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Skwarnicki, T.

Publications and source records attributed to Skwarnicki, T..

14 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2016

Issues and opportunities in exotic hadrons

The last few years have been witness to a proliferation of new results concerning heavy exotic hadrons. Experimentally, many new signals have been discovered that could be pointing towards the existence of tetraquarks, pentaquarks, and other exotic configurations of quarks and gluons. Theoretically, advances in lattice field theory techniques place us at the cusp of understanding complex coupled-channel phenomena, modelling grows more sophisticated, and effective field theories are being applied to an ever greater range of situations. Consequently, it is thus an opportune time to evaluate the status of the field. In the following, a series of high priority experimental and theoretical issues concerning heavy exotic hadrons is presented.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Amplitude analyses of the decays χ c1 →ηπ⁺π⁻ and χ c1 →η'π⁺π⁻

Using a data sample of 2.59×10⁷ ψ(2S) decays obtained with the CLEO-c detector, we perform amplitude analyses of the complementary decay chains ψ(2S)→γχ c1 ; χ c1 →ηπ⁺π⁻ and ψ(2S)→γχ c1 ; χ c1 →η'π⁺π⁻. We find evidence for an exotic P-wave η'π amplitude, which, if interpreted as a resonance, would have parameters consistent with the π₁(1600) state reported in other production mechanisms. We also make the first observation of the decay a₀(980)→η'π and measure the ratio of branching fractions B(a₀(980)→η'π)/B(a₀(980)→ηπ)=0.064±0.014±0.014. The ππ spectrum produced with a recoiling η is compared to that with η' recoil.

Adams, G. S.↗
DOE OSTI2011

Studies of D⁺→{η',η,Φ}e⁺ν e

We report the first observation of the decay D⁺→η'e⁺ν e in two analyses, which combined provide a branching fraction of B(D⁺→η'e⁺ν e )=(2.16±0.53±0.07)×10⁻⁴. We also provide an improved measurement of B(D⁺→ηe⁺ν e )=(11.4±0.9±0.4)×10⁻⁴, provide the first form factor measurement, and set the improved upper limit B(D⁺→Φe⁺ν e )<0.9×10⁻⁴ (90%C.L.).

Yelton, J.↗