| High
Energy Site |
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Experimental
Site
The initial proton beam for PIF is delivered from
the PROSCAN accelerator with
the help of the primary energy degrader, which allows to set the initial beam energy
from 250 MeV down to 70 MeV. The beam is subsequently guided to the Experimental
Area where PIF facility is located.
Having energy of the beam degraded directly after accelerator exit causes also
its intensity reduction on target.
Additional safety reasons put the maximum beam intensity in the PIF area up to
2 nA for energies above 200 MeV, 5 nA for energies from 100 MeV to 200 MeV and
10 nA for energies below 100 MeV.
As PROSCAN accelerator serves also two GANTRY stations
and OPTIS2 facility for cancer treatment, most of PIF exposures are conducted
during weekends and nighshifts.
The PIF experimental set-up consists of the
local PIF energy degrader, beam collimating
and monitoring devices (Photo 1).
Photo 1. PIF-PROSCAN downstream view with
ionization chamber, energy degrader and wire chamber.
Movable XY table with the sample holder (see Photo 2)
enables easy mounting of the
user's device under test (DUT) on the beam.
Photo 2. PIF-NA3 rear view of the XY-table
with movable arm and sample holder.
The laser mounted downstream from the XY table allows to
center the DUT and control
its position (see Photo 3).
Photo 3. PIF-NA3 Side view with the
laser for sample centering and beam dump.
The door of the beam dump are closed during the test setup to protect
people against
radioactivity coming from the beam dump.
Irradiations are usually carried out in air. The maximum
allowed energy is 254 MeV and the
maximum current is limited to about 1 nA due to air activation in the
experimental area.
According to
experience and user requirements, the monitor detectors are
selected for each
experiment individually: ionization chambers,
Si-detectors, plastic scintillators. Schematic view
of the
experimental set-up is shown in Figure below:
Figure 1. PIF-NA3 Experimental
site (not in scale).
The irradiation is controlled
through a set of scalers and a PC-based data acquisition system.
The system monitors proton flux and dose rate, calculates the total deposited
dose and
controls the position of the sample as well as beam focus
parameters. It also allows for
setting the beam energy with the
help of the PIF local energy degrader. This makes it
possible
to perform fully
automated irradiations with arbitrary proton spectra.
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Initial proton energies: 254, 102 and 60 MeV
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Energies available using the PIF
degrader:
quasi continuously from 35 (6) MeV up to 254 (60) MeV
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Energy straggling for the 300 MeV
initial beam beam:
e.g. FWHM=7.2 MeV at 200.0 MeV, FWHM=15.4 MeV at 50.0
MeV.
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The maximum beam intensity at
254 MeV: 1 nA
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The maximum flux at 254 MeV with 10 mA
split beam (focused beam):
2.5*108 protons/sec/cm2
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Beam profiles are either flat
or Gaussian-form
with minimum FWHM=6 cm
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Irradiations take place in air
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The maximum diameter of the irradiated
area: f 9 cm
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The accuracy of the flux/dose
determination: 5%
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Neutron background: less than 10-4
neutrons/proton/cm2
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Irradiations, devices and
sample positioning are supervised by the computer
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Sample mounting frame 25 x 25 cm2 (SEU and HIF
facilities compatible)
is attached to the XY table
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Data acquisition system allows
automatic runs with user pre-defined
irradiation criteria
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