R.S. Slepnev 1, A.V. Daniel 1, M.S. Golovkov 1, V. Chudoba 1,2, A.S.
Fomichev 1, A.V. Gorshkov 1, V.A. Gorshkov 1, S.A. Krupko 1, G.
Kaminski 1,3, A.S. Martianov 1, S.I. Sidorchuk 1 and A.A. Bezbakh 1
1 – Flerov Laboratory of Nuclear Reaction Joint Institute for
Nuclear Research, Dubna Russia
2 – Institute of Physics, Silesian University in Opava, Bezrucovo
nam. 13, 74601 Czech Republic
3 – Institute of Nuclear Physics PAN, Radzikowskiego 152, PL-31342
Krakow, Poland
Introduction
In order to study light proton and neutron rich nuclei close to drip line, the physics
programs for the ACCULINNA facility and the future ACCULINNA-2 facility require a
relevant data acquisition system (DAQ). Such a system should satisfy several
conditions: it should have low price per channel, ability to process a high trigger rate
with a low ‘dead time’, and in addition it should be scalable and flexible.
VME based data acquisition system
Detectors
Preamplifiers
Amplifiers &
Discriminators
DAQ in this scheme includes various electronic modules,
computers and the related software. To save time, we decided
to take existing DAQ from GSI as the architectural prototype.
The DAQ is based on VME and CAMAC modules, real time
Operating System LynxOS and MBS software, combined with Go4
software based on ROOT data analysis framework for visualization
of the information coming from the detectors.
DAQ
Software
The screen with data output of Go4 software is
shown. The top row reflects data from TOF plastics
(two matrix of Left Amplitude vs. Right Amplitude
and DE-TOF spectrum), the bottom row shows
beam spot on the target in both directions (data
from MWPC’s).
In order to use MBS program and see
information from VME and CAMAC
modules one should have functions in C
language for each type of module and
write user function as main program
where described procedure of
initializing, readout, etc. Thereto the C
code obtained should be compiled in
LynxOS running on RIO-3 VME module
that is booting by network from the
external computer working on Scientific
Linux. If everything were made right one
can start the MBS program in LynxOS,
which we generally used to read out
VME and CAMAC modules. After that,
data acquisition should be started from
this program. To see the events coming
from the detectors in graphics online, we
used Go4 software.
New possibilities
Typical identification plot ‘Energy loss in 68 mkm
silicon vs. TOF’ when ACCULINNA facility was tuned
for the maximal yield of 18Ne nuclei (contamination
of unwanted nuclei in the focal plane F4 was ~75%).
26S
By this experiment it was shown, that thereby we can work now on the ACCULINNA facility with RIBs (generally
proton rich) when in the beam there is only a very small percent of nuclei that we want to obtain and utilization of the
detectors, electronics and DAQ is very large. In the future we are planning to use advantages of new DAQ by starting
working with new VME modules – registers, digitizers, etc. In addition we can plug in to our DAQ the crates in other
standards (Fastbus, VXI) which give us possibility to use for example detectors and electronics for registering discrete
gamma rays. Since the data files from DAQ can be easily converted to ROOT format one can use this framework to analyze
the experimental data. Thus, thereby we have got working DAQ that meets to modern experimental requirements in heavy
ion physics.
Conclusion
We have studied and applied new data acquisition system. The existing
software (Go4 v.4.4.3) was upgraded on 64 digit platform and several new user
functions were developed (Mesytec MADC-32, CAEN V775NC). The performed
work allows us to conduct some experiments on the world level by now those
were unavailable earlier for us.