The H7 system was populated in the H2(He8,He3)H7 reaction with a 26 AMeV He8 beam. The H7 missing mass energy spectrum, the H3 energy and angular distributions in the H7 decay frame were ...reconstructed. The H7 missing mass spectrum shows a peak, which can be interpreted either as unresolved 5/2+ and 3/2+ doublet or one of these states at 6.5(5) MeV. The data also provide indications of the 1/2+ ground state of H7 located at 1.8(5) MeV with quite a low population cross section of ∼25 μb/sr within angular range θc.m.≃(17°-27°).
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.
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.
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.
The commissioning of the new fragment separator ACCULINNA-2 at FLNR JINR is accomplished. The separator is destined to expand the possibilities in studies of dripline nuclei performed with the exotic ...secondary radioactive ion beams (RIBs) at energies of (5 - 50) AMeV. The projected high transmission and purification level were confirmed experimentally for a number of RIBs in the last two years. The ACCULINNA-2 setup will become a backbone facility at FLNR for the research in the field of light exotic nuclei. This report shows the current status of the separator, describes the obtained RIBs parameters and first experiments as well, provides the overview of the developing detection, monitoring and control subsystems.
The articled focused on the pharmacoinvasive approach to the treatment of acute ST-segment elevation myocardial infarction. Current guidelines prioritize the primary transcutaneous coronary ...intervention. However, in both the Russian Federation and other countries, there are some peculiarities (logistic issues, specific aspects of infrastructure of medical facilities), which may hamper timely conduction of the endovascular treatment. In such cases, the thrombolytic therapy subsequently supplemented with transcutaneous coronary intervention would appear the most effective strategy aimed at the earliest recovery of coronary perfusion. The authors provided results of major studies that used such approach and the effect of using the thrombolytic therapy with recombinant prourokinase, a Russian third generation thrombolytic drug.
The extremely neutron-rich systems 7H, 6H were studied in the 2H(8He, 3He)7H and 2H(8He, 4He)6H proton and deuteron pickup reactions with a 26 AMeV secondary 8He beam produced at the new ACCULINNA-2 ...fragment separator. In addition, the same proton and deuteron pickup reactions were generated using the 42 AMeV 10Be beam, and the population of low-lying 9Li and 8Li states was measured in reactions 2H(10Be,3He)9Li and 2H(10Be,4He)8Li, respectively. The latter were used as reference measurements in order to check the setup calibration over the excitation energy of 7,6H and to determine the real experimental energy resolution which was compared with Monte Carlo calculations. The corresponding results obtained for the superheavy hydrogen systems 7H, 6H are presented and discussed. Typical excitation spectra of the 9Li and 8Li nuclei are also shown.
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.
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.
PDF
