A Search for the singlet-P state h_c(1¹ P₁) of charmonium in proton-antiproton annihilations at Fermilab experiment E835p

Thesis/Dissertation · Wed Dec 01 00:00:00 EST 2004

DOI:https://doi.org/10.2172/879172· OSTI ID:879172

Joffe, David Noah ^[1]

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1. Northwestern Univ., Evanston, IL (United States)

The author presents the results of a search for the spin-singlet P-wave state h_c(1¹ P₁) of charmonium formed through proton-antiproton annihilation at Fermilab experiment E835. The decay channels which were studied were p$$\bar{p}$$ → J/Ψ + X → e⁺e^- + X, p$$\bar{p}$$ → J/Ψ + π⁰ → e⁺e^- + γγ, p$$\bar{p}$$ → J/Ψ + π⁰π⁰ → e⁺e^- + 4γ, and the neutral channel p$$\bar{p}$$ → η_cγ → (γγ)γ. The decay p$$\bar{p}$$ → J/Ψγ → e⁺e^-γ, into which ¹P₁ decay is forbidden by C-parity conservation, was also examined for comparison. The 90% confidence upper limits for the decay channels studied in the mass range 3525.1-3527.3 MeV for a ¹P₁ resonance with a presumed width of 1.0 MeV were determined to be B(p$$\bar{p}$$ → ¹P₁) x B(¹P₁ → J/Ψ + X) ≤ 1.8 x 10^-7, B(p$$\bar{p}$$ → ¹P₁) x B(¹P₁ → J/Ψ + π⁰) ≤ 1.2 x 10^-7, and B(p$$\bar{p}$$ → ¹P₁) x B(¹P₁ → J/Ψγ) ≤ 1.0 x 10^-7. No evidence for a ¹P₁ enhancement was observed in either of the two additional reactions studied; p$$\bar{p}$$ → J/Ψ + π⁰π⁰ → e⁺e^- + 4γ and p$$\bar{p}$$ → η_cγ → (γγ)γ.

• Research Organization: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 879172
• Report Number(s): FERMILAB-THESIS-2004-57; arXiv eprint number hep-ex/0505007; TRN: US0605123
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANNIHILATION
CHARMONIUM
DECAY
FERMILAB
RESONANCE
Experiment-HEP