High Precision Measurement of the $^{19}$Ne Lifetime

Abstract

<p>The lifetime of $^{19}$Ne is an important parameter in precision tests of the Standard Model. Improvement in the uncertainty of experimental observables of this and other $T=\frac{1}{2}$ mirror isotopes would allow for an extraction of</p><p>V$_{ud}$ at a similar precision to that obtained by superallowed $0^+\rightarrow0^+$ Fermi decays. We report on a new high precision measurement of the lifetime of $^{19}$Ne, performed at the Kernfysich Versneller Instituut (KVI) in Groningen, the Netherlands. A 10.5 $\frac{MeV}{A}$ $^{19}$F beam was used to produce $^{19}$Ne using inverse reaction kinematics in a H$_2$ gas target. Contaminant productions were eliminated using the TRI$\mu$P magnetic isotope separator. The $^{19}$Ne beam was implanted into a thick aluminum tape, which was translated to a shielded detection region by a custom tape drive system. Collinear annihilation radiation from the emitted decay positrons were detected by two high purity germanium (HPGe) detectors. Event pulse waveforms were digitized and stored using a CAEN V1724 Digitizer. Systematic studies were performed to characterize rate-dependent data acquisition effects, diffusion, backgrounds, and contamination from the separator. We have obtained the result for the lifetime of $\tau = 24.9344 \pm 0.0073(stat) \pm 0.0083(sys)$ seconds.</p>