Minutes of the Geneva AMS group meeting on July 18, 2000


Geneva AMS group meetings

Mechanics

Eric Perrin informs about the reinforcements arrived from SITE, 4x7 and 4x15. Their quality is good. Also had arrived 4 spacers (12) that their quality should be improved.

The contract between ASI and SITE is not signed yet and it will not be signed before September. Eric asks if he will take some actions to obtain reinforcements (bricolage of old ones, etc). It has been decided not to 'bricolage' anything for the electric prototypes, even if this cause a delay (in any case there are delays.... see later)

Eric also presented the schedule for the integration, including the AMS dismantling. This schedule has been sent to Aachen to confirm it. So as you see first plane will be in Geneva for integration not before April/May 2001.

Vibration test. Most likiley will be done in Aachen whitout local support (to be confirmed) Davide and Eric will be in charge of these tests. We will 'vibrate' the quarter plate, mechanical ladder(?), thermal bars and flight hybrids (v2.0 or 2.1).

Upilex

No news from Cicorel. PL also present the possibility for a consultancy that has been rejected. Eric ask for the exact Gandi kapton production. In a couple of days PL will send the kapton available at Perugia.

Thermal studies

Divic has presented the last thermal studies with hybrids v2.0. The setup used is here. The results are summarized in this transparency. The measurements has been down with a "dry" contact and with sigraflex between S+K hybrids and K+box and with K+box with thermal grease. The results shows that sigraflex decrease greatly the temperature both on S and S sides by 5 degrees. If instead of sigraflex there is therma greas between K+box an additional degree is decreased.

Divic has also essay to get a 'feeling' of the true temperature on the silicon sensors. To study this he has figured out this network. Numbers there are thermal resistances (in W/C I hope). As you seen there is still a lot of unknowns. It has been decided to ask Bart Verlaat to compute/measure it.

Silicon

Due to a cut on the funding the Micron contract has been abandonned.

Electronics:

Giovanni informs us of a big delay on VA delivery. AMS (foundry) has delayed the VA production till the end of this year. IDEAS is trying to redece it, but very optimistically VAs will be available in 12(production)+2(assembly) from now, that is the end of october!!! This delay is going to be used to test hybrid +readout chain "before" assembly.

With respect to hybrid the flight model is now v2.1. Mechanically is exact to the 2.0. The only difference is the change of a transistor.

Next week there will be a meeting in Geneva with IDEAS assembly line responsible. 2 pairs v2.0 will be given to him.

Digital part of the test system has been built and is now working. The analog design will be finished this week and produced two prototypes with S and without S decoupling. IT is foreseen to have these boards in two/three weeks from now.

Prototypes

First mechanical prototype built at Geneva M12GT001 M=mechanical T=test)that will be sent asap to CERN for bonding. It has been notice a possible displacement of few microns in the gluing jig... Investigating. Further schedule for mechanical prototypes are M09GT002, M10GT003, M11GT004 and maybe M15GT005.

After this it will be built a couple of electrical prototypes that will go on the 30th august test beam. This ladders are E12GT010 (E=electrical) with 12 ladders and hybrid v1.8 (AMS1 like) and E02GT011 2 ladders long with hybrid v2.0 to test the new readout electronics. Sensors and Upilex has been asked to Perugia to built them. THe rest of the components are just now available at Geneva.

Future Meetings:

E. Cortina, Jul 6, 2000