Hyperfine Separation of Tritium

Abstract

The hyperfine separation of tritium has been measured with respect to the hyperfine separation of hydrogen by comparing the frequency of the tritium maser with that of a hydrogen maser. The result is A?(T) = 1 516 701 470.8087±0.0071 Hz, where it is assumed that Av (H) = 1 420 405 751.8 Hz. Wall shifts were measured for tritium and hydrogen for FEP Teflon at 35 °C. For a spherical bulb, d cm in diameter, the fractional wall shift for hydrogen is -(3.61±0.54) X lO" 10 /^ and for tritium it is -(3.14±0.47) X 10~1 0 /d.

A critical compilation of experimental data on spectral lines and energy levels of hydrogen, deuterium, and tritium

“…The measurements on hydrogen were critically analyzed by Karshenboim [14], who recommended the final value 1 420.405 751 768 MHz with a conservative estimate of uncertainty as ±1 mHz. The values actually measured by Mathur et al [16] and Wineland and Ramsey [15] were the ratios of the maser frequencies in tritium and deuterium to the one in hydrogen. Thus, adjustment of the value of the hydrogen maser frequency requires a corresponding adjustment of the tritium and deuterium values.…”

“…Such values should not be used if uncertainty smaller than ±20 kHz is required. The off-diagonal corrections to the 2P 1/2 and 2P 3/2 hfs splittings were calculated by Lundeen [90], Newton et al [95] and Lundeen and Pipkin [88] by diagonalizing the matrix resulting from formulas (10a) and (16) of Brodsky and Parsons [20]. These corrections result in a downward shift of the 2P 1/2,F=1 level by 2.5 kHz and an upward shift of the 2P 3/2,F=1 by the same amount.…”

“…Thus, adjustment of the value of the hydrogen maser frequency requires a corresponding adjustment of the tritium and deuterium values. Using this adopted value for the hydrogen maser frequency, we re-calculated the value for tritium from Mathur et al [16] to be 1 516.701 470 775 (7) MHz. It turns out that the adopted value for the hydrogen maser frequency coincides with the reference value used by Wineland and Ramsey [15] in their deuterium measurement, so their result for deuterium, 327.384 352 522 2(17) MHz, does not require any correction.…”

“…Their original result for hydrogen, 1 420.405 762(4) MHz [71], was greatly improved by Crampton et al [72], who obtained 1 420.405 751 800(28) MHz. The same team measured the ground-state hfs interval in deuterium [73] and tritium [16] masers. Their results were 327.384 352 30 (25) MHz for deuterium and 1 516.701 470 808 7(71) MHz for tritium.…”

“…For hydrogen, the frequency of the hfs maser has been measured to an extraordinary precision of seven parts in 10 13 [11][12][13][14] and is equal to 1 420 405 751.768(1) Hz [14]. For deuterium and tritium, the corresponding frequencies are 327 384 352.522 2(17) Hz [15] and 1 516 701 470.775 (7) Hz [16]. The theory of the hfs is not as well developed as the theory of the fine structure.…”