George M C, Lombardi L D, Hessels E A
Department of Physics, York University, 4700 Keele Street, Toronto, Ontario, Canada M3J 1P3.
Phys Rev Lett. 2001 Oct 22;87(17):173002. doi: 10.1103/PhysRevLett.87.173002. Epub 2001 Oct 5.
The 2(3)P(1)-to- 2(3)P(0) interval in atomic helium is measured using a thermal beam of metastable helium atoms excited to the 2(3)P state using a 1.08-microm diode laser. The 2(3)P(1)-to- 2(3)P(0) transition is driven by 29.6-GHz microwaves in a rectangular waveguide cavity. Our result of 29,616,950.9+/-0.9 kHz is the most precise measurement of helium 2(3)P fine structure. When compared to precise theory for this interval, this measurement leads to a determination of the fine-structure constant of 1/137.0359864(31).
利用1.08微米二极管激光器将亚稳态氦原子热束激发到2(3)P态，测量了原子氦中2(3)P(1)到2(3)P(0)的间隔。2(3)P(1)到2(3)P(0)的跃迁由矩形波导腔中的29.6吉赫兹微波驱动。我们得到的29,616,950.9±0.9千赫兹的结果是对氦2(3)P精细结构最精确的测量。与该间隔的精确理论相比，这一测量结果得出精细结构常数为1/137.0359864(31)。
