Measurement of Central Exclusive Hadron Pair Production in CDF

M. Albrow1, J. Lewis1, M. Żurek2,3, D. Lontkovskyi4, I. Makarenko4, J.S. Wilson5
1Fermilab, 2University of Cologne, 3Research Center Juelich, 4University of Kyiv, 5University of Michigan
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We present a study in CDF of \(p\bar{p}\) collisions at the Tevatron that have 2 charged hadrons in the central region, \(|\eta| < 1.3\) with large rapidity gaps (no hadrons) on either side. The reaction is \(p + \bar{p} \rightarrow p + X + \bar{p}\), where the "+" stands for a rapidity gap \(G\); we use the notation \(GXG\). Here we present a study of events with exactly two charged hadron tracks in the central detector, which we show to be often the result of the decay of a single neutral resonance, such as \(f_0^0\) or \(f_2^0\) states, or (rarely) the \(\chi_c\). These events are expected to be dominated by double pomeron, \(\pom\), exchange in the \(t\)-channel; hence \(\pom + \pom\rightarrow X\). Only specific quantum numbers for \(X\) are allowed. Additionally, we see a signal for photoproduction of the \(J/ψ\) stats, which provides a check of our mass scale, resolution, and cross section calculation. We also place limits on exclusive production of \(\chi_c\) production and decay in the \(π^+π^-\) and \(K^+K^-\) channels.

We use data taken at \(\sqrt{s}\) = 1960 GeV and 900 GeV. This data provides a useful window on hadron spectroscopy, as well as providing benchmarks for testing pomeron models.

More information is available in CDF public note 11034.