References - Bogoliubov Laboratory of Theoretical Physics - JINR

framework with the use of deuteron wave function (DWF), derived from the dressed bag
model of Moscow-Tuebingen group [7]. Dash-dotted curves conform to the calculations
performed within the multiple scattering expansion formalism with the use of CD-Bonn
DWF [8]. The parameterization of the NN t-matrix [9] has been used to take the offshell
effects into account. The deviation of the data from the calculations can indicate
the sensitivity to the short-range 3N correlations.
The dp breakup reaction will be investigated using ΔE-E techniques for the detection
of protons. 8 detectors of this kind are planned to use in the experiment. Each detector
consists of two scintillators ΔE and E.
The first scintillator has the cylindrical shape with
the height 10 mm and the diameter 100 mm. Two
PMTs-85 view the scintillator and they are located the
friend opposite to the friend. Two planes have been
made on the scintillator to increase the area of the optical
contact between the scintillator and photocatode
of the PMT-85. These planes have been polished (see
Fig.3). ΔE scintillator it is covered by a white paper.
Digital dividers of voltage are used for PMT-85.
Figure 3: The schematic view
of the ΔE-E detector for dp ��ã
breakup reaction study.
E scintillator also has the cylindrical form with the height 200 mm and diameter 100
mm. PMT-63 view through this scintillator. Given PMT has been chosen because of the
suitable size of the cathode (100 mm) with both good time and amplitude properties.
E scintillator has been wrapped by a white paper. The part which is located to ΔE
scintillator has been covered by a black paper. It is made to exclude possibility of the
light hit from one plastic scintillator to another.
The beam test of two ΔE-E detectors at ITS has
been performed at the initial deuteron kinetic energy of
2.3 GeV in June 2008. During this test a new DAQsystem
based on the trigger LT320D module has been
used. One of the important advantages of this module
is the possibility to control the status of majority coincidence
circuit on-line. The trigger used was the coincidence
of the signals from 2 ΔE-E detectors located in
the horizontal plane on the left and right from the initial
beam direction.
First results for the beam test of ΔE-E counters are
presented in Fig.4. The results on the correlation of the
energy depositions in two E- scintillation counters and
their time-of-flight difference are given in Fig.4.
The modernization of ΔE-E detectors consists in the
diminution of the ΔE scintillator diameter to 8 cm. It
has allowed to reduce the solid angle for detected nu-
Figure 4: The correlation of amplitudes
from two E-detectors and
their time-of-flight difference.
cleons. Solid angle reduction allows to exclude nucleons which take off through a E -
scintillator lateral side. This detector was tested with cosmic muons. Results of the calibration
are presented on Fig.5. Pedestal is disposed in 23-rd bin. Mean size of amplitude
distribution from E - scintillator is equal to 243 channels. 10 channels are equal 1.8 MeV
for this configuration of the detector.
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