Charmonium spectroscopy from radiative decays of the J/psi and psi'

Thesis/Dissertation · Fri Dec 31 23:00:00 EST 1982

OSTI ID:5211117

Gaiser, J E

Data were collected at the Stanford Linear Accelerator Center's electron-positron colliding beam machine, SPEAR, intermittently over a two and half year period, beginning at the end of 1978. This detector is excellently suited for studying the radiative transitions among the charmonium family of states: from PSIPRIME(3684) to the triplet P states, CHI(3415), CHI(3510), and CHI(3550); from PSIPRIME(3684) and J/PSI(3095) to the singlet S state ETAc(2984); and from PSIPRIME(3684) to the radially excited singlet S state ETAc'(3592). The analysis of 1,800,000 PSIPRIME(3684) and 2,200,000 J/PSI(3095) decays yields the following spectrum of states: CHIO(3418), CHI1(3512), CHI2(3558), ETAc(2984), and ETAc'(3592), each with a +/-4 MeV error on its mass. The branching ratios are measured to be: B(PSIPRIME(3684) ..-->.. ..gamma.. + CHIJ) = (9.9 +/- 0.5 +/- 0.8)%, (9.0 +/- 0.5 +/- 0.7)%, and (8.0 +/- 0.5 +/- 0.7)%, for J = 0, 1, 2, respectively; B(PSIPRIME(3684) ..-->.. ..gamma.. + ETAc) = (0.28 +/- 0.06)% and B(J/PSI(3095) ..-->.. ..gamma.. + ETAc) = (1.27 +/- 0.36)%; and B(PSIPRIME(3684) ..-->.. ..gamma.. + ETAc') = (0.5-1.2)% at the 90% confidence level. Values for the natural line widths are obtained: Width(CHIJ) = (13.5-20.4) MeV, <3.8 MeV, (0.85-4.9) MeV, for J = 0, 1, 2, respectively (90% C.L.); Width (ETAc) = (11.5 + 4.5/-4.0) MeV; and Width(ETAc') <7 MeV (90% C.L.). The cascade product branching ratios B(PSIPRIME(3684) ..-->.. ..gamma.. +/- CHIJ) times B(CHIJ ..-->.. ..gamma.. + J/PSI(3095)) were measured for J = 1 and 2 to be: (2.56 +/- 0.12 +/- 0.20)% and (0.99 +/- 0.10 +/- 0.08)%, respectively. No signal was seen for the J = 0 transition, with an upper limit above its previously measured product branching ratio. The results of this analysis are compared with the predictions of the charmonium models.

• Research Organization: Stanford Univ., CA (USA)
• OSTI ID: 5211117
• Country of Publication: United States
• Language: English

Related Subjects

645101* -- High Energy Physics-- Particle Interactions &amp; Properties-Experimental-- Electromagnetic Interactions &amp; Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BOSONS
BRANCHING RATIO
CHARMONIUM
CHI RESONANCES
CHI-3455 RESONANCES
CHI-3500 RESONANCES
CHI-3550 RESONANCES
DATA
ELECTRON-POSITRON INTERACTIONS
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
HADRONS
INFORMATION
INTERACTIONS
LEPTON-LEPTON INTERACTIONS
MASSLESS PARTICLES
MESON RESONANCES
MESONS
NUMERICAL DATA
PARTICLE INTERACTIONS
PARTICLE PROPERTIES
PARTICLE WIDTHS
PHOTONS
PSI RESONANCES
PSI-3105 RESONANCES
PSI-3695 RESONANCES
QUARKONIUM
RADIATIVE DECAY
RESONANCE PARTICLES
SPEAR
STORAGE RINGS
VECTOR MESONS