We present results of a search for anomalous production of
events containing a charged lepton (l, either e or mu) and a photon
(gamma), both with high transverse momentum, accompanied by additional
signatures, X, including transverse energy (missing E(t)) and additional
leptons and photons. We use the same kinematic selection criteria as in
a previous CDF search, but with a substantially larger data set, 305 pb-1,
a p anti-p collision energy of 1.96 TeV, and the upgraded CDF II detector.
We find 42 l gamma missing E(t) events versus a standard model expectation
of 37.3 +/- 5.4 events. The level of excess observed in run I, 16 events
with an expectation of 7.6 +/- 0.7 events (corresponding to a 2.7 sigma
effect), is not supported by the new data. In the signature of ll gamma
+ X we observe 31 events versus an expectation of 23.0 +/- 2.7 events.
In this sample we find no events with an extra photon or missing E(t)
and so find no events like the one ee gamma gamma missing E(t) event
observed in Run I.
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Updated: Wednesday, 2008 November 19 13:58:15 CST automatically from input from carol picciolo