Tile Calorimeter

Test Beams periods in 1997

Page maintained by: I.Efthymiopoulos (last update: May 19, 1997)

Schedule

^{Machine development days: 2 July (8:00-16:00), 9 July (8:00-16:00), 23 July (8:00 - 16:00)}

^{We have allocated this test beam period, but we might not use it if all go well with the SPS schedule}

Special beam requests:

• 3 shifts for low energy running (20, 10 GeV as in the past, and perhaps an even lower energy point between 10 and 5 GeV),
• and 3 shifts for high energy running (300, 400 GeV)

The exact times for the special beams will be discussed again following the genaral SPS schedule.

Installation plan

• The modules are expected to be at CERN fully tested in June. According to the latest information it is possible that both modules will be at CERN during the first week of June.
• Each module when arrives at CERN is checked that no damages are made during transportation, and is put directly on the scanning table.

Note: For the ANL module the tubes and connections for the Cs Calibration have to be installed before the module is put on the table.

• The two drawers which were send to the two assembly labs will go irst to CF for general revision and to be completed (PMTs, light guides, cooling etc...), and then they wil be back at CERN for installation in the test beam. They are scheduled to be at CERN on the June 9th.
• A first proposal for time allocation during the run preparation is shown below:
• June 6th - June 16th: Complete installation in H8 (including the Cs calibration system)
• June 17th - June 22nd: Source calibration, HV adjustment.
• June 23rd - June 28th: Laser and DAQ debugging and electronics calibration
• June 28th - July 2nd: commissioning

Module Configuration on the Scanning Table

There have been several proposals/possibilities for the installation of the two extended barrel modules on the scanning table. Here is the list followed by some comments.

• Proposal 1: This is the old proposal for the module configuration that was presented in the March ATLAS week .

3d view of the module setup on the table.(beam left is on the left of the figure) The ITC plug is on the left side of the modules but not shown here.

It has the dissadvantage that the top extended barrel module will suffer from the energy leakage on the top.

• Proposal 2: A modification of this proposal with the addition of the two 1m prototypes on top in order to recover from the energy leakage from the top ext. barrrel module.

The problem now is that the weight is totally off-center and we are close to the limit for the operation of the jacks. I've spoken with the CERN engineers and they wouln'd be in favour of such a solution.

• Proposal 3: In order to improve the second proposal a new configuration was worked out which is basically the same but with the two exteneded barrel modules and the two old ones shifted towards the table center

3d view (beam left is to the left of the picture)	2d view

The exact dimensions of the module installation can be found in ( figure ).

With this solution the problem with the weight being off-center is solved (not completely, but now we can compensate the small difference by puting an extra weight on the empty side of the table - far left). The CERN engineers believe that we can pass the security inspection. The only problem is to guarantee the stability of the two ext. barrel modules (not sliding in front) but a possible solution was proposed which they will work out in detail.

There are though few problems with this setup which need answers from the various sub-system experts:

• we might not be able to calibrate with the Cs source the two upper modules. One might say we don't care too much since we can put the numbers from last year, or even more one could imagine to calibrate them before. For example, we can put the extender machine in some favourate position such that the wire can go through, do the HV setting for those two modules and then put the extender machine in its final position (extreem right of the table as last year).
• we have a problem in extracting the drawers from the two modules, since the side of the table will be about 1m away from the module's end plate. To go around this one could imagine the use of a platform on top of the old module, but a careful study has to be made.

It is certainly true that these two problems and in particular the second one, (and perhaps others that we might have not seen so far), are rather important during the installation phase. But is also true that this configuration is rather advantageous from the quality of the physics data we can take and from the fact that we can compare in almost the same way the two modules and extract valuable results.

Electronics - Read-Out

Regardless the modules configuration, there is a proposal to ecquip 15 channels of the middle module with the new bi-gain/12bit ADC readout. The actual electronics are in production these days, the first test bench results look rather promising and the people who are working on this are confident that they can meet the dates to have them installed from the beginning of the period.

The proposal was to ecquip 3 full consecutive towers:

1. A12,A13,A14,B11,B12,B13,D6 = 14 PMTs, or
2. A14,A15,A16,B13,B14,B15,D7 = 14 PMTs