Search for the Theta+ -> p K0S pentaquark in CDF Run II data
Following reports over the last year of evidence for exotic baryons
containing 5 quarks (pentaquarks), we analyze CDF Run II data for evidence
of the Theta+ pentaquark (u u d d s-bar) with a mass of about 1.54 GeV
decaying into a proton and a K0S.
Both low-pT data from the zerobias and minimum bias triggers, and
high-pT data from the jet20 trigger are analyzed.
Protons are identified with the time-of-flight detector.
To investigate the sensitivity of CDF for this type of search,
known resonances are reconstructed in the following modes:
phi -> K+K-, K*0 -> K+pi-, Lambda(1520) -> pK- and K*+ ->pi+K0S.
We find no evidence for a narrow resonance in the pK0S channel
in either dataset.
Description
A description of the analysis is available here.
Figures
Below the eps versions of all figures available for downloads.
If space limitations do not allow to show plots from both datasamples,
we recommend the minbias plots.
-
K0S mass peaks.
minbias:
eps
gif
jet20:
eps
gif
-
TOF separation plots.
minbias:
eps
gif
jet20:
eps
gif
-
m(KK) mass spectrum with phi peak:
minbias:
eps
gif
jet20:
eps
gif
-
m(Kp) mass spectrum with Lambda(1520) peak:
minbias:
eps
gif
jet20:
eps
gif
-
m(piK) mass spectrum with K*0(892) peak:
minbias:
eps
gif
jet20:
eps
gif
-
m(piKs) mass spectrum with K*+(892) peak:
minbias:
eps
gif
jet20:
eps
gif
-
invariant mass resolution vs Q-value:
minbias:
eps
gif
-
m(pKs) mass spectrum:
minbias:
eps
gif
jet20:
eps
gif
-
Background subtracted zoom of m(pKs) mass spectrum:
minbias:
eps
gif
jet20:
eps
gif
-
m(pKs) mass spectrum (protons only):
minbias:
eps
gif
jet20:
eps
gif
-
m(pKs) mass spectrum (antiprotons only):
minbias:
eps
gif
jet20:
eps
gif
For CDF collaborators only
A more detailed description of the analysis is available in
CDFnote 6975
The pre-blessing talk
at the April 15, 2004 B Physics meeting, and the April 28, 2004
blessing talk
offer a summary of the analysis.
