A. Rogachevskiy

Dual magnetic separator for TRI mu P

The TRIμPTRIμP facility, under construction at KVI, requires the production and separation of short-lived and rare isotopes. Direct reactions, fragmentation and fusion–evaporation reactions in normal and inverse kinematics are foreseen to produce nuclides of interest with a variety of heavy-ion beams from the superconducting cyclotron AGOR. For this purpose, we have designed, constructed and commissioned a versatile magnetic separator that allows efficient injection into an ion catcher, i.e., gas-filled stopper/cooler or thermal ionizer, from which a low energy radioactive beam will be extracted. The separator performance was tested with the production and clean separation of 21Na ions, where a beam purity of 99.5% could be achieved. For fusion–evaporation products, some of the features of its operation as a gas-filled recoil separator were tested.

Production of radioactive nuclides in inverse reaction kinematics

Efficient production of short-lived radioactive isotopes in inverse reaction kinematics is an important technique for various applications. It is particularly relevant when the isotope of interest is only a few nucleons away from a stable isotope. In this article production via charge exchange and stripping reactions in combination with a magnetic separator is explored. The relation between the separator transmission efficiency, the production yield, and the choice of beam energy is discussed. The results of some exploratory experiments will be presented.

Dual magnetic separator for TRIμPTRIμP

The TRIμPTRIμP facility, under construction at KVI, requires the production and separation of short-lived and rare isotopes. Direct reactions, fragmentation and fusion–evaporation reactions in normal and inverse kinematics are foreseen to produce nuclides of interest with a variety of heavy-ion beams from the superconducting cyclotron AGOR. For this purpose, we have designed, constructed and commissioned a versatile magnetic separator that allows efficient injection into an ion catcher, i.e., gas-filled stopper/cooler or thermal ionizer, from which a low energy radioactive beam will be extracted. The separator performance was tested with the production and clean separation of 21Na ions, where a beam purity of 99.5% could be achieved. For fusion–evaporation products, some of the features of its operation as a gas-filled recoil separator were tested.

TRI mu P - A radioactive isotope trapping facility at KVI

Abstract TRIμP, a new research facility to produce and trap rare and short-lived isotopes for high precision physics experiments is under design and construction at KVI. This facility makes use of the existing super-conducting cyclotron and the infrastructure of the laboratory. To be able to study a large variety of heavy ions a new dual function magnetic separator has been developed. Details of the separator and the status of the project will be presented.

Aspects of Cooling at the TRI{mu}P Facility

The TriμP facility at KVI is dedicated to provide short lived radioactive isotopes at low kinetic energies to users. It comprised different cooling schemes for a variety of energy ranges, from GeV down to the neV scale. The isotopes are produced using beam of the AGOR cyclotron at KVI. They are separated from the primary beam by a magnetic separator. A crucial part of such a facility is the ability to stop and extract isotopes into a low energy beamline which guides them to the experiment. In particular we are investigating stopping in matter and buffer gases. After the extraction the isotopes can be stored in neutral atoms or ion traps for experiments. Our research includes precision studies of nuclear β‐decay through β‐ν momentum correlations as well as searches for permanent electric dipole moments in heavy atomic systems like radium. Such experiments offer a large potential for discovering new physics.

TRIμP — trapped radioactive isotopes: μicrolaboratories for fundamental physics

Abstract At the Kernfysisch Versneller Instituut (KVI) a new facility (TRIμP) is under development. It aims for producing a spectrum of radioactive isotopes in direct, inverse kiematics fusion and evaporation or fragmentation reactions with heavy ion beams from the superconducting cyclotron AGOR. The products will be slowed down and trapped for accurate measurements of fundamental symmetries and interactions in physics. The scientific focus of the local KVI research groups includes precision studies of nuclear β-decays through β-neutrino (recoil nucleus) momentum correlations in weak decays and searches for permanent electric dipole moments in heavy atomic systems. This research programme offers a large potential for discovering new physics or to limit parameters in models beyond standard theory significantly. The scientific approach chosen in TRIμP can be regarded as complementary to such high energy physics. The TRIμP facility in Groningen will be open for users worldwide.

R-matrix analysis of the {beta} decays of {sup 12}N and {sup 12}B

The beta decays of N-12 and B-12 have been studied at KVI and JYFL to resolve the composition of the broad and interfering 0(+) and 2(+) strengths in the triple-alpha continuum. For the first time a complete treatment of 3 alpha decay is presented including all major breakup channels. A multilevel, many-channel R-matrix formalism has been developed for the complete description of the breakup in combination with the recently published separate analysis of angular correlations. We find that, in addition to the Hoyle state at 7.65 MeV, more than one 0(+) and 2(+) state is needed to reproduce the spectra. Broad 0(3)(+) and 2(2)(+) states are found between 10.5 and 12 MeV in this work. The presence of beta strength up to the N-12 Q-value window suggests the presence of additional 0(+) and 2(+) components in the C-12 structure at energies above 12.7 MeV.

The beta-gamma decay of Na-21

A new and independent determination of the Gamow-Teller branching ratio in the beta-decay of 21Na is reported. The value obtained of 5.13 +- 0.43 % is in agreement with the currently adopted value and the most recent measurement. In contrast to previous experiments, the present method was based on the counting of the parent 21Na ions and the resulting 351 keV gamma-rays without coincident beta-particle detection.A new and independent determination of the Gamow–Teller branching ratio in the β-decay of 21Na is reported. The value 5.13 ± 0.43% obtained is in agreement with the currently adopted value and the most recent measurement. In contrast to previous experiments, the present method was based on the counting of the parent 21Na ions and the resulting 351 keV γ-rays without coincident β-particle detection.

STUDIES OF C-12 USING beta-DECAYS

The nuclear structure of states in C-12 have been a subject of interest for both theory and experiment since the early days of nuclear physics. Many open questions remain, especially concerning the existence and properties of 0(+) and 2(+) states in the triple alpha continuum. A series of experiments have been performed using beta-decay of N-12 and B-12 to probe these states. The latest experiment was performed at KVI using an implantation method, measuring the sum energy of the three alpha-particles directly. Preliminary results from this experiment will be presented.

Dual magnetic separator for

The TRIμPTRIμP facility, under construction at KVI, requires the production and separation of short-lived and rare isotopes. Direct reactions, fragmentation and fusion–evaporation reactions in normal and inverse kinematics are foreseen to produce nuclides of interest with a variety of heavy-ion beams from the superconducting cyclotron AGOR. For this purpose, we have designed, constructed and commissioned a versatile magnetic separator that allows efficient injection into an ion catcher, i.e., gas-filled stopper/cooler or thermal ionizer, from which a low energy radioactive beam will be extracted. The separator performance was tested with the production and clean separation of 21Na ions, where a beam purity of 99.5% could be achieved. For fusion–evaporation products, some of the features of its operation as a gas-filled recoil separator were tested.