Lifetime measurements in ⁴¹Ar and ⁴¹K

The Doppler-shift attenuation method has been used in conjunction with a solid argon target and p-γ coincidences following the ⁴⁰Ar(d, p) reaction to determine the lifetimes or obtain lifetime limits for six levels in ⁴¹Ar. The lifetimes measured were as follows: 1035 keV level (6.5_-3.7⁺⁴⁰ ps); 1354 keV (0.46±0.12 ps); 2398 keV (0.17±0.05 ps); 2733 keV (< 0.045 ps); 2948 keV (< 0.09 ps) and 3010 keV (< 0.16 ps). In addition, singles γ-ray measurements with both solid and gas targets were made, and lifetimes or lifetime limits for a further two levels in ⁴¹Ar and nine in ⁴¹K were extracted. These results are discussed and compared to previous measurements.