A study of. iota. (. eta. (1440)) and E (f sub 1 (1420)) production in two-photon reaction

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5261731

Wang, Yaoxun

A study of {iota} ({eta}(1,440)) production in untagged and E (f{sub 1}(1,420)) production in single-tagged two-photon reactions was performed at PEP with colliding e{sup +}e{sup {minus}} beam energies of 14.5 GeV. By observing the reaction {gamma}{gamma} {yields} K{sub s}{sup 0}K{sup {plus minus}}{pi}{sup {minus plus}}, a 95% confidence level limit of {Gamma}{sub {iota}{yields}{gamma}{gamma}}B ({iota} {yields} K{bar K}{pi}) < 1.6 keV for the {iota} meson has been obtained. If the {iota} decays predominantly into K{bar K}{pi}, the resulting {Gamma}{sub {iota}{yields}{gamma}{gamma}} limit appears to conflict with previous assignments of an observed {rho}{gamma} decay to {iota} and also with many analyses of {eta}-{eta}{prime}-{iota} mixing. The contrast of this small {gamma}{gamma} width with the large rate for J/{psi} {yields} {gamma}{iota} provides evidence that {iota} is a glueball with little admixture of q{bar q} states. The observation of the E meson is the first observation of a spin-1 state in two-photon collisions. The final state of the E was identified by detecting K{sup s}{sup 0}K{sup {plus minus}}{pi}{sup {minus plus}} in single-tagged production where one of the photons was quite virtual. The measured mass of the E meson is 1426{sub {minus}7}{sup +11} MeV, the total width is 16{sub {minus}15}{sup +25} MeV, and the E mainly decays through a K{sup {asterisk}}K intermediate state. Production of a spin-1 meson, which cannot be made by two real photons, would fit the observation of the E. The Q{sup 2} dependence of the data in the E mass region agrees with a spin-1 assignment and is incompatible with a spin-O hypothesis. The distributions in energies and angles of the decay particles of E favor positive parity.

• Research Organization: Cambridge City Hospital, MA (United States)
• OSTI ID: 5261731
• Country of Publication: United States
• Language: English

Related Subjects

662310* -- Weak &amp; Electromagnetic Interactions of Leptons-- (1992-)
662390 -- Electromagnetic Processes &amp; Properties-- (1992-)
662420 -- Properties of Mesons &amp; Meson Resonances-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AXIAL VECTOR MESONS
BASIC INTERACTIONS
BOSONS
DECAY
ELECTROMAGNETIC INTERACTIONS
ELECTRON-POSITRON INTERACTIONS
ELEMENTARY PARTICLES
ETA-1440 MESONS
F1-1420 MESONS
FINAL-STATE INTERACTIONS
GLUEBALLS
HADRONS
INTERACTIONS
KAONS
LEPTON-LEPTON INTERACTIONS
LIMITING VALUES
MASS
MASS FORMULAE
MESONS
OKUBO MASS FORMULA
PARTICLE DECAY
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
PARTICLE PROPERTIES
PARTICLE WIDTHS
PEP STORAGE RINGS
PHOTON-PHOTON INTERACTIONS
PIONS
PSEUDOSCALAR MESONS
STORAGE RINGS
STRANGE MESONS
STRANGE PARTICLES