title: Precision measurement of the 6He half-life and the weak axial current in nuclei.
abstract: Studies of 6He beta decay along with tritium can play an important role in testing ab initio nuclear wave-function calculations and may allow for fixing low-energy constants in effective-field theories. Here, we present an improved determination of the 6He half-life to a relative precision of 3×10(-4). Our value of 806.89±0.11(stat)(-0.19syst)(+0.23)  ms resolves a major discrepancy between previous measurements. Calculating the statistical rate function we determined the ft value to be 803.04(-0.23)(+0.26)  s. The extracted Gamow-Teller matrix element agrees within a few percent with ab initio calculations.
authors.affiliation: Department of Physics and Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98195, USA. knechta@uw.edu
authors.forename: A
authors.initials: A
authors.lastname: Knecht
authors.forename: R
authors.initials: R
authors.lastname: Hong
authors.forename: D W
authors.initials: DW
authors.lastname: Zumwalt
authors.forename: B G
authors.initials: BG
authors.lastname: Delbridge
authors.forename: A
authors.initials: A
authors.lastname: García
authors.forename: P
authors.initials: P
authors.lastname: Müller
authors.forename: H E
authors.initials: HE
authors.lastname: Swanson
authors.forename: I S
authors.initials: IS
authors.lastname: Towner
authors.forename: S
authors.initials: S
authors.lastname: Utsuno
authors.forename: W
authors.initials: W
authors.lastname: Williams
authors.forename: C
authors.initials: C
authors.lastname: Wrede