I was able to lock back the FP-cavity.

at one moment, during the alignment optmization process of the infection mirrors of the FP-cavity, I had a huge misalignment moving Ma-Y motor.
I had to realign a lot this motor to get back to the standard power inside the FP-cavity.

=> maybe one needs to make some "walking" procedure on the alignment mirrors to get the best alignment => to be done

presently, the lock @32% of amp ratio produces 50kW inside the FP-cavity.
CH0 Smaract motor = 107µm
CH2 Smaract motor = -113µm
​

finally I installed the OneFive laser, the Smaract motors of the laser and the Arduino Peltier controller of the laser on the UPS plug.
the power "seen" by the UPS is 0W, perharps because the used power is below 100W.
the UPS says it can last 385mn (> 6h) in case of power shut down.

I had to do 10mm step at 10mm/s speed on CH0 of the Smaract motors to get back the laser modelock.
then, I put back the CH0 position at +140µm and the CH2 position at -177.8µm on the Smaract motor.

the present level measured by the laser amplifier is 3.05mW after the power ON of the laser @ CH0=0µm
the level measured by the laser amplifier is 3.012mW after the power ON of the laser @ CH0=+140µm

the level measured by the laser amplifier is 3.125mW after the power ON of the laser @ CH0=+140µm when we switch ON the preamplifier
then, we are able to check the laser repetition rate @ 33.383MHz measured by the amplifier software.

Jean-Noel Cayla installed several days ago a Eaton 9PX 11kVA UPS inside the Igloo, outside of the ThomX bunker
and I asked him to place only 1 UPS plug on the wall close to the FP-cavity to supply only the NKT/OneFive oscillator and the Smaract laser cavity motors.

I checked that if I plug a device on this UPS plug, I'm able to follow the power, used by the device, on the UPS monitoring screen.

thus, this morning, I plan to switch off the laser oscillator and move its power cable from a standard plug to the UPS plug and test if we are able to find back the previous performances of the locking.

the present Smaract motor positions are : CH0 => +140µm / CH2 => -177.8µm
as unpowering the motor will put the read position at 0µm, I first go back to 0µm for both channel.
I will put them back at their original values after I plug the motors back to UPS.

since around 2 weeks, the airflow above the optical table housing has a power breakdown when one tries to switch it on.

the power breaker is in the electrical bay, on the left of the south entrance of ThomX.
the name of the power breaker switch related to the airflow is "TABLEAU ANNEAU 4".

today, with Kevin, we switched off all the airflow boxes 1 by 1 to find the defective ariflow box :
when we are face to the optical table housing panels, it is the third one from the left on the rear side.
this airflow box has been switched off (all the airflow boxes have a individual switch).
now, the airflow can be switched on again without any issue.

one needs to order 1 replacement box + some spare ones => mail to be sent to the AirC2 company.

after finishing the controlled intervention, you just have to exit the bunker with the 2 keys and place them back in their location

then the controlled access (colored yellow) will turn to "access interdit" (red colored)

to terminate the closure of the bunker, you just have to turn the two key indicated in the previous image back to their original position.

If one needs to work with 3rd stage on the laser amplifier, one needs to make the safety patrol inspection before closing the bunker.

for that, it is mandatory to switch 2 keys on the "key board" in the control room, just before or just after the safety patrol :
- the THOMX key to 1
- the "EXPLOITATION LASERFP" key to 1

for the safety patrol, one has to push the "blinking white" buttons on the walls of the bunker, in the order from 1 to 6, and finish by the south entrance door button.
message " ronde en cours" is shouted during the process.
at the end of the safety patrol, an alarm is triggered for 30sec approx. and then stop.
now, the special keys located at the south entrance door are green and one has to take them (at least 2) to enter the bunker without breaking the safety patrol.

Adding the instructions manual for the Alphanov Amplifier SMC Chiller

Installation and Maintenance Manual Water Cooled Thermo Con for Rack Mount HECR Series

this afternoon, because of the test on the electron beam drive in the ring in the next days,
I removed the scope and the desktop computer (but not the display) installed close to the ThomX optical cavity.

they have been stored in the "Viktor" ThomX optical room.

This morning, I started the chiller and opened the valves on the external water circuit => no water leakage during the morning.

now, the chiller will stay ON all the time => we will check the installation at the end of the afternoon.

- this morning the chiller leakage has been fixed by adding some Teflon on the faulty Swagelock adapter.
a long leakage test has to be done to be sure there is no leakage at all => can be done on Friday during our tests.

- here is a picture of the 2 Alphanov amplifier controller interlocks.
I2 has to be connected to the Sub-D15 connector of the SMC HECR008 chiller

- this morning with Aurélien, we filled the water tank of the chiller and we opened the water valves (last pipes on water arrival/departure panel).

there is no leakage on the external water circuit but there is a small one on one of the Swagelock adapters of the water circuit connected to the Alphanov Amplifier.
we will add some Teflon to remove the leakage.

- the chiller alarm can be connected to the interlock detection of the Alphanov amplifier (I2 connector).
we will have a closer look at the different connectors next time, as the Alphanov manual is not very clear on how to connect them together.

This afternoon with Yann:
- we changed the shutter base plate position to center the beam axis with the mirrors center => to be checked with the amplifier beam
- on the L-shaped arm, the axis along the cavity beam has been centered. it should be never moved !!! (it corresponds to the less accessible knob).
Yann confirmed the 2 other translation axis of the L-shaped arm follow the back plate position.
These 2 axis have been positioned to put the L-shape plate completely of the beam path.
- the panel of the housing which was shifted has been fixed. now, it is properly aligned.

This afternoon, an electrical operation will be done in ThomX, impacting possibly the casemate power supplies.

Then we shut down all the equipment.

this afternoon with Viktor, we redid all the power supplies connexions.

4x cables are now connected to the wall sockets.
- 1x extension cable for the mini-rack multi-sockets cable.
- 3x triple-sockets long cables (3.5kW each).

all other cables have been removed and replaced.

we brought the other half-rack next to the first one.

The One Five laser and its controller have been moved from PLIC to ThomX Iglo.

In preparation to Install the Amplifier from Alphanov

The new iris mounts fixed on the small cavity windows.

Need additional 2 irises.

In order to find the Alignment of the ThomX cavity, Yann built mounts that could be placed directly on the windows outside the cavity, where we can place an iris at the center.

The center of the iris on the mount corresponds to the center of the mirror.

4 were made, big one for the injection and 3 small ones for the other windows. 

The big one fits, but the small ones don't fit, as the heads of screws exceed the circle boundary.

A change to them will be done so that they will fit where they will be clipped from the side.

On Friday the 5th of November, ThomX suffered again from a power breakdown.

all the pumping systems had to be restarted.
this produced a vacuum level increase and the FP-cavity valves shut off for security reasons.

Today the vacuum level is good enough and the 2 FP-cavity valves have been reopened by Eric Mistretta.

as the vacuum level was good enough, I asked Eric Mistretta to open the 2 valves of the FP cavity.

He said the vacuum group made several tests during the last days, opening and closing these valves!
I asked him to not open and close them as it could release some dust on the mirrors.

Eric opened the valves in "local mode", using directly the valves controller (see attached image).
He was unsure of what could happen if he switches to the "remote mode"... the valves could be commanded to close again.
so, for the moment, one stays in "local mode".

after opening the valves, the vacuum level started to decrease inside FP-cavity :
9.7e-10 mbar for the left vessel
1.7e-9 mbar for the right vessel

Pressure is 1.4e-9 and 2.6e-9 mbar this morning.

During the weekend 23-24th of October, the lab and ThomX suffered a power breakdown.
All the pumping systems had to restart.

as a consequence, the pressure on Monday 25th morning was 4.3e-9 and 4.6e-9 mbar in the left and right vessels.

this morning, the Tuesday 26th, the pressure is 1.4e-9 and 3e-9 mbar.
now, these pressures are compatible with the opening of the valves!

A plot showing the descend of the vacuum in the mirror chambers (data to plot it obtained yesterday evening)

The regions where there is a drastic decrease is when the ionic pump was turned on.

Today in the morning the pressure was

• on the left                    :  1.3*10^-9 mbar
• on the right (sortie X)  :  4.9*10^-9 mbar

in the evening the pressure was

• on the left                    :  1.4*10^-9 mbar
• on the right (sortie X)  :  4.7*10^-9 mbar

Leakage test done in the afternoon.

The method :

• an atomic mass spectrometer is connected to the mirror chamber and a measurement is taken to see all the atoms and molecules in the chamber
• after a Helium gas is spread around the outside of the chamber
• there is a leak if there is a spike at Helium (4 amu)

Attached is a picture of the spectrometer plot.

Conclusion: No leak in the cavity and the pressure is expected to decrease in the coming days

The pressure now is:

• on the left                    :  1.6*10^-9 mbar
• on the right (sortie X)  :  1.4*10^-8 mbar

**Note: there is an increase in the pressure after doing the measurement, which is expected from the spectrometer bumping ions to do the measurement.

At 9h30 in the morning, the pressure on the mirror chambers is:

• on the left                    :  1.6*10^-9 mbar
• on the right (sortie X)  :  6.5*10^-9 mbar

it appears to have decreased significantly compared to the previous deccend !!!!!!

At 10h in the morning, the pressure on the mirror chambers is:

• on the left                    :  1.9*10^-9 mbar
• on the right (sortie X)  :  1.0*10^-8 mbar

Bruno mentions that the pressure on the left is descending too slow,  a leakage check to be done on Tomorrow by the vacuum branch.

At 15h30 in the afternoon, the pressure on the mirror chambers is:

• on the left                    :  2.0*10^-9 mbar
• on the right (sortie X)  :  1.4*10^-8 mbar

the pressure decreased by 0.2 in ~ 5 hours for right , but increased by 0.1 for left

not an accurate reading for the change over time

will need to get the pressure vs time graph from the control room. 

Reminding: the opening of the valves is the responsibility of the vacuum group only.

At 10h45 in the morning, the pressure on the mirror chambers is:

• on the left                  :  1.9*10^-9 mbar
• on the right (sortie X)  :  1.6*10^-8 mbar

The pressure for the mirror vacuum chambers needs to be ~ few 10^-9 mbar for the valves to be open to the electron ring (the rest of the vacuumed ThomX)

• When connecting the Ethernet cable from the hub to the computer, it must be connected to the correct one (shown in green arrow in photo), it is not the usual internet
• the Motor controllers are under the Cavity table.
• The last image shows the positions of each mirror (To be checked if they are actual readings)

Now, both vessels are pumped by an ionic pump (both Turbo pumping entrances have been closed).
the primary pump has been removed from the left vessel.
we kept the primary pumping on the right part "in case of".

Now, the pressure on the right vessel is 2.1e-8 mbar.
the pressure on the left vessel is stable around 1.9e-9 mbar.

after the WE, the right vessel vacuum level is 1.7e-7 mbar (primary + turbo pumps)

and the left vessel vacuum level is 1.8e-9 mbar (primary + turbo + ionic pumps)

I will ask Frederic to start the right vessel ionic pump.

This afternoon with Manar, we finished connecting FP-cavity mirrors motors and alignment mirrors motors to their 3 ISP controllers.
We also added an Ethernet hub on top of these controllers to merge the controller's connections to the computer.
We added some cable extensions to the alignment mirrors motors.

We tested the connection and the controlling software made by Didier.
We used the supervisor software as one needs the trick to bypass the Didier safety procedure embedded in its user's software (Chassis12.exe and Chassis3.exe)
We were able to move the motors (tested only upon the 4 motors of the alignment mirrors) but sometimes it seems we have some connection bugs which freeze the access to the ISP controllers.

After some hours of pumping, the vacuum level decreased properly on the left vessel (input mirror) but it seems to decrease slowly on the right vessel (end mirrors).
In consequence, Frederic has been able to start the ionic pumping only on the left vessel (+ Turbo). The right vessel is still pumped by the Turbo pump.
at 5 pm, the pressure was 1.4e-8 mbar for the left vessel and 1.9e-6 mbar for the right vessel.
Depending on the pressure on Monday, Frederic could start the ionic pumping for the right vessel too.

the ionic pumps have been also connected this morning but not powered on, yet.
the vacuum group is waiting for a vacuum level below 10**-6 to power them on.

it should be the case this afternoon.

about permanent cables on the optical table for the vacuum system, there are 2 for the gauges and 1 for the ionic pump for each vessel, then 6 in total.

• The electron ring has been vacuum inside it, but the valves connecting it to the two mirror chambers are closed. Before commencing to do measurements on the cavity, we must place the mirrors under the proper vacuum and open the valves connecting them to the electron ring.

• The vacuum system is consistent of three levels; Normal (max ~10^-3 mbar), turbo (max ~ 10^-7 mbar) and ionization.
• With the help of  Frédéric LETELLIER and Mercier Bruno from the vacuum department in the morning.
  • Installation of the first level vacuum (normal pump)
  • Installation of the second level vacuum (turbo pump)
    • can reach up to 1350 Hz = 81 000 rotation per min (how fast it reaches max rotation depends on how good the first level pump was done)
  • Installation of the connections to the gauge meter, there are two gauges, one for first level and one for second.
• All turned on !!

• Both are on and can be monitored from ThomX control room
  • The attached photo from the control room shows how we will be able to get a graph of vacuum over time.
    • (we were able to reach approximately for Volume 11 and Volume 12 respectively 4.1*10^-6 and ~8*10^-7)
      • to explain Volume 11 and volume 12 (look at Location of ThomX vacuum valves photo)

• A photo of the control module placed outside the bunker to control the optical cavity vacuum is attached
• This afternoon the third system will be installed and turned on

*** Note after vacuum is set there will be three permeant cables inside the cavity box for monitoring.

This afternoon, we continued to clean the housing with Manar and Daniele.
we did a dust measurement after cleaning with the two ceil doors opened and the dust meter in the middle of the table, and it counted ZERO!
it doesn't mean the housing is perfectly clean but it is clean enough to pay attention now to cleanness.

Then from today, we have to wear overshoes at the entrance of the ThomX casemate and wear clean coats below the airflow (we installed the coats inside the FP-cavity airlock).

for cabling motor controllers, we discussed with Aurélien about the Alphanov amplifier position on the optical table.
we don't have the last schemes... so, Aurélien sent an email to Guillaume Machinet and Yann to get them.
normally we could let the computer inside the casemate close to the optical table while the electron beam is not filled inside the ring.
as it is dumped on the opposite side of the casemate, the computer position should be radiation safe for now.

One half-height rack, close to the optical table, has few network devices BUT takes almost all the rack place!
we could easily fit the hexapod controller in this rack with "logical" cabling.

This morning with Manar, we started to clean the floor around the cavity, the outside part of the panels of the housing, and the optical table.
we will continue this afternoon and, in the end, we will make some dust measurements.
do we know who in ThomX is in charge of the cleanness of the casemate (bringing overshoes, sticky floor, cleaning company for the floor,...)?

the motors controller mini-rack has been installed under the optical table.
but it is still not connected to motors or computer.

we saw a chiller beside the optical table... is it the laser amplifier chiller ?

there is also the hexapod controller which is presently close to the wall.
do you remember where is the final place of this controller?

the two vessels of the FP-cavity are presently at room pressure with nitrogen inside.
it has to be put under vacuum (~ 10**-8) before opening the 2 valves which are separating the vessels from the electron ring.
we can't make any Finesse measurement until the vacuum is made and the valves are open.
we discussed with Bruno about that, and he is aware of the situation. He said he will try to pump the vessels as soon as possible
in order to be able to inject a laser on the next opening, next week.

The AC plug and the power cord of the airflow were quite hot because they have been dimensioned for 16A current and the total current is above.
AirC2 company should replace them with 32A equipment (6mm2 power cord + 32A Hypra AC plug) in the next days.
 

On the 27th of May, the Airflow has been dismounted from the optical room to be mounted around the optical cavity by the AirC2 company.

here is email from Yann :

Le flux est rentré dans la casemate.
Lundi la société AirC2 revient pour installer les rideaux.
Petits couacs :
- 2 plaques de faux plancher à découper
- le saut de loup à été déplacé (à voir si c'est OK pour tout le monde)
- filet de toit à retendre
- poutres du toit à remettre
- main courante du faux plancher à retirer
- attention au coin du flux au niveau du saut de loup (à baliser et protéger)

On the 19th of May, the optical table has been moved inside the ThomX concrete housing and connected to the Symetrie hexapod and to the electron ring.

Symetrie guys started to test the hexapod and they put some software limits around the predefined zero position.

Today, Yannick Petrilli removed 5 concrete bars (5-9) from the ThomX housing roof in order to let the optical table be installed on Wednesday with the help of Bovis and Symetrie.

The safety net above the equiments has been removed too (one had to remove the hooks on one side to be able to slide the net).

One steel guiding cable (on the right side of the picture) is still there "in the middle" and has to be removed before Wednesday.

This morning the Bovis company moved the optical table from the optical room to the Igloo without any problem.

The table is now stored inside the Igloo, just after the large entrance doors, on the right side.
It has been covered with plastic blankets.

Operations before moving the optical table from the optical room to the Igloo.

— the cavity has been filled with clean nitrogen to reach ambient pressure.
— the two valves have been closed using 5 bar air pressure to properly clamp them.
— the dummy tube between the 2 vessels has been removed and the 2 bellows have been protected with plastic covers.
— all the vacuum equipments have been disconnected from the cavity (only turbo and ionic pumps still remain).
— all the optical elements have been removed from the optical table (only some plates and empty mounts still remain, fixed on the table).
— all the electric cables have been removed when possible. Cables for cavity motors are difficult to disconnect from the vessel side due to the housing. They are still in place. Cables which cannot be removed have been fixed with adhesive tapes and/or clamps.

The optical table is ready to be moved by Bovis on the 26/02 to the Igloo.
 

19/06/2020

The first part of the edge installation was on done by Yann and Ronic
- close the 2 valves of the cavity
- stop the ionic pump on the edge side
- go to ambient pressure with the special filter
- install the edge on its moving arm
We stopped the installation because of a problem with the flange screws which are touching the moving arm structure => Yann modified the moving arm structure.

01/07/2020

Today, Titouan and Yann finished the installation of the edge in one of the vessels of the FP cavity (the vessel which does not contain the input mirror).
they fully cleaned the arm which holds the edge and goes inside the vessel to cut a part of the cavity beam to block the high order modes.
after closing the vessel, they start the primary pumping:

primary vacuum   : 8e-2 mbar
pumping duration : 1h30.

and then, they start the turbo pumping:

turbo vacuum : 6e-6 mbar
pumping duration: 2h30.

Tomorrow, they plan to wait to have a vacuum level, compatible with ionic pumping (below 1e-7 mbar), to start the vacuum ionic pump (only on the "edge side") and stop primary and turbo pumping.
the question is: what is the tolerable vacuum difference between the two parts of the cavity, to open the valves?
one has to ask the vacuum group for that.

02/07/2020

This morning, after a night with primary pump + turbopump on, the vacuum was between 1e-6 mbar and 2e-6 mbar.
at the end of the day, the pressure was still the same... it is the turbopump limit more or less.
Then, I started the ionic pump WITH protection ON, several times.
each time, the pressure increases a lot (to 1e-5 mbar) as the ionic pump releases particles, and then the protection stops automatically the ionic pump.

the ionic pump was started several times WITH protection ON until the maximum pressure is below 5e-6 mbar, then I remove the protection of the ionic pump to let the pumping process going below 2e-6mbar.
NEVER let the ionic pump without protection if you don't stay beside to stop it in case of.
once the pressure is below 2e-6 mbar, I put back the protection and the ionic pump HV is increasing to 7kV and the pressure is going down.
after 1h of all pumps working:

5 pm: pressure is 1.9e-7 mbar

Then, I closed slowly the valve between the turbopump and the cavity (the primary pump is still ON) and stopped the turbopump.
now, the ionic pump is pumping alone the cavity.

6.30pm : pressure is 1.3e-7 mbar

03/07/2020

This morning, I closed the valve of the primary pump, pumping the edge side, and stopped it.
8 am: pressure is 7e-8 mbar (on the edge side).

the other side of the cavity, closed by 2 valves, was around 1.3e-9 mbar.

3 pm: pressure is 6e-8 mbar (on the edge side).

The problem is to open the valve between the tube (which was not pumped for 2 weeks) and the "edge" vessel which was pumped by the ionic pump (6e-8 mbar).

With Frederic, we just stopped the ionic pump (the vacuum increased a little bit) and directly opened the valve on the edge side.
the vacuum raised above 1e-6 mbar and then we restarted primary and turbo pumps until we reached a level below 1e-6 mbar.
then, we switched on the ionic pump again and stopped turbo and primary pumps.

Now the edge side AND the tube are pumped together with the ionic pump alone.
Frederic advised me to tighten a little bit more the screw of the valve of the turbopump to avoid any leakage.

4 pm: pressure is 5.2e-8 mbar

Frederic changed the configuration of the ionic pump controller from "fixed HV" to "stepped HV" to adapt the HV to the level vacuum (if the vacuum is good enough, the HV is automatically decreased from 7kV to 5kV or 3kV to improving pumping efficiency).

Frederic mentioned also the possibility to use mass spectroscopy installed on the cavity to make some leakage measurements with a Helium bottle.

06/07/2020

Today, after pumping all the week-end with the ionic pump, the vacuum was 1.5e-8 mbar.
I opened the second valve and the vacuum changed to 1.2e-8 mbar.
Now, the cavity is completely open and pumped by the 2 ionic pumps.

07/07/2020

09:00 am: pressure is 7.3e-9 mbar
16:30 pm: pressure is 7e-9 mbar

08/07/2020

09:00 am: pressure is 6e-9 mbar

10/07/2020

11:00 am: pressure is 4.2e-9 mbar

13/07/2020

06:00 pm: pressure is 3.2e-9 mbar

15/07/2020

04:00 pm: pressure is 2.8e-9 mbar

A new circuit breaker has been installed today before the UPS to fix the shutdown issues we observed some months ago when too many devices are connected to the UPS.
it has to be tested...

The Pneumatic valves are still coming back to "close" position.
Now the air bottle is always "open" to keep the valves "open".

The 30Hz noise is still here. We tried to cut off all the air flows. It only decreased the noise intensity but didn't change its shape.

21/11/2019 :

The pneumatic valves are now connected permanently to the university airflow network.
there is a small air leakage but it is not an issue anymore.

the 30Hz noise has been fixed too as it was coming from the extreme position of M1 and M4 (plan mirrors) and due to mechanical instability in this position (motor "outside")

Today, Manu and Eric changed the cavity valves pressure system to open and close them.

during the lock of the OneFive+Amp or of the Koheras, we saw a very noisy PZT signal at 30Hz with increasing/decreasing amplitude very slowly.
this noisy signal was not seen at the begining of the experiment.
as it is independant of the laser source, we guess it should come from the cavity.
at this moment, one only see these valves (which tend to close by themself when there is some leakage) as a source of frequency noise.
we will see if, with this cabling change, the noise on the PZT signal changes also.

Scheme of cabling of the SmarAct motors controllers for acting on Frep and CEP.

Today, the chiller worked at 17°C during 3 hours without error, no freezing nor flow sensor error.

We observed 2 issues for the chiller of the new CELIA laser amplifier:

• setting the water temperature to 17°C, the chiller water turns to ice close to the water filling port !!! => temperature too low ?
• even when the water is fluid, one has a flow sensor error ! => pump charge too strong ? => reduce the water pipe length.

We have set the water temperature to 20°C and we shortened the water pipes by 2-3m

         => both problems seem to be fixed.

Now, we can try to reduce the setting temperature.