Re: visits to PSI - status TPC

[Claude Petitjean <claude.petitjean@psi.ch>]

Dear Alexei,

thanks for the travel plans. As agreed, PSI will accomodate the
guest house and the travel allowance. If visas need to be issued by
PSI, please let me know. (I will be absent from end of July on during
the first 2 weeks of August.)

Unfortunately, the status of the tpc is still not optimal. As you know,
we got some hot spots in 10 bar protium after reaching 6.5 kV. They
brought us back to a voltage below 4.4 kV (protium), while in 5 bar
Nitrogen we reached stable condition at 5.5 kV, where we can use the
tpc as an ideal muon stop monitor.

Tomorrow we plan to fill the chamber again with protium. We can now
run the 2 cathodes with independent voltages, but a test in Nitrogen
has already shown that the hot spots break out at an average voltage
by the 2 cathodes, which remains approximately the same as before.

Our plan is, after the protium test to open again next week the TPC
vessel and inspect the anode and cathode planes. After that, we will
need to make some hard decision what to prepare for a production run
for mid August to September.

With best regards

Claude

Alexei Vorobyov wrote:
> Dear Claude and Peter,
> As you already know
> V.ANDREEV and A.FETISOV will stay till July 22 .
> I believe they will prepare the SINDRUM for installation of the
> electronics.
> G.PETROV is coming on July 13 till Sept 28. He has already air tickets.
> G.SEMENCHUK ,E.MAEV,O MAEV  will come around August 1 till Sept 28.  
> They all have invitations from CERN. Their subsistence will be paid 
> from our CERN budget (note that with these visits the budget will become
> zero)
> I hope that PSI,as before, could provide the gest house and
>  compensation for tickets.
> 
>                              With best wishes for the next run
>                                                     Alexey