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The Superallowed Transition Beta-Neutrino Decay Ion Coincidence Trap (St. Benedict) is currently under construction at the University of Notre Dame Nuclear Science Laboratory. It is designed to measure the beta-neutrino angular correlation parameter in superallowed mixed beta-decay transitions between mirror nuclei in order to extract the Fermi-to-Gamow Teller mixing ratio and test theoretical corrections entering in the determination of the V u d element of the Cabibbo–Kobayashi–Maskawa quark mixing matrix. St. Benedict includes a large volume gas catcher to thermalize the radioactive ion beam from TwinSol , a differentially-pumped extraction system, a radiofrequency quadrupole ion cooler and buncher, and a Paul trap for the observation and detection of the β decay products. The status of each of these components will be presented. [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]

Abstract.: A new technique has been developed at the TRIUMF’s TITAN facility to perform in-trap decay spectroscopy. The aim of this technique is to eventually measure weak electron capture branching ratios (ECBRs) and by this to consequently determine GT matrix elements of $ \beta$ $ \beta$ decaying nuclei. These branching ratios provide important input to the theoretical description of these decays. The feasibility and power of the technique is demonstrated by measuring the ECBR of 124Cs . [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]

TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN) constitutes the only high precision mass measurement setup coupled to a rare isotope facility capable of increasing the charge state of short-lived nuclides prior to the actual mass determination in a Penning trap. Recent developments around TITAN's charge breeder, the electron beam ion trap, form the basis for several successful experiments on radioactive isotopes with half-lives as low as 65 ms and in charge states as high as 22+. [ABSTRACT FROM AUTHOR]

Precise atomic mass determinations play a key role in various fields of physics, including nuclear physics, testing of fundamental symmetries and constants and atomic physics. Recently, the TITAN Penning trap measured the masses of several neutron halos. These exotic systems have an extended, diluted, matter distribution that can be modelled by considering a nuclear core surrounded by a halo formed by one or more of loosely bound neutrons. Combined with laser spectroscopy measurements of isotopic shifts precise masses can be used to obtain reliable charge radii and two-neutron-seperation energies for these halo nuclei. It is shown that these results can be used as stringent tests of nuclear models and potentials providing an important metric for our understanding of the interactions in all nuclei. [ABSTRACT FROM AUTHOR]

Knowledge of 2 νββ nuclear matrix elements is essential to probe the theoretical framework of 0 νββ decays. At TITAN, TRIUMF's Ion Trap for Atomic and Nuclear science, a novel technique has been developed to measure electron capture branches of virtual intermediate nuclei in ββ decays. During two experiments with radioactive Cs isotopes the feasibility of this new method was proven. [ABSTRACT FROM AUTHOR]

Abstract: TITAN (TRIUMF''s Ion Traps for Atomic and Nuclear science) is a novel online facility for high-precision mass measurements on short-lived isotopes. TITAN is the only such facility that employs an Electron-Beam Ion Trap (EBIT) charge-state breeder to produce highly charged ions for their use to increase the precision of mass measurements. We describe the recently commissioned TITAN EBIT and present the results of first injection, charge breeding, and extraction tests performed with stable and radioactive ions. [Copyright &y& Elsevier]

Thanks to extensive experimental efforts that led to a precise determination of the various superallowed 0 + → 0 + pure Fermi transition experimental quantities, we now have a very precise value for V ud that leads to a stringent test of the CKM matrix unitarity. Despite this achievement, measurements in other less precise systems remain relevant as conflicting results could uncover unknown systematic effects or even new physics. One such system is the superallowed mixed transition, which can help refine the same theoretical corrections used for pure Fermi transitions and hence improve the accuracy of V ud . However, as a corrected F t -value determination from these systems requires the more challenging determination of the Fermi Gamow–Teller mixing ratio, only five transitions, spreading from 19 Ne to 37 K, are currently fully characterized. There are several ongoing efforts to determine the mixing ratios for medium-mass nuclei. Measuring transitions in lighter nuclei, such as 17 F, 15 O, 13 N and 11 C, poses new challenges as their longer half-lives, ranging from 1 to 22 min, conflict with the time constraints present at the large radioactive ion beam facilities where these nuclei are typically produced. We will present a proposed ion trapping experiment to measure these transitions at the University of Notre Dame where time constraints are less stringent. [ABSTRACT FROM AUTHOR]

Tests of the unitarity of the Cabbibo-Kobayashi-Masakawa (CKM) matrix offer an important avenue for constraining the Standard Model of the electroweak interaction. Several methods are currently used to determine Vud, the largest element in the top-row normalization test. One such method is through the study of superallowed T = 1/2 mixed mirror transitions, which offers a complementary method to the current most-precise value that is determined from superallowed pure Fermi 0+ → 0+ transitions. The precision currently achievable by this method is currently limited by the very low number of transitions for which the Fermi-to-Gamow-Teller mixing ratio ρ has been measured. St. Benedict, the Superallowed Transition Beta-Neutrino Decay-Ion-Coincidence Trap, is currently under development at the University of Notre Dame's Nuclear Science Laboratory, and intends to determine ρ for a range of new isotopes through measurements of the β-neutrino asymmetry parameter aβν using a linear Paul trap. In order to trap these ions, the fast, continuous secondary beam separated by the TwinSol twin solenoid separator must be thermalized and bunched. The system through which this will be done will feature a large-volume gas cell in which the ions will be thermalized, a double-RF-funnel-based ion guide system for the extraction of the ions, and a radiofrequency quadrupole (RFQ) to provide cooled ion bunches for capture in the Paul trap. [ABSTRACT FROM AUTHOR]

The low-energy beam and ion trap Penning trap mass spectrometer was used for an improved determination of the 48Ca double-β decay Q value: Qββ -- 4268.121 (79) keV. The new value is 1.2 keV greater than the value in the 2012 atomic mass evaluation [Chin. Phys. C 36, 1603 (2012)], a shift of three a, and is a factor of 5 more precise. Accurate knowledge of this Q value is important for experimental searches to observe neutrinoless double-β) decay (0vββ) in 48Ca and is essential for extracting the effective mass of the electron neutrino if the 48Ca half-life of Ovfifi was experimentally determined. [ABSTRACT FROM AUTHOR]

Abstract: We present a description of the Radio Frequency Quadrupole (RFQ) ion trap built as part of the TITAN facility. It consists of a gas-filled, segmented, linear Paul trap and is the first stage of the TITAN setup with the purpose of cooling and bunching radioactive ion beams delivered from ISAC-TRIUMF. This is the first such device to be driven digitally, i.e., using a high voltage (), wide bandwidth () square-wave as compared to the typical sinusoidal wave form. Results from the commissioning of the device as well as systematic studies with stable and radioactive ions are presented including efficiency measurements with stable 133Cs and radioactive 124,126Cs. A novel and unique mode of operation of this device is also demonstrated where the cooled ion bunches are extracted in reverse mode, i.e., in the same direction as previously injected. [Copyright &y& Elsevier]

The Beta-decay Paul Trap is an open-geometry, linear trap used to measure the decays of 8Li and 8B to search for a tensor contribution to the weak interaction. In the latest 8Li measurement of Burkey et al. (2022), β scattering was the dominant experimental systematic uncertainty. The Beta-decay Paul Trap Mk IV reduces the prevalence of β scattering by a factor of 4 through a redesigned electrode geometry and the use of glassy carbon and graphite as electrode materials. The trap has been constructed and successfully commissioned with 8Li in a new data campaign that collected 2.6 million triple coincidence events, an increase in statistics by 30% with 4 times less β scattering compared to the previous 8Li data set. [ABSTRACT FROM AUTHOR]

Abstract: We present a first direct Q-value measurement of the reaction using the TITAN mass-measurement facility at ISAC/TRIUMF. The measurements were performed in a Penning trap on neon-like 71Ga21+ and 71Ge22+ using isobar separation of the on-line produced mother and daughter nuclei through threshold charge breeding in an electron-beam ion trap. In addition, isoionic samples of 71Ga21+ and 71Ge21+ were stored concurrently in the Penning trap and provided a separate Q-value measurement. Both independent measurements result in a combined Q-value of , which is in agreement with the previously accepted Q-value for the ν cross-section calculations. Together with a recent measurement of the ν-response from the excited states in 71Ge, we conclude that there are no further uncertainties in the nuclear structure, which could remove the persistent discrepancy between the SAGE and GALLEX calibration measurements performed with neutrinos from reactor-produced 51Cr and 37Ar sources and the theoretical expectation. [Copyright &y& Elsevier]

The Superallowed Transition BEta NEutrino Decay Ion Coincidence Trap (St. Benedict) aims to conduct precision tests of the standard model by allowing for a determination of the Fermi to Gamow–Teller mixing ratio for many mirror transitions. St. Benedict will include a gas cell, a differentially-pumped extraction system, a radio-frequency (RF) cooler and buncher, and a Paul trap where the measurement will take place. The extraction system will include a first section housing a RF carpet at a pressure of around 3 mbar, followed by a second section housing a radio-frequency quadrupole (RFQ) ion guide at a pressure of 2 × 1 0 − 3 mbar. Transport efficiency of potassium ions using the RF carpet in static gas was determined to be above 90% using the ion surfing method after optimizing the potentials applied to various electrodes. [ABSTRACT FROM AUTHOR]

Abstract: TITAN (TRIUMF''s Ion Trap for Atomic and Nuclear science) is a system of multiple ion traps installed at the radioactive ion beam facility ISAC. The uniqueness of the system lies in the combination of different kinds of ion traps nowhere else available, and the coupling of this system to ISAC as a source of the most intense radioactive beams of very exotic nuclei worldwide. ISAC is now been operational for more than 5 years, and has been proven to be able to deliver a broad variety of radioactive species with unsurpassed production yields, making it the facility of choice for a next generation ion trap facility, like TITAN. The physics goals of TITAN are manifold, but the emphasis lies on the test of the Standard Model via the determination of the V ud CKM matrix element, nuclear structure and halo-nuclei investigations, and nuclear astrophysics by providing precise and accurate mass measurements. [Copyright &y& Elsevier]

The JYFLTRAP double Penning trap at the Ion Guide Isotope Separator On-Line facility has been used to measure the atomic masses of 13 neutron-rich rare-earth isotopes. Eight of the nuclides, 161Pm, 163Sm, 164,165Eu, 167Gd, and 165,167,168Tb, were measured for the first time. The systematics of the mass surface has been studied via one- and two-neutron separation energies as well as neutron pairing-gap and shell-gap energies. The proton-neutron pairing strength has also been investigated. The impact of the new mass values on the astrophysical rapid neutron capture process has been studied. The calculated abundance distribution results in a better agreement with the solar abundance pattern near the top of the rare-earth abundance peak at around A≈165. [ABSTRACT FROM AUTHOR]