The secondary beam diagnostics at the ACCULINNA-2 fragment separator is implemented event-by-event by the beam particle detector, allowing one to identify the projectile ion with the dE-ToF method ...and determine the ion’s velocity vector and localization on the target. The detector comprises two ToF stations and a pair of MWPCs. Two identical ToF stations located on the straight section of the ACCULINNA-2 fragment separator form a base of 12.35 m. In each station, light from a thin organic scintillator is detected with four compact PMTs directed symmetrically inside a closed volume. MWPCs are stationary shells designed to work in vacuum at atmospheric pressure of gas CF
4
. Each chamber provides
XY
coordinates with a pitch of 0.125 cm. This work studies the purpose and scope of application of the beam particles detector and its characteristics, layout, operation logic, as well as techniques of setting and calibration.
The proton and deuteron pickup reactions
and
were studied with the
radioactive beam produced by the new fragment separator ACCULINNA-2 at FLNR, JINR. These measurements were initially motivated as ...the test reactions intended for the elucidation of results obtained in the study of the extremely neutron-rich
H and
H systems created in the
and
reactions with the use of the same setup. In the
reaction the
Li ground-state (
) and its first excited state (2.69 MeV,
) were identified in the low-energy region of its excitation spectrum. The differential cross sections for the
population were extracted at the forward center-of-mass angles (
) and compared with the FRESCO calculations. Spectroscopic factor of
, derived by a model suggesting the
clustering was found in accord with the experimental data. The energy spectrum of
Li populated in the
reaction shows the strong peak which corresponds to the excitation of the second excited state of
Li (2.25 MeV,
). The fact that the ground and the first excited states of
Li were not observed in this reaction is consistent with the shell-model structure of the nuclei involved.
Setup fitting the requirements for the detailed study of the five-body decay of the
7
H nucleus obtained as a result of the proton transfer from the
8
He projectiles to the deuterium target nuclei is ...being built at the radioactive beam line of ACCULINNA-2 separator in the G.N. Flerov Laboratory of Nuclear Reactions. Described here is the assembly of 100 BC-404 plastic scintillators, intended for neutron detection, the annular Si detector telescope for the
3
He recoils, and the detector array providing the Δ
E
–
E
-TOF registration of
3
H nuclei emitted at the
7
H decay. Results obtained by the Monte Carlo simulations made for the energy values and flight passes of all these particles are given together with the luminosity expected for the discussed experiments.
Pulse shape discrimination is an important handle to improve sensitivity in low background experiments. A dedicated setup was built to investigate the response of high-purity germanium detectors to ...single Compton scattered events. Using properly collimated γ-ray sources, it is possible to select events with known interaction location. The aim is to correlate the position dependent signal shape with geometrical and electrical properties of the detector. We report on design and performance of the setup with a first look on data.
•Automatized setup for the signal characterization of a HPGe detector depending on interaction location and bias voltage.•Compton coincidence measurements with a Broad Energy Germanium (BEGe) detector.•Single site event selection with known interaction location and high purity.
NeuRad detector prototype pulse shape study Muzalevsky, I.; Chudoba, V.; Belogurov, S. ...
EPJ Web of Conferences,
01/2018, Letnik:
177
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
The EXPERT setup located at the Super-FRS facility, the part of the FAIR complex in Darmstadt, Germany, is intended for investigation of properties of light exotic nuclei. One of its modules, the ...high granularity neutron detector NeuRad assembled from a large number of the scintillating fiber is intended for registration of neutrons emitted by investigated nuclei in low-energy decays. Feasibility of the detector strongly depends on its timing properties defined by the spatial distribution of ionization, light propagation inside the fibers, light emission kinetics and transition time jitter in the multi-anode photomultiplier tube. The first attempt of understanding the pulse formation in the prototype of the NeuRad detector by comparing experimental results and Monte Carlo (MC) simulations is reported in this paper.
The CBM RICH project Adamczewski-Musch, J.; Becker, K.-H.; Belogurov, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2014, Letnik:
766
Journal Article
Recenzirano
The Compressed Baryonic Matter (CBM) experiment will study the properties of super dense nuclear matter by means of heavy ion collisions at the future FAIR facility. An integral detector component is ...a large Ring Imaging Cherenkov detector with CO sub(2) gas radiator, which will mainly serve for electron identification and pion suppression necessary to access rare dileptonic probes like e super(+)e super(-) decays of light vector mesons or J/ psi psi . We describe the design of this future RICH detector and focus on results obtained by building a CBM RICH detector prototype tested at CERN-PS.
A neutron spectrometer based on stilbene crystals has been developed by the Flerov Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research (Dubna, Russia). The timing resolution ...is determined as a function of the signal amplitude (σ
T
= 0.18 ns at an amplitude of 1 MeV in the electron equivalent). The measured energy resolution of the detecting modules for γ rays is σ
E
/
E
= 4.5% at
E
= 1 MeV. The quality of the
n
–γ discrimination is investigated. It is shown that reliable discrimination is possible, beginning with a deposited energy of 100 keV in the electron equivalent, which corresponds to the kinetic energy of recoil protons of ∼700 keV. The neutron spectrometer helps to significantly expand the experimental capabilities and to carry out correlation experiments with radioactive beams on the ACCULINNA-2 fragment separator at a new level of quality.
Due to conceptual difference between geometry descriptions in Computer-Aided Design (CAD) systems and particle transport Monte Carlo (MC) codes direct conversion of detector geometry in either ...direction is not feasible. The paper presents an update on functionality and application practice of the CATIA-GDML geometry builder first introduced at CHEP2010. This set of CATIAv5 tools has been developed for building a MC optimized GEANT4/ROOT compatible geometry based on the existing CAD model. The model can be exported via Geometry Description Markup Language (GDML). The builder allows also import and visualization of GEANT4/ROOT geometries in CATIA. The structure of a GDML file, including replicated volumes, volume assemblies and variables, is mapped into a part specification tree. A dedicated file template, a wide range of primitives, tools for measurement and implicit calculation of parameters, different types of multiple volume instantiation, mirroring, positioning and quality check have been implemented. Several use cases are discussed.
The one-neutron transfer
2
H(
9
Li,
p
)
10
Li reaction has been investigated at 29
A
MeV incident energy at the ACCULINNA-2 facility (Flerov Laboratory of Nuclear Reactions, Joint Institute for ...Nuclear Research). The setup has been used in order to detect the recoil protons at backward angles in coincidences with the outgoing
9
Li and neutrons from the
10
Li decay at forward angles. This setup allows to study the
10
Li emitted in the crucial region at forward angles in the center of mass. The preliminary results in the part of the analysis of double proton–
9
Li coincidence are reported.
Event reconstruction in the RICH detector of the CBM experiment at FAIR Adamczewski, J.; Becker, K.-H.; Belogurov, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2014, Letnik:
766
Journal Article
Recenzirano
The Compressed Baryonic Matter (CBM) experiment at the future FAIR facility will investigate the QCD phase diagram at high net-baryon densities and moderate temperatures. One of the key signatures ...will be di-leptons emitted from the hot and dense phase in heavy-ion collisions. Measuring di-electrons, a high purity of identified electrons is required in order to suppress the background. Electron identification in CBM will be performed by a Ring Imaging Cherenkov (RICH) detector and Transition Radiation Detectors (TRD). In order to access the foreseen rare probes, the detector and the data acquisition have to handle interaction rates up to 10 MHz. Therefore, the development of fast and efficient event reconstruction algorithms is an important and challenging task in CBM. In this contribution event reconstruction and electron identification algorithms in the RICH detector are presented. So far they have been developed on simulated data but could already be tested on real data from a RICH prototype testbeam experiment at the CERN-PS. Efficient and fast ring recognition algorithms in the CBM-RICH are based on the Hough Transform method. Due to optical distortions of the rings, an ellipse fitting algorithm was elaborated to improve the ring radius resolution. An efficient algorithm based on the Artificial Neural Network was implemented for electron identification in RICH. All algorithms were significantly optimized to achieve maximum speed and minimum memory consumption.
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