Installation of the alignment mask (“smile”) in the optical path and verification of its focus at the nominal position of the WI HR surface. Figure 4 shows the “smile” for lens L2 in two configurations: the left image corresponds to a non-optimized lens position, while the right image shows the smile in the optimized lens configuration.

The actuator was operated at V = 6 V and I = 4.1 A and the temperature of the heater reaches 600 °C (see Fig. 5).
Tomorrow we will proceed with the final positioning of the WI PAM actuator on the tower base.

ITF found in Upgrading mode and in Down state.

- SR loops still opened after the susp intervention.
- SDB1 and SDB2 loops still opened

The planned activities went on without major issues::

- Free space ALS / LB->EIB pointing
- NI cryotrap repair
- WI PAM installation

The  EER_DBOX1_ADC{1,2} ADC2378 configurations have been updated  and downloaded

• to acquire the ALS_CEB_{N,W}ARM_QD{1,2}_{SUM,H,V} channels and
• to make these new channels available on the ALS_CEB_rtpc
• operations performed between 2026-04-15-09h39m22-UTC and 2026-04-15-09h49m49-UTC

The output of FdStat command returns: 

====GTimeS: 1460281947 =============================================================================================
 V1:ALS_CEB_WARM_QD2_V                    nData=  10000 min=      -555  mean=     -536  max=     -515 rate=  10000Hz
 V1:ALS_CEB_WARM_QD2_SUM                  nData=  10000 min=  1.94e+03  mean= 1.96e+03  max= 1.97e+03 rate=  10000Hz
 V1:ALS_CEB_WARM_QD2_H                    nData=  10000 min=  3.47e+03  mean= 3.49e+03  max= 3.51e+03 rate=  10000Hz
 V1:ALS_CEB_WARM_QD1_V                    nData=  10000 min=      -595  mean=     -578  max=     -559 rate=  10000Hz
 V1:ALS_CEB_WARM_QD1_SUM                  nData=  10000 min=  1.93e+03  mean= 1.95e+03  max= 1.97e+03 rate=  10000Hz
 V1:ALS_CEB_WARM_QD1_H                    nData=  10000 min=       169  mean=      187  max=      206 rate=  10000Hz
 V1:ALS_CEB_NARM_QD2_V                    nData=  10000 min=      -110  mean=    -88.2  max=      -69 rate=  10000Hz
 V1:ALS_CEB_NARM_QD2_SUM                  nData=  10000 min=  1.27e+03  mean= 1.29e+03  max= 1.31e+03 rate=  10000Hz
 V1:ALS_CEB_NARM_QD2_H                    nData=  10000 min=      -455  mean=     -437  max=     -418 rate=  10000Hz
 V1:ALS_CEB_NARM_QD1_V                    nData=  10000 min=       414  mean=      431  max=      448 rate=  10000Hz
 V1:ALS_CEB_NARM_QD1_SUM                  nData=  10000 min=  1.87e+03  mean= 1.89e+03  max=  1.9e+03 rate=  10000Hz
 V1:ALS_CEB_NARM_QD1_H                    nData=  10000 min= -1.06e+03  mean=-1.04e+03  max=-1.02e+03 rate=  10000Hz

Today we kept on the preparation for the installation of INJ-ALS upgrades. 

- all the cables have been installed

- we found a leak in the system to block the EIB bench. Fabio found a patch for this using compressed air from vacuum instead of the nitrogen bottlles (which are small and last half a day with this leak)

- then we wanted to recover the BPC, which was not working from the 12th of April. In order to do so we add to rebalance the EIB. We removed the extra weights which were present on the EIB (4 kg overall). We then added some weights to mimic all the weight of the optomechanics removed yesterday (+ those extra 4 kg). We could suspend EIB, and after a couple of recompilation of the DSP of the BPC from Valerio (at the beginning the signals from the piezos were missing) we could close the BPC loop

- we did not manage to close the IMC automatic alignment, and this will be the first activity to do tomorrow. It seems that the NF QPD demodulated signal is not working

During Monday afternoon:

• The alignment plates were retrieved from the washing room.

• The IPATSiA optical bench was moved from the WI tower base to the optics lab (see Fig.1)

• In parallel, the cabling of the picomotors was carried out in the TCS room by Giulio and Elian

On Tuesday:

• The alignment plate was installed on the WI tower base together with Alessio B. and Angelo (see Fig. 2)

• The LED setup used to ease the alignment on the HR surface was also integrated on the actuator (see Fig. 3).

• The picomotors were cabled on the actuator side using CABLE 003 (TX) and CABLE 004 (TY).
  Finally, a remote driving test of the picomotors was performed with Giulio, confirming proper operation.
  Specifically, from the VPM interface:

  • TY+ → move the beam to the right on the HR face
  • TY− → move the beam to the left on the HR face
  • TX+ → move the beam upward on the HR face
  • TX− → move the beam downward on the HR face

• Then, the picomotors have been calibrated using the LED to the nominal actuator-TM design distance [Actuator–TM distance = 1126.5 mm | Height between the actuator base and TM center = 681.3 mm, as shown in Fig. 4].
  We estimated:

  •  1 cm on TY =6666 steps
  •  1 cm on TX =5555 steps
• The movements of the picomotors are available on DD (see Fig. 5).

Tomorrow, we plan to complete the final cabling of the source and to align the thermal radiation to the red LED.

ITF found in Upgrading mode and in Down state.

Below the list of the activities communicated in control room:

• from 6:00 UTC to 10:00 UTC standard maintenance:
  • cleaning operations of the experimental areas;
  • TCS chiller refill;
• INJ - ALS upgrades: still in progress;
• SR diaphragm removal: in the morning Ettore and Manuel performed the final checks inside the tower. In the afternnon the vacuum team started the evacuation procedure.
• WI PAM installation: still in progress; 
• NI cryotrap repair: no info about this activity.

This morning we started the activities in laser lab by:

- adding new cables for signal and power supplies between EIB and atrium

- adding electronics for QPDs in LL atrium

- we moved the als fiber for the pickoff from Atrium-DAQ room to LL - DAQ room

- We freed sapce by removing all the optics of the unused Phase camera and IBMS that were on the south part of EIB. 
In total we removed about 21kg (see list attached) and the dedicated picture (with and without labels, from 1 to 4).  

- add the ADC channels for both ALS and INJ QPDs (ALS part commented for the moment). We used the mezzanines already available in INJ Eeroom and we added the channels in INJ_dbox_EEr. The modifications to the cfg file are the following:

**** FOR INJ QPDs ****

DAQ box 123 , ADC2378_SN 194

• we moved ch 00 (free) et ch01 (PMC Pmonit refl) to SN_186 ch 06 et 07 

• ch 00 et 01 (they was PMC Pmonit Pin et Pmonit refl) have been named INJ_BPL_QD1_SUM et INJ_BPL_QD2_SUM

DAQ box 123 , ADC2378_SN 199

• ch 00, ch 01 Pstab pressure replaced (not used) and named instead INJ_BPL_QD1_H et INJ_BPL_QD1_V

DAQ box 123 , ADC2378_SN 206

• ch 06, ch 07 INJ_BPL_QD2_H et INJ_BPL_QD2_V

**** FOR ALS QPDs ***

we used DBOX_SN123 (EER_DBOX1) and receive the data on rtpc10 (ALS_CEB)

• ADC2378_SN194 (EER_DBOX1_ADC1): 
  • ch 02-03-04 :  ALS_CEB_NARM_QD1 (DC_Sum, DC_H et DC_V)
  • ch05-06-07 :  ALS_CEB_NARM_QD2 (DC_Sum, DC_H et DC_V)
• ADC2378_SN199 ((EER_DBOX1_ADC2)
  • • ch02-03-04 :  ALS_CEB_WARM_QD1 (DC_Sum, DC_H et DC_V)
    • ch05-06-07 :  ALS_CEB_WARM_QD2 (DC_Sum, DC_H et DC_V)

ITF found in UPGRADING Mode and DOWN State.
All times are UTC.
07:30 QPD installation begin (Gherardini, Menzione, Erbanni, Nenci, Cavalieri, Melo).
07:40 - 07:54 SBE_SPRB_ACT_F0V recovery (from -5.2 V to -0.5 V acting on motor_3).
07:58 Closed SBE_EIB loops.
08:00 SR diaphragm removal begin (Majorana, Pinto).
01:14 Set INJ HVAC on nominal flow rate ("Portata Nominale"), an issue prevented the "Mandata" to go on full full flow rate, then Soldani went on the inverter and set it manually, since the works in INJ LAB will go on during the week the operativity at reduced flow rate ("portata ridotta") will be restored at the end of the activity in INJ LAB.
02:27 Engaged MC_Guard after investigation on MC glitches (Boschi, Pierdibene, Ruggi, #68988).
15:20 SR diaphragm removal concluded (Majorana, Pinto).
ITF left in UPGRADING Mode and DOWN State.

The issue was due to a fake contact of the Marionette DSP board #2 (serial #51172) in the crate. Today after removing and re-inserting the board from the crate the glitches disappeared from TZ correction signals. On the other DOFs this has been confirmed by changing the DC of the correction signals with the motors: no noticeable effect was apparent.

Venting of SR tower is in progress

At 20:05 UTC, the SR ring heater was switched off.