Low-Background In-Trap Decay Spectroscopy with TITAN at TRIUMF

An in-trap decay spectroscopy setup has been developed and constructed for use with the TITAN facility at TRIUMF. The goal of this device is to observe weak electron-capture (EC) branching ratios for the odd-odd intermediate nuclei in the $\beta\beta$ decay process. This apparatus consists of an up-to 6 Tesla, open-access spectroscopy ion-trap, surrounded radially by up to 7 planar Si(Li) detectors which are separated from the trap by thin Be windows. This configuration provides a significant increase in sensitivity for the detection of low-energy photons by providing backing-free ion storage and eliminating charged-particle-induced backgrounds. An intense electron beam is also employed to increase the charge-states of the trapped ions, thus providing storage times on the order of minutes, allowing for decay-spectroscopy measurements. The technique of multiple ion-bunch stacking was also recently demonstrated, which further extends the measurement possibilities of this apparatus. The current status of the facility and initial results from a $^{116}$In measurement are presented.Comment: Proceedings for the 2nd International Conference on Advances in Radioactive Isotope Science (ARIS2014

Sensitivity Increases for the TITAN Decay Spectroscopy Program

The TITAN facility at TRIUMF has recently initiated a program of performing decay spectroscopy measurements in an electron-beam ion-trap (EBIT). The unique environment of the EBIT provides backingfree storage of the radioactive ions, while guiding charged decay particles from the trap centre via the strong magnetic field. This measurement technique is able to provide a significant increase in detection sensitivity for photons which result from radioactive decay. A brief overview of this device is presented, along with methods of improving the signal-to-background ratio for photon detection by reducing Compton scattered events, and eliminating vibrational noise

Sensitivity Increases for the TITAN Decay Spectroscopy Program

The TITAN facility at TRIUMF has recently initiated a program of performing decay spectroscopy measurements in an electron-beam ion-trap (EBIT). The unique environment of the EBIT provides backingfree storage of the radioactive ions, while guiding charged decay particles from the trap centre via the strong magnetic field. This measurement technique is able to provide a significant increase in detection sensitivity for photons which result from radioactive decay. A brief overview of this device is presented, along with methods of improving the signal-to-background ratio for photon detection by reducing Compton scattered events, and eliminating vibrational noise

The TITAN in-trap decay spectroscopy facility at TRIUMF

This paper presents an upgraded in-trap decay spectroscopy apparatus which has been developed and constructed for use with TRIUMF׳s Ion Trap for Atomic and Nuclear science (TITAN). This device consists of an open-access electron-beam ion-trap (EBIT), which is surrounded radially by seven low-energy planar Si(Li) detectors. The environment of the EBIT allows for the detection of low-energy photons by providing backing-free storage of the radioactive ions, while guiding charged decay particles away from the trap centre via the strong (up to 6 T) magnetic field. In addition to excellent ion confinement and storage, the EBIT also provides a venue for performing decay spectroscopy on highly charged radioactive ions. Recent technical advancements have been able to provide a significant increase in sensitivity for low-energy photon detection, towards the goal of measuring weak electron-capture branching ratios of the intermediate nuclei in the two-neutrino double beta (2νββ2νββ) decay process. The design, development, and commissioning of this apparatus are presented together with the main physics objectives. The future of the device and experimental technique are discussed

Precision mass measurements of short-lived nuclides for nuclear structure studies at TITAN

TITAN (TRIUMF’s Ion Trap for Atomic and Nuclear science) at TRIUMF’s rare isotope beam facility ISAC is an advanced Penning trap based mass spectrometer dedicated to precise and accurate mass determinations. An overview of TITAN, the measurement technique and a highlight of recent mass measurements of the short-lived nuclides important to the nuclear structure program at TITAN are presented

Mass measurements of neutron-rich Rb and Sr isotopes

We report on the mass measurements of several neutron-rich Rb and Sr isotopes in the A≈100 region with the TITAN Penning-trap mass spectrometer. By using highly charged ions in the charge state q=10+, the masses of 98,99Rb and 98-100 Sr have been determined with a precision of 6–12 keV, making their uncertainty negligible for r-process nucleosynthesis network calculations. The mass of 101 Sr has been determined directly for the first time with a precision eight times higher than the previous indirect measurement and a deviation of 3σ when compared to the Atomic Mass Evaluation. We also confirm the mass of 100 Rb from a previous measurement. Furthermore, our data indicate the existence of a low-lying isomer with 80keV excitation energy in 98 Rb. We show that our updated mass values lead to minor changes in the r process by calculating fractional abundances in the A≈100 region of the nuclear chart

In-Trap Spectroscopy of Charge-Bred Radioactive Ions

In this Letter, we introduce the concept of in-trap nuclear decay spectroscopy of highly charged radioactive ions and describe its successful application as a novel spectroscopic tool. This is demonstrated by a measurement of the decay properties of radioactive mass A=124 ions (here, 124In and 124Cs) in the electron-beam ion trap of the TITAN facility at TRIUMF. By subjecting the trapped ions to an intense electron beam, the ions are charge bred to high charge states (i.e., equivalent to the removal of N-shell electrons), and an increase of storage times to the level of minutes without significant ion losses is achieved. The present technique opens the venue for precision spectroscopy of low branching ratios and is being developed in the context of measuring electron-capture branching ratios needed for determining the nuclear ground-state properties of the intermediate odd-odd nuclei in double-beta (ββ) decay