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Recapturing the recoiling daughters from radioactive decay can be a simple way to diversify beam availability at rare isotope beam facilities. In the decay and recapture ion trapping (DRIT) technique, a parent species is stored in an ion trap and left to decay, and the daughter ions are recaptured by the trap and become available for use. We successfully demonstrated the technique using the electron beam ion trap (EBIT) at the TITAN facility. A pure cloud of 30Mg ions was stored in the EBIT for about one half-life and sent to a Penning trap mass spectrometer, which confirmed the production of 30Al daughter ions. Systematic measurements and simulations suggest high recapture efficiencies of the recoil ion and little influence of the recoiling energy in the observed losses. With the secondary beam, we also performed precision mass measurements of the parent 30Mg8+ and the daughter 30Al11+ ions. Our results agree with the literature and improve its precision. The success of this experiment shows that EBITs can produce high-quality beams through the DRIT technique. [ABSTRACT FROM AUTHOR]

High-precision and accurate atomic mass measurements are vital for the description of nuclear structure, investigations of nuclear astrophysical processes, and tests of fundamental symmetries. We report on mass measurements of short-lived highly charged ions using the TITAN Penning-trap mass spectrometer at TRIUMF. To increase the overall efficiency and precision of the mass measurement of highly charged ions, an addition to the TITAN system, the novel cooler Penning trap CPET is discussed. [ABSTRACT FROM AUTHOR]

The introduction of Paul traps, in particular linear radio-frequency quadrupoles in the early 2000s, has revolutionized the use of ion traps for probing the properties of radioactive nuclides. It opened the path to trapping all available nuclides, independent of their chemical properties. We present an overview of direct mass measurements of short-lived nuclides using TITAN, a Penning trap mass spectrometer facility particularly suitable for precision measurements of ms-half-life nuclides. [ABSTRACT FROM AUTHOR]

TITAN is an on-line facility dedicated to precision experiments with short-lived radioactive isotopes, in particular mass measurements. The achievable resolution on mass measurement, which depends on the excitation time, is limited by the half life of the radioactive ion. One way to bypass this is by increasing the charge state of the ion of interest. TITAN has the unique capability of charge-breeding radioactive ions using an electron-beam ion trap (EBIT) in combination with Penning trap mass spectrometry. However, the breeding process leads to an increase in energy spread, Δ E, which in turn negatively influences the mass uncertainty. We report on the development of a cooler Penning trap which aims at reducing the energy spread of the highly charged ions prior to injection into the precision mass measurement trap. Electron and proton cooling will be tested as possible routes. Mass selective cooling techniques are also envisioned. [ABSTRACT FROM AUTHOR]

The precision of atomic mass measurements in a Penning trap is directly proportional to the charge state q of the ion and, hence, can be increased by using highly charged ions (HCI). For this reason, charge breeding with an electron beam ion trap (EBIT) is employed at TRIUMF’s Ion Trap for Atomic and Nuclear science (TITAN) on-line facility in Vancouver, Canada. By bombarding the injected and trapped singly charged ions with an intense beam of electrons, the charge state of the ions is rapidly increased inside the EBIT. To be compatible with the on-line requirements of short-lived isotopes, very high electron beam current densities are needed. The TITAN EBIT includes a 6 Tesla superconducting magnet and is designed to have electron beam currents and energies of up to 5 A and 60 keV, respectively. Once operational at full capacity, most species can be bred into a He-like configuration within tens of ms. Subsequently, the HCI are extracted, pass a Wien filter to reduce isobaric contamination, are cooled, and injected into a precision Penning trap for mass measurement. We will present the first results and current status of the TITAN EBIT, which has recently been moved to TRIUMF after assembly and commissioning at the Max-Planck-Institute (MPI) for Nuclear Physics in Heidelberg, Germany. [ABSTRACT FROM AUTHOR]

The TITAN facility at TRIUMF-ISAC will use four ion traps with the primary goal of determining nuclear masses with high precision, particularly for short lived isotopes with lifetimes down to approximately 10 ms. The design value for the accuracy of the mass measurement is 1 ×10 − 8. The four main components in the facility are an RF cooler/buncher (RFCT) receiving the incoming ion beam, an electron beam ion trap (EBIT) to breed the ions to higher charge states, a cooler Penning trap (CPET) to cool the highly charged ions, and finally the measurement Penning trap (MPET) for the precision mass determination. Additional goals for this system are laser spectroscopy on ions extracted from the RFCT and beta spectroscopy in the EBIT (in Penning trap mode) on ions that are purified using selective buffer gas cooling in the CPET. The physics motivation for the mass measurements are manifold, from unitarity tests of the CKM matrix to nuclear structure very far from the valley of stability, nuclear astrophysics and the study of halo-nuclei. As a first measurement the mass of 11Li will be determined. With a lifetime of 8.7 ms and a demonstrated production rate of 4×104 ions/sec at ISAC the goal for this measurement at TITAN is a relative uncertainty of 5×10 − 8. This would check previous conflicting measurements and provide information for nuclear theory and models. [ABSTRACT FROM AUTHOR]

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The TITAN facility at TRIUMF is a series of ion traps designed for precision mass spectrometry on rare isotopes. The combination of an on-line electron beam ion trap charge breeder with a Penning trap enables measurements with radioactive ions in high charge states. The use of highly charged ions (HCI) can yield a significant gain in mass precision and mass resolving power. However, the benefits of high charge states are mitigated since the charge breeding deteriorates the beam quality. To achieve suitable beam properties and access the full potential of Penning trap mass spectrometry with HCI a cooler Penning trap (CPET) for electron cooling of highly charged radioisotopes is being developed. In this device short-lived HCI will be sympathetically cooled by a co-trapped electron plasma prior to mass measurement. For electron plasma generation electrons are injected from an off-axis electron gun placed in the fringe field of CPET's solenoid magnet. We report on the development of an electron gun design that is adapted to the operation in lateral magnetic fields and has enabled efficient and robust electron plasma formation in CPET. [ABSTRACT FROM AUTHOR]

The transition probability of the magnetic dipole (M1) transition 2s22p 2Po J=1/2 to J′=3/2 (λ=574.19 nm) in the B-like ion Cl12+ has been measured using two different light sources, the Heidelberg heavy-ion storage ring TSR and the Livermore electron beam ion trap EBIT-I. Our results for the atomic level lifetime are (21.2±0.6) ms from the heavy-ion storage ring and (21.0±0.5) ms from the electron beam ion trap. Particular attention has been paid to systematic errors, using these measurements as well as recent measurements on Fe10+ and Fe13+ ions as examples. [Copyright &y& Elsevier]

The performance of high-precision mass spectrometry of radioactive isotopes can often be hindered by large amounts of contamination, including molecular species, stemming from the production of the radioactive beam. In this paper, we report on the development of Collision-Induced Dissociation (CID) as a means of background reduction for experiments at TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). This study was conducted to characterize the quality and purity of radioactive ion beams and the reduction of molecular contaminants to allow for mass measurements of radioactive isotopes to be done further from nuclear stability. This is the first demonstration of CID at an ISOL-type radioactive ion beam facility, and it is shown that molecular contamination can be reduced up to an order of magnitude. [Display omitted] • Radioactive ion beams contain high levels of background which obscure measurements. • Collision induced dissociation can reduce molecular contamination. • An MR-TOF-MS offers both broadband and high resolution mass spectrometry. • An MR-TOF-MS in an ideal device for beam composition tests. • A push further from nuclear stability is now possible at TITAN. [ABSTRACT FROM AUTHOR]

Mass measurements continue to provide invaluable information for elucidating nuclear structure and scenarios of astrophysical interest. The transition region between the Z = 20 and 28 proton shell closures is particularly interesting due to the onset and evolution of nuclear deformation as nuclei become more neutron-rich. This provides a critical testing ground for emerging ab-initio nuclear structure models. Here, we present high-precision mass measurements of neutron-rich chromium isotopes using the sensitive electrostatic Multiple-Reflection Time-Of-Flight Mass Spectrometer (MR-TOF-MS) at TRIUMF's Ion Trap for Atomic and Nuclear Science (TITAN) facility. Our high-precision mass measurements of 59,61−63Cr confirm previous results, and the improved precision in measurements of 64−65Cr refine the mass surface beyond N=40. With the ab initio in-medium similarity renormalization group, we examine the trends in collectivity in chromium isotopes and give a complete picture of the N=40 island of inversion from calcium to nickel. [ABSTRACT FROM AUTHOR]

A measurement of the a-ß-? angular correlation in the Gamow-Teller decay 8Li→8Be* + ? + ß, 8Be*→a + a has been performed using ions confined in a linear Paul trap surrounded by silicon detectors. The energy difference spectrum of the a particles emitted along and opposite the direction of the ß particle is consistent with the standard model prediction and places a limit of 3.1% (95.5% confidence level) on any tensor contribution to the decay. From this result, the amplitude of any tensor component CT relative to that of the dominant axial-vector component CA of the electroweak interaction is limited to |CT/CA|<0.18 (95.5% confidence level). This experimental approach is facilitated by several favorable features of the 8Li ß decay and has different systematic effects than the previous ß-? correlation results for a pure Gamow-Teller transition obtained from studying 6He ß decay. [ABSTRACT FROM AUTHOR]

The use of highly charged ions increases the precision and resolving power, in particular for short-lived species produced at on-line radio-isotope beam facilities, achievable with Penning trap mass spectrometers. This increase in resolving power provides a new and unique access to resolving low-lying long-lived (T1/2 > 50 ms) nuclear isomers. Recently, the 111.19(22) keV (determined from γ-ray spectroscopy) isomeric state in 78Rb was resolved from the ground state, in a charge state of q = 8+ with the TRIUMF Ion Trap for Atomic and Nuclear science at the TRIUMF's Isotope Separator and Accelerator facility. The excitation energy of the isomer was measured to be 108.7(6.4) keV above the ground state. The extracted masses for both the ground and isomeric states, and their difference, agree with the AME2003 and Nuclear Data Sheet values. This proof of principle measurement demonstrates the feasibility of using Penning trap mass spectrometers coupled to charge breeders to study nuclear isomers and opens a new route for isomer searches. [ABSTRACT FROM AUTHOR]