Precision Measurement of Orthopositronium Decay Rate Using SiO_2 Powder

Abstract

The intrinsic decay rate of orthopositronium formed in $\mathrm{Si}{\mathrm{O}}_2$ powder is measured using the direct $2\gamma$ correction method such that the time dependence of the pick-off annihilation rate is precisely determined using high energy-resolution germanium detectors. As a systematic test, two different types of $\mathrm{Si}{\mathrm{O}}_2$ powder are used with consistent findings. The intrinsic decay rate of orthopositronium is found to be $7.0396\pm 0.0012(stat.)\pm 0.0011(sys.)\mu s^{-1}$, which is consistent with previous measurements using $\mathrm{Si}{\mathrm{O}}_2$ powder with about twice the accuracy. Results agree well with a recent $O({\alpha }^2)$ QED prediction, varying $3.8-5.6$ experimental standard deviations from other measurements.

16 pages, 7 figures included. To be published in Physics Letters B

References in corpus (1)

• Search for an exotic three-body decay of orthopositronium

Cited by in corpus (20)

• Flavour physics of leptons and dipole moments
• Feasibility study of the positronium imaging with the J-PET tomograph
• Direct Observation of the Hyperfine Transition of the Ground State Positronium
• New Precision Measurement of Hyperfine Splitting of Positronium
• A feasibility study of ortho-positronium decays measurement with the J-PET scanner based on plastic scintillators
• First test of $O({\alpha }^2)$ correction of the orthopositronium decay rate
• Search for CP-violation in Positronium Decay
• First Millimeter-wave Spectroscopy of the Ground-state Positronium
• Positronium Portal into Hidden Sector: A new Experiment to Search for Mirror Dark Matter
• Positronium as a probe for new physics beyond the standard model
• Orthopositronium lifetime: analytic results in O(alpha) and O(alpha^3 ln(alpha))
• Positronium oscillations to Mirror World revisited
• Orthopositronium lifetime at O(alpha) and O(alpha^3 ln(alpha)) in closed form
• Theoretical study of the Compton effect with correlated three-photon emission: From the differential cross section to high-energy triple-photon entanglement
• Precise measurement of positronium hyperfine splitting using the Zeeman effect
• Reconciling the nonrelativistic QCD prediction and the $J/\psi \to 3\gamma$ data
• Positronium Decays with Dark $Z$ and Fermionic Dark Matter
• Irrational constants in positronium decays
• Feasibility study of the time reversal symmetry tests in decays of metastable positronium atoms with the J-PET detector
• A new approach for the ortho-positronium lifetime determination in a vacuum cavity