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Abstract: A new procedure to prepare isomerically clean samples of short-lived ions with a mass resolving power of more than 1×105 has been developed at the JYFLTRAP tandem Penning trap system. The method utilises a dipolar rf-excitation of the ion motion with separated oscillatory fields in the precision trap. During a subsequent retransfer to the purification trap, the contaminants are rejected and as a consequence, the remaining bunch is isomerically cleaned. This newly-developed method is suitable for very high-resolution cleaning and is at least a factor of five faster than the methods used so far in Penning trap mass spectrometry. [Copyright &y& Elsevier]

Abstract: A carbon-cluster ion source based on laser ablation and ionization of a carbon sample has been built and tested for the JYFLTRAP setup. In the present configuration the ion source is situated in the electrostatic switchyard in front of the radiofrequency (RFQ) cooler and buncher. In this position the beam quality of the carbon clusters injected into the Penning trap system is considerably improved by the RFQ. Moreover, the mass-dependence of the RFQ’s transmission can be used to some extent to suppress unwanted cluster sizes. [Copyright &y& Elsevier]

Abstract: Masses of the radioactive isotopes 62Ga, 62Zn and 62Cu have been measured at the JYFLTRAP facility with a relative precision of better than . A value of () keV for the superallowed decay of 62Ga is obtained from the measured cyclotron frequency ratios of 62Ga 62Zn, 62Ga 62Ni and 62Zn 62Ni ions. The resulting -value supports the validity of the conserved vector current hypothesis (CVC). The mass excess values measured were () keV for 62Ga, () keV for 62Zn and () keV for 62Cu. [Copyright &y& Elsevier]

Abstract: Cooling and trapping techniques of low-energy radioactive ion beams of refractory elements employed at the IGISOL facility are presented with emphasis on high-precision measurements of the ground state properties of exotic nuclei. The impact of the new generation Paul and Penning traps on mass measurements of short-lived nuclei is discussed with examples on precision measurements of masses of super-allowed beta emitters and neutron-rich nuclei. As a new concept the trap-assisted spectroscopy of radioactive ions is presented with applications in collinear laser spectroscopy, decay spectroscopy of isobarically purified sources and in nuclear cross-section measurements by ion counting. [Copyright &y& Elsevier]

Abstract: The JYFLTRAP setup has been used for precision mass spectrometry since 2003. An essential part of this setup is the computer-controlled system consisting of software and hardware that is required to operate the instruments. The software has been developed solely at JYFL using LabVIEW and C++ development tools. The hardware consists of devices controlled using Control Area Network (CAN) field bus and Ethernet for communication purposes. LAN/GPIB-gateways, modular multichannel ISEG DC power supplies and WAGO I/O systems are also used. [Copyright &y& Elsevier]

Abstract: The field stability of a mass spectrometer plays a crucial role in the accuracy of mass measurements. In the case of mass determination of short-lived nuclides with a Penning trap, major causes of fluctuations are temperature variations in the vicinity of the trap and pressure changes in the liquid helium cryostat of the superconducting magnet. Thus systems for the temperature and pressure stabilization of the Penning trap mass spectrometer ISOLTRAP at the ISOLDE facility at CERN have been installed. A reduction of the temperature and pressure fluctuations by at least an order of magnitude down to and has been achieved, which corresponds to a relative magnetic field change of and , respectively. [Copyright &y& Elsevier]

Abstract: Multiply charged ions of stable xenon isotopes from a plasma ion source have been mass-selected by the on-line mass separator ISOLDE/CERN and delivered to the triple-trap mass spectrometer ISOLTRAP. The doubly charged ions that survived the charge-exchange processes during bunching and ion preparation were transferred to a precision Penning trap for mass determination. Mass values were obtained for the isotopes with mass numbers . They are consistent with previous results except for the case of where a significant deviation from the literature value was found. The performance of ISOLTRAP is analyzed with respect to a future application of highly charged ions for mass determination of short-lived radionuclides at ISOLDE. [Copyright &y& Elsevier]

A Penning trap has been installed for isobaric beam purification at the IGISOL-facility at the University of Jyväskylä. In this paper, the technical details of this new device together with results of the first tests are presented. The mass resolving power, depending on the excitation parameters and the ion species, can be as high as 145 000 and the total transmission has been determined to be 17%. In addition, it is shown that with this experimental setup it is possible to measure atomic masses up to A=120 with accuracies of approximately 50 keV. [Copyright &y& Elsevier]