DRAFT version, 11Nov

Minutes of the Vac meeting of 7Nov, EGO site .

Presents: A.Chincarini, G.Gemme, A.Rocchi, R.deRosa, J. van den Brand, D.Martin, C.Bradaschia, A.Pasqualetti (minutes), A. Paoli, T. Zelenova, H.Heitmann (part time), P.Popolizio (part time), F.Carbognani (part time).
Remotely connected: none

The scope of the meeting is to discuss and share the work to be done, in particular for the end December
Agenda
_ introduction A.Pasqualetti
_ vacuum upgrade A.Pasqualetti
_ cryogenics J. van den Brand, G.Gemme, A.Rocchi
_ towers displacement F.Richard
_ links enlargement C.Bradaschia
_ SR upgrade P.Mugnier postponed
_ UHV air improvement P.Mugnier postponed
_ control system LAL postponed
_ other contributions (vacuum compatibility tests... )
_ work organization


Review output: they want estimation of costs, manpower needs, and time plans for the realization of each task; for all the AdV subsystems. See presentation of G.Losurdo at the Nov Virgo week. The next meeting with review panel will be the 09Jan about organizational aspects; slides to be posted within the 30Dec.

Preparation for the next review meeting:
Need to establish the format of the answer together with the other Adv subsystems.
Need to fix a reference design to be associated with the realization plan asked by committee (for instance the position and the geometric dimension of cryotraps …). Clearly the design cannot be frozen now.

Work sharing about the task ‘vacuum upgrade – cryotraps’
_Genova team shall continue carrying out general vacuum calculations. It will contribute also studying the LN2 supply plant, considering a possible closed loop design.
_Nikhef is engaged in cryotraps. Starting from a first reference model, design has started evaluating different constructive options. Also related vacuum calculations are in progress. EGO will send asap to Nikhef the pertinent technical drawings and other documents useful for designing the trap .
The proposal for the reference cryotrap geometry is attached.
_Roma2 will take care of evaluating the thermal effects induced by cryotraps on principal mirrors . A first check shall be done soon. In particular the smaller cryotrap option shall be cheked too (geometry to be sent to Alessio).



Others tasks:

Links and tower displacement: Some preliminary work exists. Carlo showed a new idea about having very large links (1m) with small vacuum valves (600mm), possibly advantaging for glass baffles installation. Reference tower link diameter is 600mm with valves of 600mm size between SR-DT and PR-IB and 500mm size for the other towers.

UHV clean air & SR tower. Main design options and cost estimates are defined or rather delineated. Discussion is postponed to the next meeting with Lapp team, normally 24Nov.

Control system: postponed. Urgent to have a meeting with Lal team. Need also to start the interfacing with DAQ subsytem to discuss about the common characteristics of AdV electronics.

Tests of vacuum compatibility: peek . In the hypothesis of TCS with ring heater, the peek could undergo up to 80C. It has to be characterized also at those temperatures.


Proposed date for the next meetings: 24Nov in the morning. Others: 5-9Dec, 19-22Dec