Measurement of the Branching Ratio of $\pi^0$ Dalitz Decay using $K_L \rightarrow \pi^0\pi^0\pi^0$ Decays

Abouzaid, E.; Arenton, M.; Barker, A. R.; Bellantoni, L.; Blucher, E.; Bock, G. J.; Cheu, E.; Coleman, R.; Corcoran, M. D.; Cox, B.; Erwin, A. R.; Escobar, C. O.; Glazov, A.; Golossanov, A.; Gomes, R. A.; Gouffon, P.; Hsiung, Y. B.; Jensen, D. A.; Kessler, R.; Kotera, K.; Ledovskoy, A.; McBride, P. L.; Monnier, E.; Nguyen, H.; Niclasen, R.; Phillips, D. G.; Ramberg, E. J.; Ray, R. E.; Ronquest, M.; Santos, E.; Slater, W.; Smith, D.; Solomey, N.; Swallow, E. C.; Toale, P. A.; Tschirhart, R.; Wah, Y. W.; Wang, J.; White, H. B.; Whitmore, J.; Wilking, M. J.; Winstein, B.; Winston, R.; Worcester, E. T.; Yamanaka, T.; Zimmerman, E. D.; Zukanovich, R. F.

doi:10.1103/PhysRevD.100.032003

Title: Measurement of the Branching Ratio of $$\pi^0$$ Dalitz Decay using $$K_L \rightarrow \pi^0\pi^0\pi^0$$ Decays

Journal Article · Mon Aug 05 00:00:00 EDT 2019 · Physical Review. D.

DOI:https://doi.org/10.1103/PhysRevD.100.032003· OSTI ID:1547955

Abouzaid, E.; Arenton, M.; Barker, A. R.; Bellantoni, L.; Blucher, E.; Bock, G. J.; Cheu, E.; Coleman, R.; Corcoran, M. D.; Cox, B.; Erwin, A. R.; Escobar, C. O.; Glazov, A.; Golossanov, A.; Gomes, R. A.; Gouffon, P.; Hsiung, Y. B.; Jensen, D. A.; Kessler, R.; Kotera, K. more »

We present a measurement of B(π0→e+e-γ)/B(π0→γγ), the Dalitz branching ratio, using data taken in 1999 by the E832 KTeV experiment at Fermi National Accelerator Laboratory. We use neutral pions from fully reconstructed KL decays in flight; the measurement is based on ~60 thousand KL→π0π0π0→γγγγe+e-γ decays. We normalize to KL→π0π0π0→6γ decays. We find B(π0→e+e-γ)/B(π0→γγ) (me+e->15 MeV/c2)=[3.920±0.016(stat)±0.036(syst)]×10-3. Using the Mikaelian and Smith prediction for the e+e- mass spectrum, we correct the result to the full e+e- mass range. The corrected result is B(π0→e+e-γ)/B(π0→γγ)=[1.1559±0.0047(stat)±0.0106(syst)]%. This result is consistent with previous measurements, and the uncertainty is a factor of 3 smaller than any previous measurement.

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Research Organization:: Brookhaven National Laboratory (BNL), Upton, NY (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Univ. of Colorado, Boulder, CO (United States)

Sponsoring Organization:: USDOE Office of Science (SC), High Energy Physics (HEP)

Contributing Organization:: KTeV Experiment

Grant/Contract Number:: AC02-07CH11359; SC0010005; SC0012704

OSTI ID:: 1547955

Alternate ID(s):: OSTI ID: 1546039; OSTI ID: 1556988; OSTI ID: 1762107

Report Number(s):: BNL-211906-2019-JAAM; arXiv:1902.01375; FERMILAB-PUB-19-049-PPD; PRVDAQ; 032003

Journal Information:: Physical Review. D., Journal Name: Physical Review. D. Vol. 100 Journal Issue: 3; ISSN 2470-0010

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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