Experiment Proposal - opera - Infn

The general MTS approach is hardware-independent; therefore, it is possible to closely follow the
technological evolution without changing the basic framework. The goal is to increase by one to two
orders of magnitude the present scanning speed. Among the areas in which substantial upgrades can be
obtained in a medium term period we quote
• a new tracking method, essentially in the two horizontal dimensions, by superposing all the fields
of view of one emulsion layer; the reconstruction in space is performed at the end;
• a custom frame grabbing device, based on new commercial CMOS sensors, is being studied; it is a
megapixel sensor, capable of operating at a tunable frame rate, up to 500 Hz; the amount of data
(500 Mbyte/s) is difficult to handle by presently available frame grabbers; a dedicated electronic
architecture is being studied;
• a new, specially designed stage, capable of moving and stopping without appreciable oscillations
at the foreseen high scanning rates;
• a new wide field optics (for instance, a diameter of 400 µm of more) with good image quality;
• an automatic device to replace and set the emulsion films into position on the microscope stage,
without the need of human intervention.
The solution of the problems related to each of the above points could lead to an increase of the
overall scanning speed by a factor between two and ten with respect to the presently achieved values.
Therefore the total gain between one and two orders of magnitude looks possible. Special care will be
devoted to the data acquisition and handling (including a general database). In fact, due to the large
quantity of data (both as input and output) any problem could have serious effects.
9.2.3 Future test beam measurements
In the coming years, the OPERA collaboration will continue to need test beams and floor space at CERN
for prototype testing and studies on ECC bricks and electronic trackers.
The dimensions of the electronic detectors require a rather large floor space. The former CHARM II
building seems to be suitable. The muon rates from the SPS West Area test beams are low. However, if
the beam time is not limited this does not constitute a problem. In addition, a floor space in a hall of
about 200 m 2 with a height of 10 m is required for assembly tests of prototypes detectors.
The experience gained with the latest test beam periods has shown that both the X5 and X7 beams
are suitable for studies of the brick response to electrons and muons. The beam features are well known
and excellent particle identification and rate monitoring are available. Exposures with as few as 100
particles over the whole brick surface have been achieved. These beams are well suited for several short
tests distributed over the year. For test experiments in which specific trigger conditions and extensive
control of the beam line are needed, we plan to use the T7 or the T9 beam in the PS East Hall.
As tentative scheme, in the forthcoming two years we will require the present setup in the CHARM II
building as a permanent test facility, several short periods per year in the X5 and/or X7 beams for specific
measurements of emulsion films and about one month running time per year in the PS T7 and/or T9
beam lines.
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